Inger Sandlie

• Aaen, Kristin Hovden; Testa, Maria Francesca; Nilsen, Jeannette; Tarantino, Rebecca; Canepari, Cesare & Benedusi, Mascia [Vis alle 16 forfattere av denne artikkelen] (2025). Tailored collagen binding of albumin-fused hyperactive coagulation factor IX dictates in vivo distribution and functional properties. Nature Communications. 16. doi: 10.1038/s41467-025-62955-9. Fulltekst i vitenarkiv Vis sammendrag

  The efficacy of hemophilia B (HB) replacement therapy is evaluated by coagulation factor IX (FIX) activity in plasma, although FIX bound to extravascular type IV collagen (Col4) also contributes to efficient hemostasis. Here, we investigated the impact of engineering FIX for improved (K5R) or reduced (K5A) Col4 binding on the pharmacokinetic properties of FIX Padua, fused to human serum albumin (HSA QMP ) engineered for favorable neonatal Fc receptor (FcRn) engagement. Hyperactive features and extended plasma half-life in human FcRn expressing mice, attributed to FIX Padua and HSA QMP engineering, respectively, was confirmed. In HB mice, Padua KA -HSA QMP exhibited negligible extravascular distribution and the highest plasma levels at early time points followed by the steepest decay. Conversely, Padua KR -HSA QMP showed increased extravascular distribution and a 3-fold longer functional half-life (80 hours). These findings support the use of Padua KA -HSA QMP and Padua KR -HSA QMP as hyperactive short- or long-term therapeutics, respectively, with opportunities for tailored HB replacement therapy.

• Anthi, Aina Karen; Kolderup, Heidi Anette; Vaage, Eline Benno; Bern, Malin C.; Benjakul, Sopisa & Tjärnhage, Elias [Vis alle 32 forfattere av denne artikkelen] (2025). An intranasal subunit vaccine induces protective systemic and mucosal antibody immunity against respiratory viruses in mouse models. Nature Communications. 16(1), s. 1–16. doi: 10.1038/s41467-025-59353-6. Fulltekst i vitenarkiv Vis sammendrag

  Although vaccines are usually given intramuscularly, the intranasal delivery route may lead to better mucosal protection and limit the spread of respiratory virus while easing administration and improving vaccine acceptance. The challenge, however, is to achieve delivery across the selective epithelial cell barrier. Here we report on a subunit vaccine platform, in which the antigen is genetically fused to albumin to facilitate FcRn-mediated transport across the mucosal barrier in the presence of adjuvant. Intranasal delivery in conventional and transgenic mouse models induces both systemic and mucosal antigen-specific antibody responses that protect against challenge with SARS-CoV-2 or influenza A. When benchmarked against an intramuscularly administered mRNA vaccine or an intranasally administered antigen fused to an alternative carrier of similar size, only the albumin-based intranasal vaccine yields robust mucosal IgA antibody responses. Our results thus suggest that this needle-free, albumin-based vaccine platform may be suited for vaccination against respiratory pathogens.

• Nilsen, Jeannette; Aaen, Kristin Hovden; Benjakul, Sopisa; Ruso-Julve, Fulgencio; Greiner, Thomas Uwe & Bejan, Daniela [Vis alle 11 forfattere av denne artikkelen] (2025). Enhanced plasma half-life and efficacy of engineered human albumin-fused GLP-1 despite enzymatic cleavage of its C-terminal end. Communications Biology. 8(1). doi: 10.1038/s42003-025-08249-8. Fulltekst i vitenarkiv Vis sammendrag

  Albumin has a long plasma half-life due to engagement of the neonatal Fc receptor (FcRn), which prevents intracellular degradation. However, its C-terminal end can be cleaved by carboxypeptidase A, and removal of the last leucine residue (L585) weakens receptor binding, reducing its half-life from 20 days to 3.5 days in humans. This biology has so far been overlooked when designing human albumin-fused biologics. Thus, there is a need for an engineering strategy to secure favorable FcRn binding and pharmacokinetic properties. Here, we show that a branched aliphatic amino acid or methionine at position 585 of albumin is required for optimal receptor binding, which cannot be replaced to prevent enzymatic cleavage without negatively affecting FcRn engagement. As a solution, we report that C-terminally cleaved albumin can be efficiently rescued from intracellular degradation by introducing amino acid substitutions that improve FcRn binding. This albumin-engineering strategy was also effective when applied with a therapeutic fusion partner, glucagon-like peptide 1 (GLP-1), resulting in a 2-fold increase in plasma half-life and prolonged efficacy in human FcRn transgenic mice. We demonstrate how human albumin fusions should be tailored to ensure a long plasma half-life and enhanced efficacy of fused biologics, despite potential C-terminal cleavage in vivo.

• gjølberg, torleif; mester, simone; Calamera, Gaia; Telstad, Jenny Skjermo; Sandlie, Inger & Andersen, Jan Terje (2025). Targeting the Neonatal Fc Receptor in Autoimmune Diseases: Pipeline and Progress. BioDrugs. ISSN 1173-8804. 39(3), s. 373–409. doi: 10.1007/s40259-025-00708-2. Fulltekst i vitenarkiv Vis sammendrag

  Autoimmune diseases are highly prevalent and affect people at all ages, women more often than men. The most prominent immunological manifestation is the production of antibodies directed against self-antigens. In many cases, these antibodies (Abs) drive the pathogenesis by attacking the body’s own healthy cells, causing serious health problems that may be life threatening. Most autoantibodies are of the immunoglobulin G (IgG) isotype, which has a long plasma half-life and potent effector functions. Thus, there is a need for specific treatment options that rapidly eliminate these pathogenic IgG auto-Abs. In this review, we discuss how the neonatal Fc receptor (FcRn) acts as a regulator of the high levels of not only IgG Abs, but also albumin, by rescuing both these soluble proteins from cellular catabolism, and how a molecular and cellular understanding of this complex biology has spurred an intense interest in the development of FcRn-targeting strategies for the treatment of IgG-driven autoimmune diseases. We find that this emerging therapeutic class demonstrates efficacy within several autoimmune diseases with distinct pathophysiology. This offers hope for both new therapeutic avenues for highly prevalent diseases currently treated by other means, and rare diseases with no approved therapies to date. In addition, we elaborate on studies that have led to approval of the first FcRn antagonists, the clinical progress and structural design of molecules in the pipeline, their position in the overall therapeutic landscape of autoimmunity, the design of next-generation antagonists as well as the use of this receptor-targeting principle for other therapeutic applications.

• mester, simone; Chan, Chilam; Lustig, Marta; Foss, Stian; Jansen, J. H. Marco & Herigstad, Marie Leangen [Vis alle 17 forfattere av denne artikkelen] (2025). Engineering of anticancer human immunoglobulin A equipped with albumin for enhanced plasma half-life. PNAS Nexus. 4(2). doi: 10.1093/pnasnexus/pgaf042. Fulltekst i vitenarkiv Vis sammendrag

  Most therapeutic antibodies are based on immunoglobulin G (IgG) due to their potent effector functions and long plasma half-life. However, also monomeric IgA has emerged as an attractive candidate for cancer treatment as, upon specific binding to tumor cells, it can activate myeloid cells, like polymorphonuclear leukocytes and macrophages, to kill the tumor cells by engaging the Fc α receptor I (FcαRI). Despite this favorable property, human IgA has a short plasma half-life in both mice and humans, which is clearly limiting preclinical studies in a translational perspective. Here, we report on albumin-equipped designs of human IgA antibodies that are long acting due to tailored binding to the human form of neonatal Fc receptor (FcRn), which is a natural plasma half-life regulator of albumin. Importantly, this was achieved without compromising the ability of IgA to engage and activate FcαRI-expressing effector cells for tumor cell killing in vitro and in vivo in a new mouse model transgenic for the human forms of FcRn and FcαRI. We further show that the potency of the engineered long-acting human IgA against tumor cells with intermediate target antigen expression levels could be enhanced by myeloid checkpoint inhibitors targeting the signal regulatory protein α-CD47 axis.

• Foss, Stian; Sakya, Siri Aastedatter; Aguinagalde, Leire; Lustig, Marta; Shaughnessy, Jutamas & Cruz, Ana Rita [Vis alle 25 forfattere av denne artikkelen] (2024). Human IgG Fc-engineering for enhanced plasma half-life, mucosal distribution and killing of cancer cells and bacteria. Nature Communications. 15(1). doi: 10.1038/s41467-024-46321-9. Fulltekst i vitenarkiv Vis sammendrag

  Monoclonal IgG antibodies constitute the fastest growing class of therapeutics. Thus, there is an intense interest to design more potent antibody formats, where long plasma half-life is a commercially competitive differentiator affecting dosing, frequency of administration and thereby potentially patient compliance. Here, we report on an Fc-engineered variant with three amino acid substitutions Q311R/M428E/N434W (REW), that enhances plasma half-life and mucosal distribution, as well as allows for needle-free delivery across respiratory epithelial barriers in human FcRn transgenic mice. In addition, the Fc-engineered variant improves on-target complement-mediated killing of cancer cells as well as both gram-positive and gram-negative bacteria. Hence, this versatile Fc technology should be broadly applicable in antibody design aiming for long-acting prophylactic or therapeutic interventions.

• Benjakul, Sopisa; Anthi, Aina Karen; Kolderup, Heidi Anette; Vaysburd, Marina; Lode, Heidrun Elisabeth & Mallery, D [Vis alle 20 forfattere av denne artikkelen] (2023). A pan-SARS-CoV-2-specific soluble angiotensin-converting enzyme 2-albumin fusion engineered for enhanced plasma half-life and needle-free mucosal delivery. PNAS Nexus. 2(12), s. 1–15. doi: 10.1093/pnasnexus/pgad403. Fulltekst i vitenarkiv Vis sammendrag

  Immunocompromised patients often fail to raise protective vaccine-induced immunity against the global emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. Although monoclonal antibodies have been authorized for clinical use, most have lost their ability to potently neutralize the evolving Omicron subvariants. Thus, there is an urgent need for treatment strategies that can provide protection against these and emerging SARS-CoV-2 variants to prevent the development of severe coronavirus disease 2019. Here, we report on the design and characterization of a long-acting viral entry-blocking angiotensin-converting enzyme 2 (ACE2) dimeric fusion molecule. Specifically, a soluble truncated human dimeric ACE2 variant, engineered for improved binding to the receptor-binding domain of SARS-CoV-2, was fused with human albumin tailored for favorable engagement of the neonatal fragment crystallizable receptor (FcRn), which resulted in enhanced plasma half-life and allowed for needle-free transmucosal delivery upon nasal administration in human FcRn-expressing transgenic mice. Importantly, the dimeric ACE2-fused albumin demonstrated potent neutralization of SARS-CoV-2 immune escape variants.

• Frick, Rahel; Høydahl, Lene Støkken; Hodnebrug, Ina; Vik, Erik Sebastian; Dalhus, Bjørn & Sollid, Ludvig Magne [Vis alle 9 forfattere av denne artikkelen] (2022). Affinity maturation of TCR-like antibodies using phage display guided by structural modeling. Protein Engineering Design & Selection. ISSN 1741-0126. 35. doi: 10.1093/protein/gzac005. Fulltekst i vitenarkiv Vis sammendrag

  Abstract TCR-like antibodies represent a unique type of engineered antibodies with specificity toward pHLA, a ligand normally restricted to the sensitive recognition by T cells. Here, we report a phage display-based sequential development path of such antibodies. The strategy goes from initial lead identification through in silico informed CDR engineering in combination with framework engineering for affinity and thermostability optimization, respectively. The strategy allowed the identification of HLA-DQ2.5 gluten peptide-specific TCR-like antibodies with low picomolar affinity. Our method outlines an efficient and general method for development of this promising class of antibodies, which should facilitate their utility including translation to human therapy.

