Inorganic Phosphate-Induced Extracellular Vesicles from Vascular Smooth Muscle Cells Contain Elevated Levels of Hyaluronic Acid, Which Enhance Their Interaction with Very Small Superparamagnetic Iron Oxide Particles.

Patients with chronic kidney disease (CKD) have a high prevalence of hyperphosphatemia, where uremic toxins like inorganic phosphate (Pi) induce a cardiovascular remodeling. Related disorders like atherosclerosis bear the risk of increased morbidity and mortality. We previously found that Pi stimulates the synthesis and sulfation of the negatively charged glycosaminoglycans (GAGs) heparan sulfate and chondroitin sulfate in vascular smooth muscle cells (VSMC). Similar GAG alterations were detected in VSMC-derived exosome-like extracellular vesicles (EV). These EV showed a strong interaction with very small superparamagnetic iron oxide particles (VSOP), which are used as imaging probes for experimental magnetic resonance imaging (MRI). Hyaluronic acid (HA) represents another negatively charged GAG which is supposed to function as binding motif for VSOP as well. We investigated the effects of Pi on the amounts of HA in cells and EV and studied the HA-dependent interaction between VSOP with cells and EV. Rat VSMC were treated with elevated concentrations of Pi. CKD in rats was induced by adenine feeding. EV were isolated from culture supernatants and rat plasma. We investigated the role of HA in binding VSOP to cells and EV via cell-binding studies, proton relaxometry, and analysis of cellular signaling, genes, proteins, and HA contents. Due to elevated HA contents, VSMC and EV showed an increased interaction with VSOP after Pi stimulation. Amongst others, Pi induced hyaluronan synthase (HAS)2 expression and activation of the Wnt pathway in VSMC. An alternative upregulation of HA by iloprost and an siRNA-mediated knockdown of HAS2 confirmed the importance of HA in cells and EV for VSOP binding. The in vitro-derived data were validated by analyses of plasma-derived EV from uremic rats. In conclusion, the inorganic uremic toxin Pi induces HA synthesis in cells and EV, which leads to an increased interaction with VSOP. HA might therefore be a potential molecular target structure for improved detection of pathologic tissue changes secondary to CKD like atherosclerosis or cardiomyopathy using EV, VSOP and MRI.

IgG Fc sialylation is regulated during the germinal center reaction following immunization with different adjuvants.

BACKGROUND: Effector functions of IgG Abs are regulated by their Fc N-glycosylation pattern. IgG Fc glycans that lack galactose and terminal sialic acid residues correlate with the severity of inflammatory (auto)immune disorders and have also been linked to protection against viral infection and discussed in the context of vaccine-induced protection. In contrast, sialylated IgG Abs have shown immunosuppressive effects. OBJECTIVE: We sought to investigate IgG glycosylation programming during the germinal center (GC) reaction following immunization of mice with a foreign protein antigen and different adjuvants. METHODS: Mice were analyzed for GC T-cell, B-cell, and plasma cell responses, as well as for antigen-specific serum IgG subclass titers and Fc glycosylation patterns. RESULTS: Different adjuvants induce distinct IgG+ GC B-cell responses with specific transcriptomes and expression levels of the α2,6-sialyltransferase responsible for IgG sialylation that correspond to distinct serum IgG Fc glycosylation patterns. Low IgG Fc sialylation programming in GC B cells was overall highly dependent on the Foxp3- follicular helper T (TFH) cell-inducing cytokine IL-6, here in particular induced by water-in-oil adjuvants and Mycobacterium tuberculosis. Furthermore, low IgG Fc sialylation programming was dependent on adjuvants that induced IL-27 receptor-dependent IFN-γ+ TFH1 cells, IL-6/IL-23-dependent IL-17A+ TFH17 cells, and high ratios of TFH cells to Foxp3+ follicular regulatory T cells. Here, the 2 latter were dependent on M tuberculosis and its cord factor. CONCLUSION: This study's findings regarding adjuvant-dependent GC responses and IgG glycosylation programming may aid in the development of novel vaccination strategies to induce IgG Abs with both high affinity and defined Fc glycosylation patterns in the GC.

N- and O-glycosylation patterns and functional testing of CGB7 versus CGB3/5/8 variants of the human chorionic gonadotropin (hCG) beta subunit.

