Kristina Sæterdal Kømurcu

• Kømurcu, Kristina Sæterdal; Zawadzka, Malgorzata Elzbieta; Meszka, Igor; Aizenshtadt, Aleksandra; Hrušková, Helena & Aakervik, Lydia Emilie [Show all 10 contributors for this article] (2026). A Validated Mass Spectrometry Platform for Oxysterol Analysis of Single Human Gastruloids and Liver Organoids. Analytical Chemistry. ISSN 0003-2700. 98(9), p. 6792–6804. doi: 10.1021/acs.analchem.5c07140. Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2024). LC-MS Approaches for Oxysterols in Various Biosamples. Advances in Experimental Medicine and Biology. ISSN 0065-2598. 1440, p. 57–71. doi: 10.1007/978-3-031-43883-7_4. Full text in Research Archive Show summary

  Oxysterols are involved in a plethora of biological processes, including a wide variety of diseases. Therefore, monitoring oxysterols is important for obtaining a deeper understanding of their biological roles and utilizing them as, for example, biomarkers. However, oxysterols can be challenging compounds to study, as they can be very similar in chemical structure but still have distinct biological roles. In addition, oxysterols may be difficult to detect, even with advanced analytical instrumentation. We here focus on the use of liquid chromatography–mass spectrometry (LC–MS) for the analysis of oxysterols, with an additional focus on the steps needed to prepare oxysterols for LC–MS. Steps can include chemical modification of the oxysterols for improving LC–MS sensitivity and adding chemicals that can reveal if the oxysterol levels have been perturbed during preparation. We then round off with descriptions and applications of various sample preparations for different biological matrices, from blood to cells, and biosamples with emerging attention, for example, exosomes and organoids. Taken together, oxysterol analysis is highly compatible with a wide variety of biosamples, allowing for a deeper understanding of these challenging analytes.

• Kømurcu, Kristina Sæterdal; Wilhelmsen, Ingrid; Thorne, James L.; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Aizenshtadt, Aleksandra [Show all 7 contributors for this article] (2023). Mass spectrometry reveals that oxysterols are secreted from non-alcoholic fatty liver disease induced organoids. Journal of Steroid Biochemistry and Molecular Biology. ISSN 0960-0760. 232. doi: 10.1016/j.jsbmb.2023.106355. Full text in Research Archive Show summary

  Oxysterols are potential biomarkers for liver metabolism that are altered under disease conditions such as non-alcoholic fatty liver disease (NAFLD). We here apply sterolomics to organoids used for disease modeling of NAFLD. Using liquid chromatography-mass spectrometry with on-line sample clean-up and enrichment, we establish that liver organoids produce and secrete oxysterols. We find elevated levels of 26-hydroxycholesterol, an LXR agonist and the first oxysterol in the acidic bile acid synthesis, in medium from steatotic liver organoids compared to untreated organoids. Other upregulated sterols in medium from steatotic liver organoids are dihydroxycholesterols, such as 7α,26–dihydroxycholesterol, and 7α,25-dihydroxycholesterol. Through 26-hydroxycholesterol exposure to human stem cell-derived hepatic stellate cells, we observe a trend of expressional downregulation of the pro-inflammatory cytokine CCL2, suggesting a protective role of 26-hydroxycholesterol during early-phased NAFLD disease development. Our findings support the possibility of oxysterols serving as NAFLD indicators, demonstrating the usefulness of combining organoids and mass spectrometry for disease modeling and biomarker studies.

• Kogler, Stian; Kømurcu, Kristina Sæterdal; Olsen, Christine Sandsnes; Shoji, Jun-ya; Skottvoll, Frøydis Sved & Krauss, Stefan Johannes Karl [Show all 8 contributors for this article] (2023). Organoids, organ-on-a-chip, separation science and mass spectrometry: An update. TrAC. Trends in analytical chemistry. ISSN 0165-9936. 161. doi: 10.1016/j.trac.2023.116996. Full text in Research Archive Show summary

  Organoids are 3D models of organs, grown in the laboratory from stem cells. An organ model grown/placed in microfluidic devices is commonly termed an “organ-on-a-chip”. Organoids and organ-on-a-chip devices are becoming important tools for studying physiology, disease modeling, drug discovery, personalized medicine, toxicology, and organ development/embryogenesis. We review how mass spectrometry is used for studying organoids and organ-on-a-chip-derived material. We first focus on proteomics, metabolomics/lipidomics, and hormones, typically discussing liquid chromatography-mass spectrometry (LC-MS) approaches. We then review work on mass spectrometry imaging (MSI) of organoids and discuss organ-on-a-chip coupled with mass spectrometry. The review focuses on research developments from the past four years. Mass spectrometric analysis of organoids and organ-on-a-chip has allowed novel insights on development and disease of e.g. brain, liver, and tumors, demonstrating potential for replacing or complementing animal models and other traditional model systems. Additional applications are emerging, e.g. related to sports doping and environmental toxicology.