• Foss, Stian; Jonsson, Alexandra; Bottermann, Maria; Watkinson, Ruth; Lode, Heidrun Elisabeth & McAdam, Martin Berner [Vis alle 10 forfattere av denne artikkelen] (2022). Potent TRIM21 and complement-dependent intracellular antiviral immunity requires the IgG3 hinge. Science immunology. 7(70). doi: 10.1126/sciimmunol.abj1640. Fulltekst i vitenarkiv
• Grevys, Algirdas; Frick, Rahel; Mester, Simone; Flem-Karlsen, Karine; Nilsen, Jeannette & Foss, Stian [Vis alle 13 forfattere av denne artikkelen] (2022). Antibody variable sequences have a pronounced effect on cellular transport and plasma half-life. iScience. 25:103746(2), s. 1–22. doi: 10.1016/j.isci.2022.103746. Fulltekst i vitenarkiv Vis sammendrag

  Monoclonal IgG antibodies are the fastest growing class of biologics, but large differences exist in their plasma half-life in humans. Thus, to design IgG antibodies with favorable pharmacokinetics, it is crucial to identify the determinants of such differences. Here, we demonstrate that the variable region sequences of IgG antibodies greatly affect cellular uptake and subsequent recycling and rescue from intracellular degradation by endothelial cells. When the variable sequences are masked by the cognate antigen, it influences both their transport behavior and binding to the neonatal Fc receptor (FcRn), a key regulator of IgG plasma half-life. Furthermore, we show how charge patch differences in the variable domains modulate both binding and transport properties and that a short plasma half-life, due to unfavorable charge patches, may partly be overcome by Fc-engineering for improved FcRn binding.

• Sand, Kine Marita Knudsen; Gruber, Michael M.; Sandlie, Inger; Mathiesen, Line; Andersen, Jan Terje & Wadsack, Christian (2022). Contribution of the ex vivo placental perfusion model in understanding transplacental immunoglobulin G transfer. Placenta. ISSN 0143-4004. 127, s. 77–87. doi: 10.1016/j.placenta.2022.07.019. Fulltekst i vitenarkiv Vis sammendrag

  Introduction The acquisition of humoral immunity in utero is essential for the fetus. The crucial protein, which is responsible for this part of immunity, is immunoglobulin-G (IgG). Immune functions of IgGs are mediated via the interaction of the crystallizable fragment (Fc) region of IgG with specific Fc γ receptors (FcγRs). However, an atypical FcγR, the neonatal Fc receptor (FcRn), is a key regulator of IgG transfer across the human placenta. During the last four decades ex vivo placental perfusion studies have contributed significantly to the study of mechanisms of IgG transfer across the multicellular placental barrier. Method A PubMed search was conducted by using specific keywords: placenta, perfusion and IgG to review manuscripts using human placental perfusion to study the transplacental transfer of IgG. Relevant studies found in reference lists of these manuscripts were also added to the review, and references were included that supported or gave nuance to the discussion of the mechanisms of IgG kinetics in the placenta. Results and Discussion We found twenty publications on the study of transplacental transfer of IgG using human ex vivo placental perfusion, by research groups with partly different settings. This review summarizes knowledge about placental IgG transfer, with a strong focus on the contributions from ex vivo placental perfusion studies.

• Gjølberg, Torleif Tollefsrud; Frick, Rahel; Mester, Simone; Foss, Stian; Grevys, Algirdas & Høydahl, Lene Støkken [Vis alle 11 forfattere av denne artikkelen] (2022). Biophysical differences in IgG1 Fc-based therapeutics relate to their cellular handling, interaction with FcRn and plasma half-life. Communications Biology. 5(1), s. 1–17. doi: 10.1038/s42003-022-03787-x. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Antibody-based therapeutics (ABTs) are used to treat a range of diseases. Most ABTs are either full-length IgG1 antibodies or fusions between for instance antigen (Ag)-binding receptor domains and the IgG1 Fc fragment. Interestingly, their plasma half-life varies considerably, which may relate to how they engage the neonatal Fc receptor (FcRn). As such, there is a need for an in-depth understanding of how different features of ABTs affect FcRn-binding and transport behavior. Here, we report on how FcRn-engagement of the IgG1 Fc fragment compare to clinically relevant IgGs and receptor domain Fc fusions, binding to VEGF or TNF-α. The results reveal FcRn-dependent intracellular accumulation of the Fc, which is in line with shorter plasma half-life than that of full-length IgG1 in human FcRn-expressing mice. Receptor domain fusion to the Fc increases its half-life, but not to the extent of IgG1. This is mirrored by a reduced cellular recycling capacity of the Fc-fusions. In addition, binding of cognate Ag to ABTs show that complexes of similar size undergo cellular transport at different rates, which could be explained by the biophysical properties of each ABT. Thus, the study provides knowledge that should guide tailoring of ABTs regarding optimal cellular sorting and plasma half-life.

• Mester, Simone; Evers, Mitchell; Meyer, Saskia; Nilsen, Jeannette; Greiff, Victor & Sandlie, Inger [Vis alle 8 forfattere av denne artikkelen] (2021). Extended plasma half-life of albumin-binding domain fused human IgA upon pH-dependent albumin engagement of human FcRn in vitro and in vivo. mAbs. ISSN 1942-0862. 13:1893888(1), s. 1–14. doi: 10.1080/19420862.2021.1893888. Fulltekst i vitenarkiv Vis sammendrag

  Albumin has a serum half-life of 3 weeks in humans. This feature can be used to improve the pharmacokinetics of shorter-lived biologics. For instance, an albumin-binding domain (ABD) can be used to recruit albumin. A prerequisite for such design is that the ABD-albumin interaction does not interfere with pH-dependent binding of albumin to the human neonatal Fc receptor (FcRn), as FcRn acts as the principal regulator of the half-life of albumin. Thus, there is a need to know how ABDs act in the context of fusion partners and human FcRn. Here, we studied the binding and transport properties of human immunoglobulin A1 (IgA1), fused to a Streptococcus protein G-derived engineered ABD, in in vitro and in vivo systems harboring human FcRn. IgA has great potential as a therapeutic protein, but its short half-life is a major drawback. We demonstrate that ABD-fused IgA1 binds human FcRn pH-dependently and is rescued from cellular degradation in a receptor-specific manner in the presence of albumin. This occurs when ABD is fused to either the light or the heavy chain. In human FcRn transgenic mice, IgA1-ABD in complex with human albumin, gave 4-6-fold extended half-life compared to unmodified IgA1, where the light chain fusion showed the longest half-life. When the heavy chain-fused protein was pre-incubated with an engineered human albumin with improved FcRn binding, cellular rescue and half-life was further enhanced. Our study reveals how an ABD, which does not interfere with albumin binding to human FcRn, may be used to extend the half-life of IgA.

• Høydahl, Lene; Frigstad, Terje; Rasmussen, Ingunn B; Øynebråten, Inger; Schjetne, Karoline W & Andersen, Jan Terje [Vis alle 10 forfattere av denne artikkelen] (2021). Antibody-mediated delivery of T-cell epitopes to antigen-presenting cells induce strong CD4 and CD8 T-cell responses. Vaccine. ISSN 0264-410X. 39(11), s. 1583–1592. doi: 10.1016/j.vaccine.2021.02.012. Fulltekst i vitenarkiv Vis sammendrag

  Targeted delivery of antigen to antigen-presenting cells (APCs) enhances antigen presentation and thus, is a potent strategy for making more efficacious vaccines. This can be achieved by use of antibodies with specificity for endocytic surface molecules expressed on the APC. We aimed to compare two different antibody-antigen fusion modes in their ability to induce T-cell responses; first, exchange of immunoglobulin (Ig) constant domain loops with a T-cell epitope (Troybody), and second, fusion of T-cell epitope or whole antigen to the antibody C-terminus. Although both strategies are well-established, they have not previously been compared using the same system. We found that both antibody-antigen fusion modes led to presentation of the T-cell epitope. The strength of the T-cell responses varied, however, with the most efficient Troybody inducing CD4 T-cell proliferation and cytokine secretion at 10–100-fold lower concentration than the antibodies carrying antigen fused to the C-terminus, both in vitro and after intravenous injection in mice. Furthermore, we exchanged this loop with an MHCI-restricted T-cell epitope, and the resulting antibody enabled efficient cross-presentation to CD8 T cells in vivo. Targeting of antigen to APCs by use of such antibody-antigen fusions is thus an attractive vaccination strategy for increased activation of both CD4 and CD8 peptide-specific T cells.

• Frick, Rahel; Høydahl, Lene Støkken; Petersen, Jan; Pré, Fleur du; Kumari, Shraddha & Berntsen, Grete [Vis alle 20 forfattere av denne artikkelen] (2021). A high-affinity human TCR-like antibody detects celiac disease gluten peptide-MHC complexes and inhibits T cell activation. Science immunology. 6:eabg4925(62), s. 1–16. doi: 10.1126/sciimmunol.abg4925. Fulltekst i vitenarkiv Vis sammendrag

  Antibodies specific for peptides bound to human leukocyte antigen (HLA) molecules are valuable tools for studies of antigen presentation and may have therapeutic potential. Here, we generated human T cell receptor (TCR)–like antibodies toward the immunodominant signature gluten epitope DQ2.5-glia-α2 in celiac disease (CeD). Phage display selection combined with secondary targeted engineering was used to obtain highly specific antibodies with picomolar affinity. The crystal structure of a Fab fragment of the lead antibody 3.C11 in complex with HLA-DQ2.5:DQ2.5-glia-α2 revealed a binding geometry and interaction mode highly similar to prototypic TCRs specific for the same complex. Assessment of CeD biopsy material confirmed disease specificity and reinforced the notion that abundant plasma cells present antigen in the inflamed CeD gut. Furthermore, 3.C11 specifically inhibited activation and proliferation of gluten-specific CD4+ T cells in vitro and in HLA-DQ2.5 humanized mice, suggesting a potential for targeted intervention without compromising systemic immunity.

• Aaen, Kristin Hovden; Anthi, Aina Karen; Sandlie, Inger; Nilsen, Jeannette; Mester, Simone & Andersen, Jan Terje (2020). The neonatal Fc receptor in mucosal immune regulation. Scandinavian Journal of Immunology. ISSN 0300-9475. doi: 10.1111/sji.13017. Fulltekst i vitenarkiv
• Bern, Malin C.; Nilsen, Jeannette; Ferrarese, Mattia; Sand, Kine Marita Knudsen; Gjølberg, Torleif Tollefsrud & Lode, Heidrun Elisabeth [Vis alle 24 forfattere av denne artikkelen] (2020). An engineered human albumin enhances half-life and transmucosal delivery when fused to protein-based biologics. Science Translational Medicine. ISSN 1946-6234. 12(565), s. 1–13. doi: 10.1126/scitranslmed.abb0580. Fulltekst i vitenarkiv Vis sammendrag

  Needle-free uptake across mucosal barriers is a preferred route for delivery of biologics, but the efficiency of unassisted transmucosal transport is poor. To make administration and therapy efficient and convenient, strategies for the delivery of biologics must enhance both transcellular delivery and plasma half-life. We found that human albumin was transcytosed efficiently across polarized human epithelial cells by a mechanism that depends on the neonatal Fc receptor (FcRn). FcRn also transported immunoglobulin G, but twofold less than albumin. We therefore designed a human albumin variant, E505Q/T527M/K573P (QMP), with improved FcRn binding, resulting in enhanced transcellular transport upon intranasal delivery and extended plasma half-life of albumin in transgenic mice expressing human FcRn. When QMP was fused to recombinant activated coagulation factor VII, the half-life of the fusion molecule increased 3.6-fold compared with the wild-type human albumin fusion, without compromising the therapeutic properties of activated factor VII. Our findings highlight QMP as a suitable carrier of protein-based biologics that may enhance plasma half-life and delivery across mucosal barriers.