The classical function of human chorionic gonadotropin (hCG) is its role in supporting pregnancy. hCG is a dimer consisting of two highly glycosylated subunits, alpha (CGA) and beta (CGB). The beta-hCG protein is encoded by CGB3, CGB5, CGB7 and CGB8 genes. CGB3, 5 and 8 code for an identical protein, CGB3/5/8, whereas CGB7 differs in three amino acids from CGB3/5/8. We had observed earlier that CGB7 and CGB3/5/8 display very distinct tissue expression patterns and that the tumor suppressor and transcription factor p53 can activate expression of CGB7 but not of CGB3/5/8 genes. Here, we investigate the glycan structures and possible functional differences of the two CGB variants. To this end, we established a system to produce and isolate recombinant CGA, CGB7 and CGB3/5/8 proteins. We found that N- and O-glycosylation patterns of CGB7 and CGB3/5/8 are quite similar. Functional assays were performed by testing activation of the ERK1/2 pathway and demonstrated that CGB7 and CGB5/5/8 appear to be functionally redundant isoforms, although a slight difference in the kinetics of ERK1/2 pathway activation was observed. This is the first time that biological activity of CGB7 is shown. In summary, the results lead to the hypothesis that CGB7 and CGB3/5/8 do not hold significant functional differences but that timing and cell type of their expression is the key for understanding their divergent evolution.

Systemic immune-checkpoint blockade with anti-PD1 antibodies does not alter cerebral amyloid-ß burden in several amyloid transgenic mouse models.

Chronic inflammation represents a central component in the pathogenesis of Alzheimer's disease (AD). Recent work suggests that breaking immune tolerance by Programmed cell Death-1 (PD1) checkpoint inhibition produces an IFN-γ-dependent systemic immune response, with infiltration of the brain by peripheral myeloid cells and neuropathological as well as functional improvements even in mice with advanced amyloid pathology (Baruch et al., (): Nature Medicine, 22:135-137). Immune checkpoint inhibition was therefore suggested as potential treatment for neurodegenerative disorders when activation of the immune system is appropriate. Because a xenogeneic rat antibody (mAb) was used in the study, whether the effect was specific to PD1 target engagement was uncertain. In the present study we examined whether PD1 immunotherapy can lower amyloid-ß pathology in a range of different amyloid transgenic models performed at three pharmaceutical companies with the exact same anti-PD1 isotype and two mouse chimeric variants. Although PD1 immunotherapy stimulated systemic activation of the peripheral immune system, monocyte-derived macrophage infiltration into the brain was not detected, and progression of brain amyloid pathology was not altered. Similar negative results of the effect of PD1 immunotherapy on amyloid brain pathology were obtained in two additional models in two separate institutions. These results show that inhibition of PD1 checkpoint signaling by itself is not sufficient to reduce amyloid pathology and that additional factors might have contributed to previously published results (Baruch et al., (): Nature Medicine, 22:135-137). Until such factors are elucidated, animal model data do not support further evaluation of PD1 checkpoint inhibition as a therapeutic modality for Alzheimer's disease.

The Cell-Surface N-Glycome of Human Embryonic Stem Cells and Differentiated Hepatic Cells thereof.

Human embryonic stem cells (hESCs) are pluripotent stem cells that offer a wide range of applications in regenerative medicine. In addition, they have been proposed as an appropriate alternative source of hepatocytes. In this work, hESCs were differentiated into definitive endodermal cells (DECs), followed by maturation into hepatocyte-like cells (HLCs). Their cell-surface N-glycome was profiled and also compared with that of primary human hepatocytes (PHHs). Undifferentiated hESCs contained large amounts of high-mannose N-glycans. In contrast, complex-type N-glycans such as asialylated or monosialylated biantennary and triantennary N-glycans were dominant in HLCs, and fully galactosylated structures were significantly more abundant than in undifferentiated hESCs. The cell-surface N-glycosylation of PHHs was more biologically processed than that of HLCs, with bisialylated biantennary and trisialylated triantennary structures predominant. This is the first report of the cell surface N-glycome of PHHs and of HLCs being directly generated from hESCs without embryoid body formation.

Genetic Versus Epigenetic BRCA1 Silencing Pathways: Clinical Effects in Primary Ovarian Cancer Patients: A Study of the Tumor Bank Ovarian Cancer Consortium.

OBJECTIVES: The aim of the present study was to assess in a large cohort of primary epithelial ovarian cancer patients the incidence and the clinical effect of BRCA1 genetic and epigenetic silencing mechanisms. METHODS: A total of 188 primary epithelial ovarian cancer patients, treated between 2000 and 2011 at the Charité University Hospital of Berlin, were included. The patients' tumor and blood samples were obtained from the Tumor Bank Ovarian Cancer Network (www.toc-network.de). Direct sequencing of BRCA1 exon 11 was performed to detect germline mutations, whereas tumor samples were assessed for BRCA1 promoter hypermethylation by bisulphite-converted methylation-specific polymerase chain reaction. Basing on their BRCA1 status, patients were compared regarding clinicopathological variables and survival. RESULTS: Twenty-one patients (11.2%) showed hypermethylation in BRCA1 promoter (HMB), and 18 patients (9.6%) presented germline mutations in BRCA1 exon 11 (GMB). Patients with HMB showed a significantly younger age at diagnosis compared with BRCA1 wild type (BWT) patients (54 vs 61 years, P = 0.045), and both GMB and HMB patients were more likely to have high-grade serous ovarian cancer (76.2% and 77.8% vs 52.7%, P = 0.043 and P = 0.043). Positive family history of breast or ovarian cancer (OC) was more frequently reported among GMB patients with respect to BWT patients (44.4% vs 13.5%, P = 0.003); GMB, HMB, and BWT patients did not show significant differences in terms of tumor dissemination pattern, surgical outcomes, platinum response or survival; neither mutational nor hypermethylation BRCA1 status was found to be an independent prognostic factor for OC patients. CONCLUSIONS: Hypermethylation in BRCA1 is associated with earlier occurrence of OC. In addition, the coexistence of both GBM and HMB is an infrequent event, occurring in 0.5% of OC cases. Silencing of BRCA1 through mutation and hypermethylation confers to distinct clinical characteristics of OC patients but similar clinical outcome with respect to BWT patients.