• Røberg-Larsen, Hanne; Lund, Kaja; Sæterdal, Kristina Erikstad; Solheim, Stian; Vehus, Tore & Solberg, Nina [Show all 9 contributors for this article] (2017). Mass spectrometric detection of 27-hydroxycholesterol in breast cancer exosomes. Journal of Steroid Biochemistry and Molecular Biology. ISSN 0960-0760. 169, p. 22–28. doi: 10.1016/j.jsbmb.2016.02.006. Full text in Research Archive
• Berg, Henriette Sjånes; Sæterdal, Kristina Erikstad; Smetop, Tone; Rozenvalds, Rūdolfs; Brandtzaeg, Ole Kristian & Vehus, Tore [Show all 8 contributors for this article] (2017). Self-packed core shell nano liquid chromatography columns and silica-based monolithic trap columns for targeted proteomics. Journal of Chromatography A. ISSN 0021-9673. 1498, p. 111–119. doi: 10.1016/j.chroma.2017.03.043. Full text in Research Archive
• Vehus, Tore; Sæterdal, Kristina Erikstad; Krauss, Stefan; Lundanes, Elsa & Wilson, Steven Ray Haakon (2016). Comparison of commercial nanoliquid chromatography columns for fast, targeted mass spectrometry-based proteomics. Future science OA. 2(2). doi: 10.4155/fsoa-2016-0014. Full text in Research Archive

View all works in NVA

• Røberg-Larsen, Hanne; Kømurcu, Kristina Sæterdal; Kogler, Stian; Olsen, Christine; Skottvoll, Frøydis Sved & Aizenshtadt, Aleksandra [Show all 8 contributors for this article] (2023). Organoids, Organ-on-a-chip and Mass Spectrometry. Full text in Research Archive
• Midtøy, Lise; Kømurcu, Kristina Sæterdal; Kogler, Stian; wilhelmsen, ingrid; Røberg-Larsen, Hanne & Wilson, Steven Ray Haakon (2023). Sensitive targeted proteomic analysis of cholesterol metabolism enzymes in hepatic stellate cells - going towards single cell analysis. Full text in Research Archive
• kvalvik, Eva; Kogler, Stian; Kømurcu, Kristina Sæterdal; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2023). Screening for biomarkers for non-alcoholic fatty liver disease using organ-in-a-column technology. Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Aizenshtadt, Aleksandra; Thorne, James L; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2022). Oxysterols are secreted from Non-alcoholic Fatty Liver disease induced organoids. Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Aizenshtadt, Aleksandra; Thorne, James L; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2022). Measuring oxysterols using LC-MS for the understanding of non alcoholic fatty liver disease (NAFLD). Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Aizenshtadt, Aleksandra; Thorne, James L; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2022). Measuring oxysterols secreted from liver organoids by LC-MS for the understanding of Non-alcoholic fatty liver disease. Full text in Research Archive
• midtøy, Lise; Kømurcu, Kristina Sæterdal; Kogler, Stian; wilhelmsen, Ingrid; Røberg-Larsen, Hanne & Wilson, Steven Ray Haakon (2022). Sensitive targeted proteomic analysis of cholesterol metabolism enzymes in hepatic stellate cells - going towards single cell analysis. Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Aizenshtadt, Aleksandra; Thorne, James L.; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2022). Oxysterols are secreted from Non-Alcoholic Fatty Liver Disease (NAFLD) induced organoids. Full text in Research Archive
• Kømurcu, Kristina Sæterdal; Aizenshtadt, Aleksandra; Thorne, James L; Krauss, Stefan Johannes Karl; Wilson, Steven Ray Haakon & Røberg-Larsen, Hanne (2022). Measuring oxysterols secreted from liver organoids by LC-MS for the understanding of Non-alcoholic fatty liver disease. Full text in Research Archive
• Berg, Henriette Sjånes; Bjørseth, Kamilla; Sæterdal, Kristina Erikstad; Smetop, Tone; Skottvoll, Frøydis Sved & Vehus, Tore [Show all 8 contributors for this article] (2018). Evaluation of isolation methods of glioma exosomes for biomarker discovery. Full text in Research Archive Show summary