• Nilsen, Jeannette; Trabjerg, Esben; Grevys, Algirdas; Azevedo, Claudia; Brennan, Stephen O. & Stensland, Maria [Vis alle 14 forfattere av denne artikkelen] (2020). An intact C-terminal end of albumin is required for its long half-life in humans. Communications Biology. 3(1). doi: 10.1038/s42003-020-0903-7. Fulltekst i vitenarkiv Vis sammendrag

  Albumin has an average plasma half-life of three weeks and is thus an attractive carrier to improve the pharmacokinetics of fused therapeutics. The half-life is regulated by FcRn, a cellular receptor that protects against intracellular degradation. To tailor-design the therapeutic use of albumin, it is crucial to understand how structural alterations in albumin affect FcRn binding and transport properties. In the blood, the last C-terminal residue (L585) of albumin may be enzymatically cleaved. Here we demonstrate that removal of the L585 residue causes structural stabilization in regions of the principal FcRn binding domain and reduces receptor binding. In line with this, a short half-life of only 3.5 days was measured for cleaved albumin lacking L585 in a patient with acute pancreatitis. Thus, we reveal the structural requirement of an intact C-terminal end of albumin for a long plasma half-life, which has implications for design of albumin-based therapeutics.

• Hubbard, Jonathan J.; Pyzik, Michal; Rath, Timo; Kozicky, Lisa K.; Sand, Kine Marita Knudsen & Gandhi, Amit K. [Vis alle 17 forfattere av denne artikkelen] (2020). FcRn is a CD32a coreceptor that determines susceptibility to IgG immune complex-driven autoimmunity. Journal of Experimental Medicine (JEM). ISSN 0022-1007. 217(10). doi: 10.1084/jem.20200359. Fulltekst i vitenarkiv
• Pyzik, Michal; Sand, Kine Marita Knudsen; Hubbard, Jonathan J.; Andersen, Jan Terje; Sandlie, Inger & Blumberg, Richard S. (2019). The neonatal Fc Receptor (FcRn): A misnomer? Frontiers in Immunology. 10:1540(JULY), s. 1–24. doi: 10.3389/fimmu.2019.01540. Fulltekst i vitenarkiv Vis sammendrag

  Antibodies are essential components of an adaptive immune response. Immunoglobulin G (IgG) is the most common type of antibody found in circulation and extracellular fluids. Although IgG alone can directly protect the body from infection through the activities of its antigen binding region, the majority of IgG immune functions are mediated via proteins and receptors expressed by specialized cell subsets that bind to the fragment crystallizable (Fc) region of IgG. Fc gamma (γ) receptors (FcγR) belong to a broad family of proteins that presently include classical membrane-bound surface receptors as well as atypical intracellular receptors and cytoplasmic glycoproteins. Among the atypical FcγRs, the neonatal Fc receptor (FcRn) has increasingly gained notoriety given its intimate influence on IgG biology and its ability to also bind to albumin. FcRn functions as a recycling or transcytosis receptor that is responsible for maintaining IgG and albumin in the circulation, and bidirectionally transporting these two ligands across polarized cellular barriers. More recently, it has been appreciated that FcRn acts as an immune receptor by interacting with and facilitating antigen presentation of peptides derived from IgG immune complexes (IC). Here we review FcRn biology and focus on newer advances including how emerging FcRn-targeted therapies may affect the immune responses to IgG and IgG IC.

• Bottermann, Maria; Foss, Stian; Caddy, Sarah L.; Clift, Dean; Tienen, Laurens M. van & Vaysburd, Marina [Vis alle 16 forfattere av denne artikkelen] (2019). Complement C4 prevents viral infection through capsid inactivation. Cell Host and Microbe. ISSN 1931-3128. 25(4), s. 617–629. doi: 10.1016/j.chom.2019.02.016. Fulltekst i vitenarkiv Vis sammendrag

  The complement system is vital for anti-microbial defense. In the classical pathway, pathogen-bound antibody recruits the C1 complex (C1qC1r2C1s2) that initiates a cleavage cascade involving C2, C3, C4, and C5 and triggering microbial clearance. We demonstrate a C4-dependent antiviral mechanism that is independent of downstream complement components. C4 inhibits human adenovirus infection by directly inactivating the virus capsid. Rapid C4 activation and capsid deposition of cleaved C4b are catalyzed by antibodies via the classical pathway. Capsid-deposited C4b neutralizes infection independent of C2 and C3 but requires C1q antibody engagement. C4b inhibits capsid disassembly, preventing endosomal escape and cytosolic access. C4-deficient mice exhibit heightened viral burdens. Additionally, complement synergizes with the Fc receptor TRIM21 to block transduction by an adenovirus gene therapy vector but is partially restored by Fab virus shielding. These results suggest that the complement system could be altered to prevent virus infection and enhance virus gene therapy efficacy.

• Høydahl, Lene Støkken; Frick, Rahel; Sandlie, Inger & Løset, Geir Åge (2019). Targeting the mhc ligandome by use of tcr-like antibodies. Antibodies. 8:32(2), s. 1–21. doi: 10.3390/antib8020032. Fulltekst i vitenarkiv Vis sammendrag

  Monoclonal antibodies (mAbs) are valuable as research reagents, in diagnosis and in therapy. Their high specificity, the ease in production, favorable biophysical properties and the opportunity to engineer different properties make mAbs a versatile class of biologics. mAbs targeting peptide–major histocompatibility molecule (pMHC) complexes are often referred to as “TCR-like” mAbs, as pMHC complexes are generally recognized by T-cell receptors (TCRs). Presentation of self- and non-self-derived peptide fragments on MHC molecules and subsequent activation of T cells dictate immune responses in health and disease. This includes responses to infectious agents or cancer but also aberrant responses against harmless self-peptides in autoimmune diseases. The ability of TCR-like mAbs to target specific peptides presented on MHC allows for their use to study peptide presentation or for diagnosis and therapy. This extends the scope of conventional mAbs, which are generally limited to cell-surface or soluble antigens. Herein, we review the strategies used to generate TCR-like mAbs and provide a structural comparison with the analogous TCR in pMHC binding. We further discuss their applications as research tools and therapeutic reagents in preclinical models as well as challenges and limitations associated with their use.

• Frick, Rahel; Gunnarsen, Kristin Støen; Dahal-Koirala, Shiva; Risnes, Louise Fremgaard; Sollid, Ludvig Magne & Sandlie, Inger [Vis alle 8 forfattere av denne artikkelen] (2019). A TRAV26-1-encoded recognition motif focuses the biased T cell response in celiac disease. European Journal of Immunology. ISSN 0014-2980. 50, s. 142–145. doi: 10.1002/eji.201948235. Fulltekst i vitenarkiv
• Shaw, Alan; Hoffecker, Ian T.; Smyrlaki, Ioanna; Rosa, João; Grevys, Algirdas & Bryant-Bratlie, Diane Lynn [Vis alle 10 forfattere av denne artikkelen] (2019). Binding to nanopatterned antigens is dominated by the spatial tolerance of antibodies. Nature Nanotechnology. ISSN 1748-3387. 14(2), s. 184–190. doi: 10.1038/s41565-018-0336-3. Fulltekst i vitenarkiv
• Foss, Stian; Bottermann, Maria; Jonsson, Alexandra; Sandlie, Inger; James, Leo C. & Andersen, Jan Terje (2019). TRIM21-From intracellular immunity to therapy. Frontiers in Immunology. 10:2049, s. 1–14. doi: 10.3389/fimmu.2019.02049. Fulltekst i vitenarkiv Vis sammendrag

  Tripartite motif containing-21 (TRIM21) is a cytosolic ubiquitin ligase and antibody receptor that provides a last line of defense against invading viruses. It does so by acting as a sensor that intercepts antibody-coated viruses that have evaded extracellular neutralization and breached the cell membrane. Upon engagement of the Fc of antibodies bound to viruses, TRIM21 triggers a coordinated effector and signaling response that prevents viral replication while at the same time inducing an anti-viral cellular state. This dual effector function is tightly regulated by auto-ubiquitination and phosphorylation. Therapeutically, TRIM21 has been shown to be detrimental in adenovirus based gene therapy, while it may be favorably utilized to prevent tau aggregation in neurodegenerative disorders. In addition, TRIM21 may synergize with the complement system to block viral replication as well as transgene expression. TRIM21 can also be utilized as a research tool to deplete specific proteins in cells and zebrafish embryos. Here, we review our current biological understanding of TRIM21 in light of its versatile functions.

• Høydahl, Lene Støkken; Richter, Lisa Maria; Frick, Rahel; Snir, Omri; Gunnarsen, Kristin Støen & Landsverk, Ole J. B. [Vis alle 18 forfattere av denne artikkelen] (2018). Plasma Cells Are the Most Abundant Gluten Peptide MHC-expressing Cells in Inflamed Intestinal Tissues From Patients With Celiac Disease. Gastroenterology. ISSN 0016-5085. 156(5), s. 1428–1439.e10. doi: 10.1053/j.gastro.2018.12.013. Fulltekst i vitenarkiv Vis sammendrag

  Background & Aims Development of celiac disease is believed to involve the transglutaminase-dependent response of CD4+ T cells toward deamidated gluten peptides in the intestinal mucosa of individuals with specific HLA-DQ haplotypes. We investigated the antigen presentation process during this mucosal immune response. Methods We generated monoclonal antibodies (mAbs) specific for the peptide–MHC (pMHC) complex of HLA-DQ2.5 and the immunodominant gluten epitope DQ2.5-glia-α1a using phage display. We used these mAbs to assess gluten peptide presentation and phenotypes of presenting cells by flow cytometry and enzyme-linked immune absorbent spot (ELISPOT) in freshly prepared single-cell suspensions from intestinal biopsies from 40 patients with celiac disease (35 untreated and 5 on a gluten-free diet) as well as 18 subjects with confirmed noninflamed gut mucosa (controls, 12 presumed healthy, 5 undergoing pancreatoduodenectomy, and 1 with potential celiac disease). Results Using the mAbs, we detected MHC complexes on cells from intestinal biopsies from patients with celiac disease who consume gluten, but not from patients on gluten-free diets. We found B cells and plasma cells to be the most abundant cells that present DQ2.5-glia-α1a in the inflamed mucosa. We identified a subset of plasma cells that expresses B-cell receptors (BCR) specific for gluten peptides or the autoantigen transglutaminase 2 (TG2). Expression of MHC class II (MHCII) was not restricted to these specific plasma cells in patients with celiac disease but was observed in an average 30% of gut plasma cells from patients and controls. Conclusions A population of plasma cells from intestinal biopsies of patients with celiac disease express MHCII; this is the most abundant cell type presenting the immunodominant gluten peptide DQ2.5-glia-α1a in the tissues from these patients. These results indicate that plasma cells in the gut can function as antigen-presenting cells and might promote and maintain intestinal inflammation in patients with celiac disease or other inflammatory disorders.

• Nilsen, Jeannette; Sandlie, Inger; Roopenian, Derry C. & Andersen, Jan Terje (2018). Animal models for evaluation of albumin-based therapeutics. Current Opinion in Chemical Engineering. 19, s. 68–76. doi: 10.1016/j.coche.2017.11.007. Fulltekst i vitenarkiv Vis sammendrag

  Albumin has a long serum half-life due to its unique ability to bind the cellular neonatal Fc receptor (FcRn), which provides protection from intracellular degradation. The interaction can be capitalized to improve the efficacy of drugs by extending their serum persistence. However, species-specific binding of albumin to FcRn Challenges preclinical development. The goal of this brief review is to provide Insights into how FcRn and cross-species binding differences affect the pharmacokinetics of human serum albumin (HSA) in different animal models, and gives an overview of genetically modified mice that may serve as improved models for testing of albumin-based drugs.

• Nilsen, Jeannette; Bern, Malin C.; Sand, Kine Marita Knudsen; Grevys, Algirdas; Dalhus, Bjørn & Sandlie, Inger [Vis alle 7 forfattere av denne artikkelen] (2018). Human and mouse albumin bind their respective neonatal Fc receptors differently. Scientific Reports. 8:14648, s. 1–12. doi: 10.1038/s41598-018-32817-0. Fulltekst i vitenarkiv
• Grevys, Algirdas; Nilsen, Jeannette; Sand, Kine Marita Knudsen; Daba, Muluneh Bekele; Øynebråten, Inger & Bern, Malin C. [Vis alle 15 forfattere av denne artikkelen] (2018). A human endothelial cell-based recycling assay for screening of FcRn targeted molecules. Nature Communications. 9. doi: 10.1038/s41467-018-03061-x. Fulltekst i vitenarkiv Vis sammendrag

  Albumin and IgG have remarkably long serum half-lives due to pH-dependent FcRn-mediated cellular recycling that rescues both ligands from intracellular degradation. Furthermore, increase in half-lives of IgG and albumin-based therapeutics has the potential to improve their efficacies, but there is a great need for robust methods for screening of relative FcRn-dependent recycling ability. Here, we report on a novel human endothelial cell-based recycling assay (HERA) that can be used for such pre-clinical screening. In HERA, rescue from degradation depends on FcRn, and engineered ligands are recycled in a manner that correlates with their half-lives in human FcRn transgenic mice. Thus, HERA is a novel cellular assay that can be used to predict how FcRn-binding proteins are rescued from intracellular degradation.

• Gunnarsen, Kristin Støen; Høydahl, Lene Støkken; Neumann, Ralf Stefan; Bjerregaard-Andersen, Kaare; Nilssen, Nicolay Rustad & Sollid, Ludvig Magne [Vis alle 8 forfattere av denne artikkelen] (2018). Soluble T-cell receptor design influences functional yield in an E. coli chaperone-assisted expression system. PLOS ONE. 13:e0195868(4), s. 1–15. doi: 10.1371/journal.pone.0195868. Fulltekst i vitenarkiv Vis sammendrag

  There is a quest for production of soluble protein of high quality for the study of T-cell receptors (TCRs), but expression often results in low yields of functional molecules. In this study, we used an E. coli chaperone-assisted periplasmic production system and compared expression of 4 different soluble TCR formats: single-chain TCR (scTCR), two different disulfide-linked TCR (dsTCR) formats, and chimeric Fab (cFab). A stabilized version of scTCR was also included. Additionally, we evaluated the influence of host (XL1-Blue or RosettaBlueTM) and the effect of IPTG induction on expression profiles. A celiac disease patient-derived TCR with specificity for gluten was used, and we achieved detectable expression for all formats and variants. We found that expression in RosettaBlueTM without IPTG induction resulted in the highest periplasmic yields. Moreover, after large-scale expression and protein purification, only the scTCR format was obtained in high yields. Importantly, stability engineering of the scTCR was a prerequisite for obtaining reliable biophysical characterization of the TCR-pMHC interaction. The scTCR format is readily compatible with high-throughput screening approaches that may enable both development of reagents allowing for defined peptide MHC (pMHC) characterization and discovery of potential novel therapeutic leads.

• Pyzik, Michal; Rath, Timo; Kuo, Timothy T.; Win, Sanda; Baker, Kristi & Hubbard, Jonathan J. [Vis alle 24 forfattere av denne artikkelen] (2017). Hepatic FcRn regulates albumin homeostasis and susceptibility to liver injury. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 114(14), s. E2862–E2871. doi: 10.1073/pnas.1618291114. Fulltekst i vitenarkiv Vis sammendrag

  The neonatal crystallizable fragment receptor (FcRn) is responsible for maintaining the long half-life and high levels of the two most abundant circulating proteins, albumin and IgG. In the latter case, the protective mechanism derives from FcRn binding to IgG in the weakly acidic environment contained within endosomes of hematopoietic and parenchymal cells, whereupon IgG is diverted from degradation in lysosomes and is recycled. The cellular location and mechanism by which FcRn protects albumin are partially understood. Here we demonstrate that mice with global or liver-specific FcRn deletion exhibit hypoalbuminemia, albumin loss into the bile, and increased albumin levels in the hepatocyte. In vitro models with polarized cells illustrate that FcRn mediates basal recycling and bidirectional transcytosis of albumin and uniquely determines the physiologic release of newly synthesized albumin into the basal milieu. These properties allow hepatic FcRn to mediate albumin delivery and maintenance in the circulation, but they also enhance sensitivity to the albumin-bound hepatotoxin, acetaminophen (APAP). As such, global or liver-specific deletion of FcRn results in resistance to APAP-induced liver injury through increased albumin loss into the bile and increased intracellular albumin scavenging of reactive oxygen species. Further, protection from injury is achieved by pharmacologic blockade of FcRn–albumin interactions with monoclonal antibodies or peptide mimetics, which cause hypoalbuminemia, biliary loss of albumin, and increased intracellular accumulation of albumin in the hepatocyte. Together, these studies demonstrate that the main function of hepatic FcRn is to direct albumin into the circulation, thereby also increasing hepatocyte sensitivity to toxicity.

• Gunnarsen, Kristin Støen; Høydahl, Lene Støkken; Risnes, Louise Fremgaard; Dahal-Koirala, Shiva; Neumann, Ralf Stefan & Bergseng, Elin [Vis alle 15 forfattere av denne artikkelen] (2017). A TCRα framework–centered codon shapes a biased T cell repertoire through direct MHC and CDR3β interactions. JCI Insight. 2(17). doi: 10.1172/jci.insight.95193. Fulltekst i vitenarkiv Vis sammendrag

  Selection of biased T cell receptor (TCR) repertoires across individuals is seen in both infectious diseases and autoimmunity, but the underlying molecular basis leading to these shared repertoires remains unclear. Celiac disease (CD) occurs primarily in HLA-DQ2.5+ individuals and is characterized by a CD4+ T cell response against gluten epitopes dominated by DQ2.5-glia-α1a and DQ2.5-glia-α2. The DQ2.5-glia-α2 response recruits a highly biased TCR repertoire composed of TRAV26-1 paired with TRBV7-2 harboring a semipublic CDR3β loop. We aimed to unravel the molecular basis for this signature. By variable gene segment exchange, directed mutagenesis, and cellular T cell activation studies, we found that TRBV7-3 can substitute for TRBV7-2, as both can contain the canonical CDR3β loop. Furthermore, we identified a pivotal germline-encoded MHC recognition motif centered on framework residue Y40 in TRAV26-1 engaging both DQB1*02 and the canonical CDR3β. This allowed prediction of expanded DQ2.5-glia-α2–reactive TCR repertoires, which were confirmed by single-cell sorting and TCR sequencing from CD patient samples. Our data refine our understanding of how HLA-dependent biased TCR repertoires are selected in the periphery due to germline-encoded residues. This research was originally published in JCI Insight. © 2018 American Society for Clinical Investigation

• Bottermann, Maria; Lode, Heidrun Elisabeth; Watkinson, Ruth E.; Foss, Stian; Sandlie, Inger & Andersen, Jan Terje [Vis alle 7 forfattere av denne artikkelen] (2017). Corrigendum: Antibody-antigen kinetics constrain intracellular humoral immunity. Scientific Reports. doi: 10.1038/srep45418. Fulltekst i vitenarkiv Vis sammendrag

  This Article contains a typographical error in the Methods section under the subheading ‘Crystallization’, where the Protein Data Bank accession code ‘5LDN’ was incorrectly given as ‘5LDV’.

• Michaelsen, Terje Einar; Emilsen, Sidsel; Sandin, Randi Helene; Granerud, Beathe Kiland; Bratlie, Diane Lynn Bryant & Ihle, Øistein [Vis alle 7 forfattere av denne artikkelen] (2017). Human secretory IgM antibodies activate human complement and offer protection at mucosal surface. Scandinavian Journal of Immunology. ISSN 0300-9475. 83(1), s. 43–50. doi: 10.1111/sji.12508. Fulltekst i vitenarkiv
• Foss, Stian; Watkinson, Ruth E; Grevys, Algirdas; Mc, Adam Martin Berner; Bern, Malin C. & Høydahl, Lene Støkken [Vis alle 11 forfattere av denne artikkelen] (2016). TRIM21 Immune Signaling Is More Sensitive to Antibody Affinity Than Its Neutralization Activity. Journal of Immunology. ISSN 0022-1767. 196(8), s. 3452–3459. doi: 10.4049/jimmunol.1502601. Fulltekst i vitenarkiv
• Høydahl, Lene Støkken; Nilssen, Nicolay Rustad; Gunnarsen, Kristin Støen; Pré, Marie Fleur du; Iversen, Rasmus & Roos, Norbert [Vis alle 11 forfattere av denne artikkelen] (2016). Multivalent pIX phage display selects for distinct and improved antibody properties. Scientific Reports. 6. doi: 10.1038/srep39066. Fulltekst i vitenarkiv Vis sammendrag

  Phage display screening readily allows for the identification of a multitude of antibody specificities, but to identify optimal lead candidates remains a challenge. Here, we direct the antibody-capsid fusion away from the signal sequence-dependent secretory SEC pathway in E. coli by utilizing the intrinsic signal sequence-independent property of pIX to obtain virion integration. This approach was combined with the use of an engineered helper phage known to improve antibody pIX display and retrieval. By direct comparison with pIII display, we demonstrate that antibody display using this pIX system translates into substantially improved retrieval of desired specificities with favorable biophysical properties in de novo selection. We show that the effect was due to less E. coli host toxicity during phage propagation conferred by the lack of a signal sequence. This pIX combinatorial display platform provides a generic alternative route for obtaining good binders with high stability and may thus find broad applicability.

• Foss, Stian; Grevys, Algirdas; Sand, Kine Marita Knudsen; Bern, Malin C.; Blundell, Pat & Michaelsen, Terje Einar [Vis alle 9 forfattere av denne artikkelen] (2016). Enhanced FcRn-dependent transepithelial delivery of IgG by Fc-engineering and polymerization. Journal of Controlled Release. ISSN 0168-3659. 223, s. 42–52. doi: 10.1016/j.jconrel.2015.12.033. Fulltekst i vitenarkiv
• Bottermann, Maria; Lode, Heidrun Elisabeth; Watkinson, Ruth E; Foss, Stian; Sandlie, Inger & Andersen, Jan Terje [Vis alle 7 forfattere av denne artikkelen] (2016). Antibody-antigen kinetics constrain intracellular humoral immunity. Scientific Reports. 6. doi: 10.1038/srep37457. Fulltekst i vitenarkiv Vis sammendrag

  During infection with non-enveloped viruses, antibodies stimulate immunity from inside cells by activating the cytosolic Fc receptor TRIM21. This intracellular humoral response relies on opsonized viral particles reaching the cytosol intact but the antigenic and kinetic constraints involved are unknown. We have solved the structure of a potent TRIM21-dependent neutralizing antibody in complex with human adenovirus 5 hexon and show how these properties influence immune activity. Structure-guided mutagenesis was used to generate antibodies with 20,000-fold variation in affinity, on-rates that differ by ~50-fold and off-rates by >175-fold. Characterization of these variants during infection revealed that TRIM21-dependent neutralization and NFκB activation was largely unaffected by on-rate kinetics. In contrast, TRIM21 antiviral activity was exquisitely dependent upon off-rate, with sub-μM affinity antibodies nevertheless unable to stimulate signaling because of fast dissociation kinetics. These results define the antibody properties required to elicit an efficient intracellular immune response during viral infection.

• Grevys, Algirdas; Bern, Malin C.; Foss, Stian; Bratlie, Diane Lynn Bryant; Moen, Anders & Gunnarsen, Kristin Støen [Vis alle 10 forfattere av denne artikkelen] (2015). Fc Engineering of Human IgG1 for Altered Binding to the Neonatal Fc Receptor Affects Fc Effector Functions. Journal of Immunology. ISSN 0022-1767. 194(11), s. 5497–5508. doi: 10.4049/jimmunol.1401218. Fulltekst i vitenarkiv
• Løset, Geir Åge; Berntzen, Gøril; Frigstad, Terje; Pollmann, Sylvie; Gunnarsen, Kristin Støen & Sandlie, Inger (2015). Phage display engineered T cell receptors as tools for the study of tumor peptide–MHC interactions. Frontiers in Oncology. doi: 10.3389/fonc.2014.00378. Fulltekst i vitenarkiv Vis sammendrag

  Cancer immunotherapy has finally come of age, demonstrated by recent progress in strategies that engage the endogenous adaptive immune response in tumor killing. Occasionally, significant and durable tumor regression has been achieved. A giant leap forward was the demonstration that the pre-existing polyclonal T cell repertoire could be re-directed by use of cloned T cell receptors (TCRs), to obtain a defined tumor-specific pool of T cells. However, the procedure must be performed with caution to avoid deleterious cross-reactivity. Here, the use of engineered soluble TCRs may represent a safer, yet powerful, alternative. There is also a need for deeper understanding of the processes that underlie antigen presentation in disease and homeostasis, how tumor-specific peptides are generated, and how epitope spreading evolves during tumor development. Due to its plasticity, the pivotal interaction where a TCR engages a peptide/MHC (pMHC) also requires closer attention. For this purpose, phage display as a tool to evolve cloned TCRs represents an attractive avenue to generate suitable reagents allowing the study of defined pMHC presentation, TCR engagement, as well as for the discovery of novel therapeutic leads. Here, we highlight important aspects of the current status in this field.