  Gliomas are the most common form of brain cancer, where the sub-group glioblastoma multiforme (GBM) is the most aggressive and the most common in adults [1]. For diagnostic, prognostic, and treatment monitoring, fast and reliable analytical methods for detection of glioblastoma tumors are essential. Non-invasive monitoring of circulating biomarkers in blood (liquid biopsy) is a desirable possibility [2]. Nano LC-MS can provide the high sensitivity, selectivity and low false positive rate needed for the proteomic analysis of exosomes, which are extracellular vesicles released from the tumor and into the bloodstream. We have optimized the packing of 50 µm capillaries (2.6 µm C18 core-shell particles) with peak capacities comparable to similar commercial nano-LC columns (75 µm ID) for peptide separations of minute samples (e.g. exosomes). These columns have previously been successfully used for the targeted detection of CYP27a (a potential breast cancer biomarker) in the MDA-MB-231 cell line. In the present study, these in-house packed columns have been applied for proteins in exosomes isolated from GBM cell culture medium. The aim of this study was to compare isolation methods of GMB exosomes for biomarker discovery and study proteins related to GBM in exosomes. Ultracentrifugation (“golden standard” in exosome isolation) was compared to a Total Exosome Isolation Reagent from Invitrogen (Thermo Fisher Scientific) regarding sample volume, total protein amount, purity, and the presence of exosome markers and GBM biomarker candidates. References 1. Molina, J.R., Y. Hayashi, C. Stephens, and M.M. Georgescu, Invasive Glioblastoma Cells Acquire Stemness and Increased Akt Activation. Neoplasia. 12 (2010) 453-U37. 2. Best, M.G., N. Sol, S. Zijl, J.C. Reijneveld, P. Wesseling, and T. Wurdinger, Liquid biopsies in patients with diffuse glioma. Acta Neuropathologica. 129 (2015) 849-865.

• Berg, Henriette Engen; Skottvoll, Frøydis Sved; Bjørseth, Kamilla; Sæterdal, Kristina Erikstad; Brandtzaeg, Ole Kristian & Vehus, Tore [Show all 11 contributors for this article] (2018). Development of nanoLC column technology for proteomic studies. Full text in Research Archive Show summary

  Background NanoLC has emerged as a major technique in proteomics due to improved sensitivity, which enables analysis of small sample volumes and low concentrations. In our group (Bioanalytical chemistry, BACH) we focus on the development of column technology, including porous layer open tubular (PLOT) columns and self-packing of columns for proteomic applications. Methods The PLOT columns were used for both on-line digestion (enzyme reactors) and separations (10 µm ID, PS-DVB with ODS). Enzyme reactors (20 µm ID and multi-PLOT columns (~8 µm ID)) were immobilized with trypsin and Lys-C for protein digestion. We also compared self-packed columns of 50 µm ID (2.6 µm C18 core-shell particles) to a commercial column (75 µm ID). The columns were used for detection of CYP27a1 in MDA-MB-231 (breast cancer) cells, and biomarker candidates in MDA-MB-231 and glioblastoma multiforme (brain cancer) exosomes. For exosome isolation (cell culture medium), ultracentrifugation (“golden standard”) was compared to a Total Exosome Isolation Reagent from Thermo Fisher regarding protein yield and purity. Results Our PLOT columns were successfully employed for proteins, metabolites and peptides with attogram detection limits and peak capacities around 250 [1]. The enzyme reactors provided sufficient digestion in ~5 minutes compared to overnight digestions (common in off-line protocols) [2]. Furthermore, a quantitative method of the neurotoxin ricin was developed using the multi-PLOT to reduce manual sample handling [3] . The self-packed columns obtained peak capacities comparable to the commercial nanoLC column for peptide separations [4]. The self-packed columns were used for the targeted detection of CYP27A1 (potential breast cancer biomarker) in MDA-MB-231 cells. In the recent exosome study, exosomes were present and biomarker candidates were identified. However, the characterization techniques are in our hands not satisfactory. Conclusions We have successfully developed sensitive nanoLC column formats for proteomic applications.

• Røberg-Larsen, Hanne; Lund, Kaja; Sæterdal, Kristina Erikstad; Solheim, Stian; Vehus, Tore & Solberg, Nina [Show all 9 contributors for this article] (2016). Capillary LC mass spectrometric detection of 27-hydroxycholesterol in breast cancer exosomes. Full text in Research Archive
• Sæterdal, Kristina Erikstad; Vehus, Tore; Røberg-Larsen, Hanne; Krauss, Stefan; Lundanes, Elsa & Wilson, Steven Ray Haakon (2016). Determination of CYP27a1 in biological samples using nano liquid chromatography mass spectrometry. Universitetet i Oslo. Full text in Research Archive Show summary

  The cytochrome P450 enzyme, CYP27a1, converts cholesterol into 27-hydroxycholesterol, and both the metabolite and the enzyme are associated with breast cancer, promoting proliferation and metastasis. CYP27A1 is enriched in cancer tissues, and the amount of CYP27a1 correlates to tumor grade. Hence, CYP27a1 is a potential biomarker, and a method for determination and quantification is needed. Antibody assays shows limited performance, and therefore the goal of this work was to develop a nano liquid chromatography mass spectrometry (LC-MS) method for determination of CYP27a1. A sample preparation workflow for CYP27a1 in cell samples was investigated. CYP27a1 was identified by nano LC-MS in MDA-MB-231 breast cancer cells by fractionating cell lysates using gel electrophoresis. Enrichment of CYP27a1 in cell samples using immunoprecipitation, an antibody based method for protein extraction, did not provide adequate identification. However the former method works when looking at other proteins, and this confirms that there are limitations in using antibody based methods for determination and quantification of CYP27a1.

View all works in NVA