• M, Czajkowsky Daniel; Andersen, Jan Terje; Fuchs, Anja; Wilson, Timothy J; Mekhaiel, David & Colonna, Marco [Vis alle 17 forfattere av denne artikkelen] (2015). Developing the IVIG biomimetic, Hexa-Fc, for drug and vaccine applications. Scientific Reports. 5, s. 1–11. doi: 10.1038/srep09526. Fulltekst i vitenarkiv Vis sammendrag

  The remarkable clinical success of Fc-fusion proteins has driven intense investigation for even more potent replacements. Using quality-by-design (QbD) approaches, we generated hexameric-Fc (hexa-Fc), a ~20 nm oligomeric Fc-based scaffold that we here show binds low-affinity inhibitory receptors (FcRL5, FcγRIIb, and DC-SIGN) with high avidity and specificity, whilst eliminating significant clinical limitations of monomeric Fc-fusions for vaccine and/or cancer therapies, in particular their poor ability to activate complement. Mass spectroscopy of hexa-Fc reveals high-mannose, low-sialic acid content, suggesting that interactions with these receptors are influenced by the mannose-containing Fc. Molecular dynamics (MD) simulations provides insight into the mechanisms of hexa-Fc interaction with these receptors and reveals an unexpected orientation of high-mannose glycans on the human Fc that provides greater accessibility to potential binding partners. Finally, we show that this biosynthetic nanoparticle can be engineered to enhance interactions with the human neonatal Fc receptor (FcRn) without loss of the oligomeric structure, a crucial modification for these molecules in therapy and/or vaccine strategies where a long plasma half-life is critical.

• Bern, Malin C.; Sand, Kine Marita Knudsen; Nilsen, Jeannette; Sandlie, Inger & Andersen, Jan Terje (2015). The role of albumin receptors in regulation of albumin homeostasis: Implications for drug delivery. Journal of Controlled Release. ISSN 0168-3659. 211, s. 144–162. doi: 10.1016/j.jconrel.2015.06.006. Fulltekst i vitenarkiv
• Hallstensen, Randi; Bergseth, Grete; Foss, Stian; Jæger, Steinar; Gedde-Dahl, Thobias & Holt, jan [Vis alle 14 forfattere av denne artikkelen] (2015). Eculizumab treatment during pregnancy does not affect the complement system activity of the newborn. Immunobiology. ISSN 0171-2985. 220(4), s. 452–459. doi: 10.1016/j.imbio.2014.11.003. Fulltekst i vitenarkiv Vis sammendrag

  Eculizumab is a humanized IgG2/4 chimeric anti-complement C5 antibody used to treat patients with paroxysmal nocturnal hemoglobinuria (PNH) or atypical hemolytic uremic syndrome. The aim of this study was to evaluate whether or not the complement activity in newborns from pregnant women who receive eculizumab is impaired. A novel eculizumab-C5 complex (E-C5) specific assay was developed and revealed that two newborns carried only 6–7% of the E-C5 detected in their eculizumab-treated PNH mothers. Serum from the pregnant women completely lacked terminal complement pathway activity, whereas the complement activity in the serum of the newborns was completely normal. Data from the pregnant women and their newborns were compared with that of healthy age-matched female controls and healthy newborns, as well as a non-treated pregnant woman with PNH and her newborn. These all showed normal complement activity without detectable E-C5 complexes. Furthermore, absence of eculizumab or E-C5 in the newborn could not be explained by lack of eculizumab binding to the neonatal Fc receptor (FcRn), as eculizumab bound strongly to the receptor in vitro. In conclusion, despite binding to FcRn neither eculizumab nor E-C5 accumulates in fetal plasma, and eculizumab treatment during pregnancy does not impair the complement function in the newborn.

• Sand, Kine Marita Knudsen; Bern, Malin C.; Nilsen, Jeannette; Noordzij, Hanna Theodora; Sandlie, Inger & Andersen, Jan Terje (2015). Unraveling the interaction between FcRn and albumin: Opportunities for design of albumin-based therapeutics. Frontiers in Immunology. 5:682. doi: 10.3389/fimmu.2014.00682. Fulltekst i vitenarkiv Vis sammendrag

  The neonatal Fc receptor (FcRn) was first found to be responsible for transporting antibodies of the immunoglobulin G (IgG) class from the mother to the fetus or neonate as well as for protecting IgG from intracellular catabolism. However, it has now become apparent that the same receptor also binds albumin and plays a fundamental role in homeostatic regulation of both IgG and albumin, as FcRn is expressed in many different cell types and organs at diverse body sites. Thus, to gain a complete understanding of the biological function of each ligand, and also their distribution in the body, an in-depth characterization of how FcRn binds and regulates the transport of both ligands is necessary. Importantly, such knowledge is also relevant when developing new drugs, as IgG and albumin are increasingly utilized in therapy. This review discusses our current structural and biological understanding of the relationship between FcRn and its ligands, with a particular focus on albumin and design of albumin-based therapeutics.

• Foss, Stian; Watkinson, Ruth; Sandlie, Inger; James, Leo C. & Andersen, Jan Terje (2015). TRIM21: A cytosolic Fc receptor with broad antibody isotype specificity. Immunological Reviews. ISSN 0105-2896. 268(1), s. 328–339. doi: 10.1111/imr.12363. Fulltekst i vitenarkiv Vis sammendrag

  Antibodies are key molecules in the fight against infections. Although previously thought to mediate protection solely in the extracellular environment, recent research has revealed that antibody-mediated protection extends to the cytosolic compartment of cells. This postentry viral defense mechanism requires binding of the antibody to a cytosolic Fc receptor named tripartite motif containing 21 (TRIM21). In contrast to other Fc receptors, TRIM21 shows remarkably broad isotype specificity as it does not only bind IgG but also IgM and IgA. When viral pathogens coated with these antibody isotypes enter the cytosol, TRIM21 is rapidly recruited and efficient neutralization occurs before the virus has had the time to replicate. In addition, inflammatory signaling is induced. As such, TRIM21 acts as a cytosolic sensor that engages antibodies that have failed to protect against infection in the extracellular environment. Here, we summarize our current understanding of how TRIM21 orchestrates humoral immunity in the cytosolic environment.

• Rahman, Mohummad Aminur; Kristiansen, Per Eugen; Veiseth, Silje Veie; Andersen, Jan Terje; Yap, Kyoko L. & Zhou, Ming-Ming [Vis alle 9 forfattere av denne artikkelen] (2014). The arabidopsis histone methyltransferase SUVR4 binds ubiquitin via a domain with a four-helix bundle structure. Biochemistry. ISSN 0006-2960. 53(13), s. 2091–2100. doi: 10.1021/bi401436h. Fulltekst i vitenarkiv
• Sand, Kine Marita Knudsen; Bern, Malin C.; Nilsen, Jeannette; Dalhus, Bjørn; Gunnarsen, Kristin Støen & Cameron, Jason [Vis alle 10 forfattere av denne artikkelen] (2014). Interaction with both domain I and III of albumin is required for optimal pH-dependent binding to the neonatal Fc Receptor (FcRn). Journal of Biological Chemistry. ISSN 0021-9258. 289(50), s. 34583–34594. doi: 10.1074/jbc.M114.587675. Fulltekst i vitenarkiv Vis sammendrag

  Albumin is an abundant blood protein that acts as a transporter of a plethora of small molecules like fatty acids, hormones, toxins, and drugs. In addition, it has an unusual long serum half-life in humans of nearly 3 weeks, which is attributed to its interaction with the neonatal Fc receptor (FcRn). FcRn protects albumin from intracellular degradation via a pH-dependent cellular recycling mechanism. To understand how FcRn impacts the role of albumin as a distributor, it is of importance to unravel the structural mechanism that determines pH-dependent binding. Here, we show that although the C-terminal domain III (DIII) of human serum albumin (HSA) contains the principal binding site, the N-terminal domain I (DI) is important for optimal FcRn binding. Specifically, structural inspection of human FcRn (hFcRn) in complex with HSA revealed that two exposed loops of DI were in proximity with the receptor. To investigate to what extent these contacts affected hFcRn binding, we targeted selected amino acid residues of the loops by mutagenesis. Screening by in vitro interaction assays revealed that several of the engineered HSA variants showed decreased binding to hFcRn, which was also the case for two missense variants with mutations within these loops. In addition, four of the variants showed improved binding. Our findings demonstrate that both DI and DIII are required for optimal binding to FcRn, which has implications for our understanding of the FcRn-albumin relationship and how albumin acts as a distributor. Such knowledge may inspire development of novel HSA-based diagnostics and therapeutics. This research was originally published in: Journal of Biological Chemistry. © the American Society for Biochemistry and Molecular Biology.

• Sand, Kine Marita Knudsen; Dalhus, Bjørn; Christianson, Gregory J.; Bern, Malin C.; Foss, Stian & Cameron, Jason [Vis alle 11 forfattere av denne artikkelen] (2014). Dissection of the neonatal Fc receptor (FcRn)-albumin interface using mutagenesis and anti-FcRn albumin-blocking antibodies. Journal of Biological Chemistry. ISSN 0021-9258. doi: 10.1074/jbc.M113.522565. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Dalhus, Bjørn; Viuff, Dorthe; Ravn, Birgitte Thue; Gunnarsen, Kristin Støen & Plumridge, Andrew [Vis alle 17 forfattere av denne artikkelen] (2014). Extending serum half-life of albumin by engineering neonatal Fc receptor (FcRn) binding. Journal of Biological Chemistry. ISSN 0021-9258. 289(19), s. 13492–13502. doi: 10.1074/jbc.M114.549832. Fulltekst i vitenarkiv Vis sammendrag

  A major challenge for the therapeutic use of many peptides and proteins is their short circulatory half-life. Albumin has an extended serum half-life of 3 weeks because of its size and FcRn-mediated recycling that prevents intracellular degradation, properties shared with IgG antibodies. Engineering the strictly pH-dependent IgG-FcRn interaction is known to extend IgG half-life. However, this principle has not been extensively explored for albumin. We have engineered human albumin by introducing single point mutations in the C-terminal end that generated a panel of variants with greatly improved affinities for FcRn. One variant (K573P) with 12-fold improved affinity showed extended serum half-life in normal mice, mice transgenic for human FcRn, and cynomolgus monkeys. Importantly, favorable binding to FcRn was maintained when a single-chain fragment variable antibody was genetically fused to either the N- or the C-terminal end. The engineered albumin variants may be attractive for improving the serum half-life of biopharmaceuticals. This research was originally published in: Journal of Biological Chemistry. © the American Society for Biochemistry and Molecular Biology.

• Sand, Kine Marita Knudsen; Bern, Malin C.; Nilsen, Jeannette; Dalhus, Bjørn; Gunnarsen, Kristin Støen & Cameron, Jason [Vis alle 10 forfattere av denne artikkelen] (2014). Interaction with both domain I and III of albumin is required for optimal pH-dependent binding to the neonatal Fc Receptor (FcRn). Journal of Biological Chemistry. ISSN 0021-9258. 289(50), s. 34583–34594. doi: 10.1074/jbc.M114.587675. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Hjelstuen, Ole Kristian & Sandlie, Inger (2014). From Basic Research to Innovation, Medical Technology - Meeting Tomorrow's Health Care Challenges. Novus Forlag. ISSN 9788270997916. s. 39–50. Fulltekst i vitenarkiv
• Sand, Kine Marita Knudsen; Dalhus, Bjørn; Christianson, Gregory J.; Bern, Malin C.; Foss, Stian & Cameron, Jason [Vis alle 11 forfattere av denne artikkelen] (2014). Dissection of the neonatal Fc receptor (FcRn)-albumin interface using mutagenesis and anti-FcRn albumin-blocking antibodies. Journal of Biological Chemistry. ISSN 0021-9258. 289(24), s. 17228–17239. doi: 10.1074/jbc.M113.522565. Fulltekst i vitenarkiv Vis sammendrag

  Albumin is the most abundant protein in blood and plays a pivotal role as a multitransporter of a wide range of molecules such as fatty acids, metabolites, hormones, and toxins. In addition, it binds a variety of drugs. Its role as distributor is supported by its extraordinary serum half-life of 3 weeks. This is related to its size and binding to the cellular receptor FcRn, which rescues albumin from intracellular degradation. Furthermore, the long half-life has fostered a great and increasing interest in utilization of albumin as a carrier of protein therapeutics and chemical drugs. However, to fully understand how FcRn acts as a regulator of albumin homeostasis and to take advantage of the FcRn-albumin interaction in drug design, the interaction interface needs to be dissected. Here, we used a panel of monoclonal antibodies directed towards human FcRn in combination with site-directed mutagenesis and structural modeling to unmask the binding sites for albumin blocking antibodies and albumin on the receptor, which revealed that the interaction is not only strictly pH-dependent, but predominantly hydrophobic in nature. Specifically, we provide mechanistic evidence for a crucial role of a cluster of conserved tryptophan residues that expose a pH-sensitive loop of FcRn, and identify structural differences in proximity to these hot spot residues that explain divergent cross-species binding properties of FcRn. Our findings expand our knowledge of how FcRn is controlling albumin homeostasis at a molecular level, which will guide design and engineering of novel albumin variants with altered transport properties. This research was originally published in: Journal of Biological Chemistry. © the American Society for Biochemistry and Molecular Biology.

• Mathiesen, Line; Nielsen, Leif K.; Andersen, Jan Terje; Grevys, Algirdas; Sandlie, Inger & Michaelsen, Terje Einar [Vis alle 9 forfattere av denne artikkelen] (2013). Maternofetal transplacental transport of recombinant IgG antibodies lacking effector functions. Blood. ISSN 0006-4971. 122(7), s. 1174–1181. doi: 10.1182/blood-2012-12-473843. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Gonzalez-Pajuelo, Maria; Foss, Stian; Landsverk, Ole J. B.; Pinto, Debora & Szyroki, Alexander [Vis alle 10 forfattere av denne artikkelen] (2013). Selection of Nanobodies that Target Human Neonatal Fc Receptor. Scientific Reports. 3. doi: 10.1038/srep01118. Fulltekst i vitenarkiv Vis sammendrag

  FcRn is a key player in several immunological and non-immunological processes, as it mediates maternal-fetal transfer of IgG, regulates the serum persistence of IgG and albumin, and transports both ligands between different cellular compartments. In addition, FcRn enhances antigen presentation. Thus, there is an intense interest in studies of how FcRn binds and transports its cargo within and across several types of cells, and FcRn detection reagents are in high demand. Here we report on phage display-selected Nanobodies that target human FcRn. The Nanobodies were obtained from a variable-domain repertoire library isolated from a llama immunized with recombinant human FcRn. One candidate, Nb218-H4, was shown to bind FcRn with high affinity at both acidic and neutral pH, without competing ligand binding and interfering with FcRn functions, such as transcytosis of IgG. Thus, Nb218-H4 can be used as a detection probe and as a tracker for visualization of FcRn-mediated cellular transport.

• Andersen, Jan Terje; Cameron, J; Plumridge, A; Sleep, D; Evans, L & Sandlie, Inger (2013). Single-chain Variable Fragment Albumin Fusions Bind the Neonatal Fc Receptor (FcRn) in a Species-dependent Manner: IMPLICATIONS FOR IN VIVO HALF-LIFE EVALUATION OF ALBUMIN FUSION THERAPEUTICS. Journal of Biological Chemistry. ISSN 0021-9258. 288(33), s. 24277–24285. doi: 10.1074/jbc.M113.463000. Fulltekst i vitenarkiv Vis sammendrag

  Albumin has a serum half-life of 3 weeks in humans. This has been utilized to extend the serum persistence of biopharmaceuticals that are fused to albumin. In light of the fact that the neonatal Fc receptor (FcRn) is a key regulator of albumin homeostasis, it is crucial to address how fusion of therapeutics to albumin impacts binding to FcRn. Here, we report on a detailed molecular investigation on how genetic fusion of a short peptide or an single-chain variable fragment (scFv) fragment to human serum albumin (HSA) influences pH-dependent binding to FcRn from mouse, rat, monkey, and human. We have found that fusion to the N- or C-terminal end of HSA only slightly reduces receptor binding, where the most noticeable effect is seen after fusion to the C-terminal end. Furthermore, in contrast to the observed strong binding to human and monkey FcRn, HSA and all HSA fusions bound very poorly to mouse and rat versions of the receptor. Thus, we demonstrate that conventional rodents are limited as preclinical models for analysis of serum half-life of HSA-based biopharmaceuticals. This finding is explained by cross-species differences mainly found within domain III (DIII) of albumin. Our data demonstrate that although fusion, particularly to the C-terminal end, may slightly reduce the affinity for FcRn, HSA is versatile as a carrier of biopharmaceuticals. This research was originally published in: Journal of Biological Chemistry. © the American Society for Biochemistry and Molecular Biology.

• Yazaki, Paul J.; Lee, Brian; Channappal, Divya; Cheung, Chia-Wei; Crow, Desiree & Chea, Junie [Vis alle 15 forfattere av denne artikkelen] (2013). A series of anti-CEA/anti-DOTA bispecific antibody formats evaluated for pre-targeting: comparison of tumor uptake and blood clearance. Protein Engineering Design & Selection. ISSN 1741-0126. 26(3), s. 187–193. doi: 10.1093/protein/gzs096. Fulltekst i vitenarkiv
• Jung, Sang Taek; Kelton, William; Kang, Tae Hyun; Ng, Daphne T.W.; Andersen, Jan Terje & Sandlie, Inger [Vis alle 8 forfattere av denne artikkelen] (2013). Effective Phagocytosis of Low Her2 Tumor Cell Lines with Engineered, Aglycosylated IgG Displaying High FcγRIIa Affinity and Selectivity. ACS Chemical Biology. ISSN 1554-8929. 8(2), s. 368–375. doi: 10.1021/cb300455f. Fulltekst i vitenarkiv
• Lau, Corinna; Gunnarsen, Kristin Støen; Høydahl, Lene Støkken; Andersen, Jan Terje; Berntzen, Gøril & Pharo, Anne Margrethe [Vis alle 15 forfattere av denne artikkelen] (2013). Chimeric Anti-CD14 IGG2/4 Hybrid Antibodies for Therapeutic Intervention in Pig and Human Models of Inflammation. Journal of Immunology. ISSN 0022-1767. 191(9), s. 4769–4777. doi: 10.4049/jimmunol.1301653. Fulltekst i vitenarkiv Vis sammendrag

  CD14 is a key recognition molecule of innate immune responses, interacting with several TLRs. TLR signaling cross-talks extensively with the complement system, and combined CD14 and complement inhibition has been proved effective in attenuating inflammatory responses. Pig models of human diseases have emerged as valuable tools to study therapeutic intervention, but suitable neutralizing Abs are rare. Undesired Fc-mediated functions, such as platelet activation and IL-8 release induced by the porcine CD14-specific clone Mil2, limit further studies. Therefore, an inert human IgG2/IgG4 hybrid C region was chosen for an rMil2. As revealed in ex vivo and in vivo pig experiments, rMil2 inhibited the CD14-mediated proinflammatory cytokine response similar to the original clone, but lacked the undesired Fc-effects, and inflammation was attenuated further by simultaneous complement inhibition. Moreover, rMil2 bound porcine FcRn, a regulator of t1/2 and biodistribution. Thus, rMil2, particularly combined with complement inhibitors, should be well suited for in vivo studies using porcine models of diseases, such as sepsis and ischemia-reperfusion injury. Similarly, the recombinant anti-human CD14 IgG2/4 Ab, r18D11, was generated with greatly reduced Fc-mediated effects and preserved inhibitory function ex vivo. Such Abs might be drug candidates for the treatment of innate immunity-mediated human diseases.

• Frigstad, Terje; Løset, Geir Åge; Sandlie, Inger & Bogen, Bjarne (2013). A Public T cell Receptor Recognized by a MonoclonalAntibody Specific for the D-J Junction of the b-chain. Scandinavian Journal of Immunology. ISSN 0300-9475. s. 345–351. doi: 10.1111/sji.12098. Fulltekst i vitenarkiv
• Gunnarsen, Kristin Støen; Kristinsson, Solveig Gunn; Justesen, Sune; Frigstad, Terje; Buus, Søren & Bogen, Bjarne [Vis alle 8 forfattere av denne artikkelen] (2013). Chaperone-assisted thermostability engineering of a soluble T cell receptor using phage display. Scientific Reports. 3. doi: 10.1038/srep01162. Fulltekst i vitenarkiv Vis sammendrag

  We here report a novel phage display selection strategy enabling fast and easy selection of thermostabilized proteins. The approach is illustrated with stabilization of an aggregation-prone soluble single chain T cell receptor (scTCR) characteristic of the murine MOPC315 myeloma model. Random mutation scTCR phage libraries were prepared in E. coli over-expressing the periplasmic chaperone FkpA, and such over-expression during library preparation proved crucial for successful downstream selection. The thermostabilized scTCRmut variants selected were produced in high yields and isolated as monomers. Thus, the purified scTCRs could be studied with regard to specificity and equilibrium binding kinetics to pMHC using surface plasmon resonance (SPR). The results demonstrate a difference in affinity for pMHCs that display germ line or tumor-specific peptides which explains the tumor-specific reactivity of the TCR. This FkpA-assisted thermostabilization strategy extends the utility of recombinant TCRs and furthermore, may be of general use for efficient evolution of proteins.

• Løset, Geir Åge & Sandlie, Inger (2012). Next generation phage display by use of pVII and pIX as display scaffolds. Methods. ISSN 1046-2023. 58(1), s. 40–46. doi: 10.1016/j.ymeth.2012.07.005. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Dalhus, Bjørn; Cameron, Jason; Daba, Muluneh Bekele; Plumridge, Andrew & Evans, Leslie [Vis alle 11 forfattere av denne artikkelen] (2012). Structure-based mutagenesis reveals the albumin-binding site of the neonatal Fc receptor. Nature Communications. 3. doi: 10.1038/ncomms1607. Fulltekst i vitenarkiv Vis sammendrag

  Albumin is the most abundant protein in blood where it has a pivotal role as a transporter of fatty acids and drugs. Like IgG, albumin has long serum half-life, protected from degradation by pH-dependent recycling mediated by interaction with the neonatal Fc receptor, FcRn. Although the FcRn interaction with IgG is well characterized at the atomic level, its interaction with albumin is not. Here we present structure-based modelling of the FcRn–albumin complex, supported by binding analysis of site-specific mutants, providing mechanistic evidence for the presence of pH-sensitive ionic networks at the interaction interface. These networks involve conserved histidines in both FcRn and albumin domain III. Histidines also contribute to intramolecular interactions that stabilize the otherwise flexible loops at both the interacting surfaces. Molecular details of the FcRn–albumin complex may guide the development of novel albumin variants with altered serum half-life as carriers of drugs.

• Nilssen, Nicolay Rustad; Frigstad, Terje; Pollmann, Sylvie; Roos, Norbert; Bogen, Bjarne & Sandlie, Inger [Vis alle 7 forfattere av denne artikkelen] (2012). DeltaPhage-a novel helper phage for high-valence pIX phagemid display. Nucleic Acids Research (NAR). ISSN 0305-1048. 40(16). doi: 10.1093/nar/gks341. Fulltekst i vitenarkiv Vis sammendrag

  Phage display has been instrumental in discovery of novel binding peptides and folded domains for the past two decades. We recently reported a novel pIX phagemid display system that is characterized by a strong preference for phagemid packaging combined with low display levels, two key features that support highly efficient affinity selection. However, high diversity in selected repertoires are intimately coupled to high display levels during initial selection rounds. To incorporate this additional feature into the pIX display system, we have developed a novel helper phage termed DeltaPhage that allows for high-valence display on pIX. This was obtained by inserting two amber mutations close to the pIX start codon, but after the pVII translational stop, conditionally inactivating the helper phage encoded pIX. Until now, the general notion has been that display on pIX is dependent on wild-type complementation, making high-valence display unachievable. However, we found that DeltaPhage does facilitate high-valence pIX display when used with a non-suppressor host. Here, we report a side-by-side comparison with pIII display, and we find that this novel helper phage complements existing pIX phagemid display systems to allow both low and high-valence display, making pIX display a complete and efficient alternative to existing pIII phagemid display systems.

• Fredriksen, Agnete; Sandlie, Inger & Bogen, Bjarne (2012). Targeted DNA vaccines for enhanced induction of idiotype-specific B and T cells. Frontiers in Oncology. 2. doi: 10.3389/fonc.2012.00154. Fulltekst i vitenarkiv Vis sammendrag

  Background: Idiotypes (Id) are antigenic determinants localized in variable (V) regions of Ig. Id-specific T and B cells (antibodies) play a role in immunotherapy of Id+ tumors. However, vaccine strategies that enhance Id-specific responses are needed. Methods: Id+ single-chain fragment variable (scFv) from multiple myelomas and B cell lymphomas were prepared in a fusion format that bivalently target surface molecules on antigen-presenting cells (APC). APC-specific targeting units were either scFv from APC-specific mAb (anti-MHC II, anti-CD40) or chemokines (MIP-1α, RANTES). Homodimeric Id-vaccines were injected intramuscularly or intradermally as plasmids in mice, combined with electroporation. Results: (i) Transfected cells secreted plasmid-encoded Id+ fusion proteins to extracellular fluid followed by binding of vaccine molecules to APC. (ii) Targeted vaccine molecules increased Id-specific B and T cell responses. (iii) Bivalency and xenogeneic sequences both contributed to enhanced responses. (iv) Targeted Id DNA vaccines induced tumor resistance against challenges with Id+ tumors. (v) Human MIP-1α targeting units enhanced Id-specific responses in mice, due to a cross reaction with murine chemokine receptors. Thus, targeted vaccines designed for humans can be quality tested in mice. (vi) Human Id+ scFv from four multiple myeloma patients were inserted into the vaccine format and were successfully tested in mice. (vii) Human MIP-1α vaccine proteins enhanced human T cell responses in vitro. (viii) A hypothetical model for how the APC-targeted vaccine molecules enhance Id-specific T and B cells is presented. Conclusion: Targeted DNA Id-vaccines show promising results in preclinical studies, paving the way for testing in patients.

• Andersen, Jan Terje; Foss, Stian; Kenanova, Vania E; Olafsen, Tove; Leikfoss, Ingvild Sørum & Roopenian, Derry C [Vis alle 8 forfattere av denne artikkelen] (2012). Anti-carcinoembryonic Antigen Single-chain Variable Fragment Antibody Variants Bind Mouse and Human Neonatal Fc Receptor with Different Affinities That Reveal Distinct Cross-species Differences in Serum Half-life. Journal of Biological Chemistry. ISSN 0021-9258. 287(27), s. 22927–22937. doi: 10.1074/jbc.M112.355131. Fulltekst i vitenarkiv Vis sammendrag

  Serum half-life of IgG is controlled by the neonatal Fc receptor (FcRn) that interacts with the IgG Fc region and may be increased or decreased as a function of altered FcRn binding. Preclinical evaluations of modified IgGs are frequently carried out in mice, but such IgGs may bind differently to mouse and human FcRn (mFcRn and hFcRn). Here, we report a detailed characterization of a matched set of mouse-human chimeric T84.66 scFv-Fc variants with specificity for the tumor carcinoembryonic antigen and mutations in the FcRn-binding site. Binding to soluble mFcRn and hFcRn was measured using in vitro assays, and the results were compared with blood clearance in vivo in normal (mFcRn bearing) and hFcRn transgenic mice. All variants bound better to mFcRn than to hFcRn. The loss of affinity varied among the mutants, however, and also the hierarchy of binding differed depending on the receptor. The mutations had no major impact on binding to the classical Fcγ receptors. Importantly, the trend of blood clearance in both strains of mice correlated with the hierarchy of binding obtained using soluble FcRn. Consequently, in vitro interaction analysis of engineered IgGs regarding their cross-species FcRn binding ability provides information for prediction of in vivo pharmacokinetics. This research was originally published in: Journal of Biological Chemistry. © the American Society for Biochemistry and Molecular Biology.

• Rasmussen, Ingunn B; Øynebråten, Inger; Høydahl, Lene Støkken; Flobakk, Morten; Lunde, Elin & Michaelsen, Terje Einar [Vis alle 8 forfattere av denne artikkelen] (2012). CD40/APC-specific antibodies with three T-cell epitopes loaded in the constant domains induce CD4 T-cell responses. Protein Engineering Design & Selection. ISSN 1741-0126. 25(3), s. 89–96. doi: 10.1093/protein/gzr063. Fulltekst i vitenarkiv
• Stapleton, NM; Andersen, Jan Terje; Stemerding, AM; Bjarnarson, SP; Verheul, RC & Gerritsen, J. [Vis alle 13 forfattere av denne artikkelen] (2011). Competition for FcRn-mediated transport gives rise to short half-life of human IgG3 and offers therapeutic potential. Nature Communications. 2. doi: 10.1038/ncomms1608. Fulltekst i vitenarkiv Vis sammendrag

  Human IgG3 displays the strongest effector functions of all IgG subclasses but has a short half-life for unresolved reasons. Here we show that IgG3 binds to IgG-salvage receptor (FcRn), but that FcRn-mediated transport and rescue of IgG3 is inhibited in the presence of IgG1 due to intracellular competition between IgG1 and IgG3. We reveal that this occurs because of a single amino acid difference at position 435, where IgG3 has an arginine instead of the histidine found in all other IgG subclasses. While the presence of R435 in IgG increases binding to FcRn at neutral pH, it decreases binding at acidic pH, affecting the rescue effi ciency-but only in the presence of H435-IgG. Importantly, we show that in humans the half-life of the H435containing IgG3 allotype is comparable to IgG1. H435-IgG3 also gave enhanced protection against a pneumococcal challenge in mice, demonstrating H435-IgG3 to be a candidate for monoclonal antibody therapies.

• Løset, Geir Åge; Roos, Norbert; Bogen, Bjarne & Sandlie, Inger (2011). Expanding the Versatility of Phage Display II: Improved Affinity Selection of Folded Domains on Protein VII and IX of the Filamentous Phage. PLOS ONE. 6(2). doi: 10.1371/journal.pone.0017433. Fulltekst i vitenarkiv Vis sammendrag

  Background: Phage display is a leading technology for selection of binders with affinity for specific target molecules. Polypeptides are normally displayed as fusions to the major coat protein VIII (pVIII) or the minor coat protein III (pIII). Whereas pVIII display suffers from drawbacks such as heterogeneity in display levels and polypeptide fusion size limitations, toxicity and infection interference effects have been described for pIII display. Thus, display on other coat proteins such as pVII or pIX might be more attractive. Neither pVII nor pIX display have gained widespread use or been characterized in detail like pIII and pVIII display. Methodology/Principal Findings: Here we present a side-by-side comparison of display on pIII with display on pVII and pIX. Polypeptides of interest (POIs) are fused to pVII or pIX. The N-terminal periplasmic signal sequence, which is required for phage integration of pIII and pVIII and that has been added to pVII and pIX in earlier studies, is omitted altogether. Although the POI display level on pIII is higher than on pVII and pIX, affinity selection with pVII and pIX display libraries is shown to be particularly efficient. Conclusions/Significance: Display through pVII and/or pIX represent platforms with characteristics that differ from those of the pIII platform. We have explored this to increase the performance and expand the use of phage display. In the paper, we describe effective affinity selection of folded domains displayed on pVII or pIX. This makes both platforms more attractive alternatives to conventional pIII and pVIII display than they were before. © 2011 Wälchli et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

• Qiao, Shuo Wang; Raki, Melinda; Gunnarsen, Kristin Støen; Løset, Geir Åge; Lundin, Knut E A & Sandlie, Inger [Vis alle 7 forfattere av denne artikkelen] (2011). Posttranslational Modification of Gluten Shapes TCR Usage in Celiac Disease. Journal of Immunology. ISSN 0022-1767. 187(6), s. 3064–3071. doi: 10.4049/jimmunol.1101526. Fulltekst i vitenarkiv
• Løset, Geir Åge; Bogen, Bjarne & Sandlie, Inger (2011). Expanding the Versatility of Phage Display I: Efficient Display of Peptide-Tags on Protein VII of the Filamentous Phage. PLOS ONE. 6(2). doi: 10.1371/journal.pone.0014702. Fulltekst i vitenarkiv Vis sammendrag

  Background: Phage display is a platform for selection of specific binding molecules and this is a clear-cut motivation for increasing its performance. Polypeptides are normally displayed as fusions to the major coat protein VIII (pVIII), or the minor coat protein III (pIII). Display on other coat proteins such as pVII allows for display of heterologous peptide sequences on the virions in addition to those displayed on pIII and pVIII. In addition, pVII display is an alternative to pIII or pVIII display. Methodology/Principal Findings: Here we demonstrate how standard pIII or pVIII display phagemids are complemented with a helper phage which supports production of virions that are tagged with octa FLAG, HIS6 or AviTag on pVII. The periplasmic signal sequence required for pIII and pVIII display, and which has been added to pVII in earlier studies, is omitted altogether. Conclusions/Significance: Tagging on pVII is an important and very useful add-on feature to standard pIII and pVII display. Any phagemid bearing a protein of interest on either pIII or pVIII can be tagged with any of the tags depending simply on choice of helper phage. We show in this paper how such tags may be utilized for immobilization and separation as well as purification and detection of monoclonal and polyclonal phage populations. © 2011 Wälchli et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

• Mekhaiel, David N. A.; Czajkowsky, Daniel M.; Andersen, Jan Terje; Shi, Jianguo; El-Faham, Marwa & Doenhoff, Michael [Vis alle 12 forfattere av denne artikkelen] (2011). Polymeric human Fc-fusion proteins with modified effector functions. Scientific Reports. 1. doi: 10.1038/srep00124. Fulltekst i vitenarkiv Vis sammendrag

  The success of Fc-fusion bio-therapeutics has spurred the development of other Fc-fusion products for treating and/or vaccinating against a range of diseases. We describe a method to modulate their function by converting them into well-defined stable polymers. This strategy resulted in cylindrical hexameric structures revealed by tapping mode atomic force microscopy (AFM). Polymeric Fc-fusions were significantly less immunogenic than their dimeric or monomeric counterparts, a result partly owing to their reduced ability to interact with critical Fc-receptors. However, in the absence of the fusion partner, polymeric IgG1-Fc molecules were capable of binding selectively to FcγRs, with significantly increased affinity owing to their increased valency, suggesting that these reagents may prove of immediate utility in the development of well-defined replacements for intravenous immunoglobulin (IVIG) therapy. Overall, these findings establish an effective IgG Fc-fusion based polymeric platform with which the therapeutic and vaccination applications of Fc-fusion immune-complexes can now be explored.

• Baker, Kristi; Qiao, Shuo Wang; Kuo, Timothy T.; Aveson, Victoria G.; Platzer, Barbara & Andersen, Jan Terje [Vis alle 12 forfattere av denne artikkelen] (2011). Neonatal Fc receptor for IgG (FcRn) regulates cross-presentation of IgG immune complexes by CD8(-)CD11b(+) dendritic cells. Proceedings of the National Academy of Sciences of the United States of America (PNAS). ISSN 0027-8424. 108(24), s. 9927–9932. doi: 10.1073/pnas.1019037108. Fulltekst i vitenarkiv
• Wälchli, Sebastien; Løset, Geir Åge; Kumari, Shraddha; Johansen, Jorunn; Yang, Weiwen & Sandlie, Inger [Vis alle 7 forfattere av denne artikkelen] (2011). A Practical Approach to T-Cell Receptor Cloning and Expression. PLOS ONE. 6(11). doi: 10.1371/journal.pone.0027930. Fulltekst i vitenarkiv Vis sammendrag

  Although cloning and expression of T-cell Receptors (TcRs) has been performed for almost two decades, these procedures are still challenging. For example, the use of T-cell clones that have undergone limited expansion as starting material to limit the loss of interesting TcRs, must be weighed against the introduction of mutations by excess PCR cycles. The recent interest in using specific TcRs for cancer immunotherapy has, however, increased the demand for practical and robust methods to rapidly clone and express TcRs. Two main technologies for TcR cloning have emerged; the use of a set of primers specifically annealing to all known TcR variable domains, and 59-RACE amplification. We here present an improved 59-RACE protocol that represents a fast and reliable way to identify a TcR from 105 cells only, making TcR cloning feasible without a priori knowledge of the variable domain sequence. We further present a detailed procedure for the subcloning of TcRa and b chains into an expression system. We show that a recombination-based cloning protocol facilitates simple and rapid transfer of the TcR transgene into different expression systems. The presented comprehensive method can be performed in any laboratory with standard equipment and with a limited amount of starting material. We finally exemplify the straightforwardness and reliability of our procedure by cloning and expressing several MART-1-specific TcRs and demonstrating their functionality. © 2011 Wälchli et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

• Gunnarsen, Kristin Støen; Lunde, Elin; Kristiansen, Per Eugen; Bogen, Bjarne; Sandlie, Inger & Løset, Geir Åge (2010). Periplasmic expression of soluble single chain T cell receptors is rescued by the chaperone FkpA. BMC Biotechnology. 10. doi: 10.1186/1472-6750-10-8. Fulltekst i vitenarkiv Vis sammendrag

  Background Efficient expression systems exist for antibody (Ab) molecules, which allow for characterization of large numbers of individual Ab variants. In contrast, such expression systems have been lacking for soluble T cell receptors (TCRs). Attempts to generate bacterial systems have generally resulted in low yields and material which is prone to aggregation and proteolysis. Here we present an optimized periplasmic bacterial expression system for soluble single chain (sc) TCRs. Results The effect of 1) over-expression of the periplasmic chaperon FkpA, 2) culture conditions and 3) molecular design was investigated. Elevated levels of FkpA allowed periplasmic soluble scTCR expression, presumably by preventing premature aggregation and inclusion body formation. Periplasmic expression enables disulphide bond formation, which is a prerequisite for the scTCR to reach its correct fold. It also enables quick and easy recovery of correctly folded protein without the need for time-consuming downstream processing. Expression without IPTG induction further improved the periplasmic expression yield, while addition of sucrose to the growth medium showed little effect. Shaker flask yield of mg levels of active purified material was obtained. The Vαβ domain orientation was far superior to the Vβα domain orientation regarding monomeric yield of functionally folded molecules. Conclusion The general expression regime presented here allows for rapid production of soluble scTCRs and is applicable for 1) high yield recovery sufficient for biophysical characterization and 2) high throughput screening of such molecules following molecular engineering.

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• Andersen, Jan Terje & Sandlie, Inger (2011). Extending Antibody Half Lives with Albumin In: Recombinant Antibodies for Immunotherapy. Cambridge University Press. ISBN 9780521887328. 17 s. Fulltekst i vitenarkiv
• Andersen, Jan Terje & Sandlie, Inger (2011). Pharmacokinetics of IgG and albumin: The impact of FcRn for Design of Drug Delivery Systems: The impact of FcRn for Design of Drug Delivery Systems. Wiley-VCH Verlag GmbH. ISBN 9783527328239. 34 s. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Ruso-Julve, Fulgencio; Sakya, Siri A; Kolderup, Heidi Anette; Tjärnhage, Elias; Benjakul, Sopisa & Nilsen, Jeannette [Vis alle 10 forfattere av denne artikkelen] (2024). Engineered human albumin as an effector negative scaffold for tailored design of long-acting antibody fragment fusions. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Benjakul, Sopisa; Anthi, Aina Karen; Kolderup, Heidi Anette & Sandlie, Inger (2023). Et skreddersydd protein - designet av forskere i OUS - jakter koronaviruset. doi: https:/www.oslo-universitetssykehus.no/om-oss/innsikt/et-skredersydd-protein---designet-av-forskere-i-ous---jakter-coronaviruset/. Fulltekst i vitenarkiv
• Anthi, Aina Karen; Kolderup, Heidi Anette; Vaage, Eline Benno; Bern, Malin C.; Benjakul, Sopisa & Tjärnhage, Elias [Vis alle 30 forfattere av denne artikkelen] (2023). A novel non-invasive FcRn-targeted mucosal vaccine strategy. Fulltekst i vitenarkiv
• Anthi, Aina Karen; mester, simone; Bern, Malin C.; Sandlie, Inger & Andersen, Jan Terje (2023). HemoMagic: Anemia Meets Unleashed Innovation. Fulltekst i vitenarkiv
• Anthi, Aina Karen; Kolderup, Heidi Anette; Vaage, Eline Benno; Bern, Malin C.; Benjakul, Sopisa & Tjärnhage, Elias [Vis alle 30 forfattere av denne artikkelen] (2023). A non-invasive subunit vaccine technology targeting FcRn induces protective mucosal and systemic antibody immunity in mouse models. Fulltekst i vitenarkiv
• Anthi, Aina Karen; Kolderup, Heidi Anette; Vaage, Eline Benno; Bern, Malin C.; Benjakul, Sopisa & Tjärnhage, Elias [Vis alle 30 forfattere av denne artikkelen] (2023). A novel non-invasive FcRn-targeted mucosal vaccine strategy. Fulltekst i vitenarkiv
• Anthi, Aina Karen; Vaage, Eline Benno; Bern, Malin C.; Benjakul, Sopisa; Tjärnhage, Elias & Lode, Heidrun Elisabeth [Vis alle 29 forfattere av denne artikkelen] (2023). A non-invasive subunit vaccine technology targeting FcRn induces protective mucosal and systemic antibody immunity in mouse models. Fulltekst i vitenarkiv
• Ruso-Julve, Fulgencio; Sakya, Siri A; Lode, Heidrun Elisabeth; Foss, Stian; Benjakul, Sopisa & Nilsen, Jeannette [Vis alle 10 forfattere av denne artikkelen] (2022). Engineered albumin as a scaffold for improving the pharmacokinetic properties of antibody fragments. Fulltekst i vitenarkiv
• Shaw, Alan; Hoffecker, Ian T.; Smyrlaki, Ioanna; Rosa, João; Grevys, Algirdas & Bryant-Bratlie, Diane Lynn [Vis alle 10 forfattere av denne artikkelen] (2019). Publisher Correction: Binding to nanopatterned antigens is dominated by the spatial tolerance of antibodies. Nature Nanotechnology. ISSN 1748-3387. 14(4), s. 398–398. doi: 10.1038/s41565-019-0404-3. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Sakya, Siri Aastedatter; Foss, Stian; Sandlie, Inger & Voets, Ardi (2019). Is an HIV vaccine within reach? Vaksinebloggen. Fulltekst i vitenarkiv
• Andersen, Jan Terje; Sakya, Siri Aastedatter; Foss, Stian & Sandlie, Inger (2019). Hvordan kan moderne medisin forebygge HIV? Medisinbloggen. Fulltekst i vitenarkiv
• Frich, Jan C; Graver, Hans Petter & Sandlie, Inger (2017). Slik blir Team Gravers læringsstrategi. Universitas. Fulltekst i vitenarkiv
• Frich, Jan C; Graver, Hans Petter & Sandlie, Inger (2017). Hvorfor begrunne karakteren? Universitas. Fulltekst i vitenarkiv
• Graver, Hans Petter; Sandlie, Inger & Frich, Jan C (2017). Rektorteam Graver/Sandlie/Frich: Ledelse og administrasjon. Uniforum. ISSN 1891-5825. Fulltekst i vitenarkiv
• Frich, Jan C; Graver, Hans Petter & Sandlie, Inger (2017). Slik skal team Graver, Sandlie & Frich gjøre UiO til læringsuniversitetet. Uniforum. ISSN 1891-5825. Fulltekst i vitenarkiv
• Graver, Hans Petter; Sandlie, Inger & Frich, Jan C (2017). Forvandle vår verden | Graver, Sandlie og Frich. s. 18–19. Fulltekst i vitenarkiv
• Sandlie, Inger; Graver, Hans Petter & Frich, Jan C (2017). Mindre midlertidighet. Klassekampen. ISSN 0805-3839. s. 24–24. Fulltekst i vitenarkiv
• Mandecki, W.; Goldman, E.; Sandlie, Inger & Løset, Geir Åge (2015). Phage Display and Selection of Protein Ligands. I Goldman, Emanuel & Green, Laurence (Red.), Practical Handbook of Microbiology, Third Edition. CRC Press. ISSN 9781466587397. s. 101–114. Fulltekst i vitenarkiv
• Lau, Corinna; Gunnarsen, Kristin Støen; Høydahl, Lene Støkken; Berntzen, Gøril; Stokes, Christopher R. & Espevik, Terje [Vis alle 8 forfattere av denne artikkelen] (2012). Recombinant anti-human and anti-porcine CD14 antibodies. Immunobiology. ISSN 0171-2985. 217(11), s. 1197–1198. doi: 10.1016/j.imbio.2012.08.196. Fulltekst i vitenarkiv
• Høydahl, Lene Støkken; Neumann, Ralf Stefan; Qiao, Shuo Wang; Sollid, Ludvig Magne; Sandlie, Inger & Løset, Geir Åge (2011). Development of a High Affinity TCR Reagent by Phage Display to Study Antigen Presentation in Celiac Disease. Scandinavian Journal of Immunology. ISSN 0300-9475. 73(4), s. 372–372. Fulltekst i vitenarkiv
• Qiao, Shuo Wang; Raki, Melinda; Gunnarsen, Kristin Støen; Løset, Geir Åge; Sandlie, Inger & Sollid, Ludvig Magne (2011). Post-Translational Modification of Gluten Shapes the T Cell Response in Coeliac Disease by Direct Interaction with the T Cell Receptor. Scandinavian Journal of Immunology. ISSN 0300-9475. 73(4), s. 356–356. Fulltekst i vitenarkiv
• Gunnarsen, Kristin Støen; Kristinsson, Solveig Gunn; Bogen, Bjarne; Sandlie, Inger & Løset, Geir Åge (2011). Thermostability Engineering of a Soluble Single Chain T Cell Receptor (scTCR) Using Phage Display. Scandinavian Journal of Immunology. ISSN 0300-9475. 73(4), s. 352–352. Fulltekst i vitenarkiv
• Foss, Stian; Michaelsen, Terje Einar; Sandlie, Inger & Andersen, Jan Terje (2011). The Influence of Removal of the IgG Fab Arms on Binding to FcRn. Scandinavian Journal of Immunology. ISSN 0300-9475. 73(4), s. 350–351. doi: 10.1111/j.1365-3083.2011.02516.x. Fulltekst i vitenarkiv
• Andersen, Jan Terje & Sandlie, Inger (2011). FcRn regulates the pharmacokinetics of albumin. Sojo University Publishing. Fulltekst i vitenarkiv

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