Acute-phase glycoprotein N-glycome of ovarian cancer patients analyzed by CE-LIF.

Epithelial ovarian cancer (EOC) is the most frequent cause of death from all gynecological malignancies because of its late diagnosis. As N-glycosylation is modified in the course of ovarian cancer, it is a promising source of tumor biomarkers. In this work, serum glycoproteins, depleted from albumin and IgG, were separated by 2DE. Protein spots of acute-phase proteins were identified by peptide mapping and their corresponding glycan moieties were released enzymatically, fluorescently labeled and analyzed by CE-LIF. In the positive acute-phase proteins, haptoglobin, α1-antitrypsin, and α1-antichymotrypsin, an increase of antennarity and Lewis(X) motif could be measured in EOC patients on tri- and/or tetraantennary N-glycans. Tetraantennary N-glycans containing three Lewis(X) epitopes and triantennary N-glycans containing a ß(1-6) branch and a Lewis(X) epitope were only present in EOC patients. We also showed for the first time that the core-fucosylated biantennary digalactosylated N-glycan of α1-acid glycoprotein is a potential biomarker for EOC. To conclude, core-fucosylated biantennary N-glycans on α1-acid glycoprotein as well as higher antennarity and increased amounts of Lewis(X) motif on haptoglobin, α1-antitrypsin, and α1-antichymotrypsin are promising biomarkers for EOC. Nevertheless, their specificity and selectivity for the early detection of EOC should be evaluated in a larger study.

Enhanced detection of in-gel released N-glycans by MALDI-TOF-MS.

Many biologically relevant glycoproteins need to be separated on 1D- or 2D-gels prior to analysis and are available in picomole amounts. Therefore, it is important to have optimized methods to unravel the glycome that combine in-gel digestions with MALDI-TOF-MS. In this technical report, we investigated how the detection of in-gel released N-glycans could be improved by MALDI-TOF-MS. First, an AnchorChip target was tested and compared to ground steel target using several reference oligosaccharides. The highest signals were obtained with an AnchorChip target and D-arabinosazone as the matrix; a LOD of 1.3 to 10 fmol was attained. Then, the effect of octyl-ß-glucopyranoside, a nonionic detergent, was studied during in-gel peptide-N(4) -(acetyl-ß-glucosaminyl) asparagine amidase F digestion of standard glycoproteins and during glycan extraction. Octyl-ß-glucopyranoside increased the intensity and the amount of detected neutral as well as acidic N-glycans. A LOD of under 7 pmol glycoprotein could be achieved.

The human rhabdomyosarcoma cell line TE671--Towards an innovative production platform for glycosylated biopharmaceuticals.

The market of therapeutic glycoproteins (including coagulation factors, antibodies, cytokines and hormones) is one of the profitable, fast-growing and challenging sectors of the biopharmaceutical industry. Although mammalian cell culture is still expensive and technically complex, the ability to produce desired post-translational modifications, in particular glycosylation, is a major issue. Glycans can influence ligand binding, serum half-life as well as biological activity or product immunogenicity. Aiming to establish a novel production platform for recombinant glycoproteins, the human TE671 cell line was investigated. Since the initial analysis of cell membrane proteins showed a promising glycosylation of TE671 cells for biotechnological purposes, we focused on the recombinant expression of two model glycoproteins of therapeutical relevance. The optimization of the cell transfection procedure and serum-free expression succeeded for the human serine protease inhibitor alpha-1-antitrypsin (A1AT) and the hematopoietic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF). N-glycan analyses of both purified proteins by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry provided first fundamental insights into the TE671 glycosylation potential. Besides protein specific pattern, strong distinctions - in particular for N-glycan fucosylation and sialylation - were observed depending on the medium conditions of the respective TE671 cell cultivations. The cell line's ability to synthesize complex and highly sialylated N-glycan structures has been shown. Our results demonstrate the TE671 cell line as a serious alternative to other existing human expression systems.

Rapid analysis of cell surface N-glycosylation from living cells using mass spectrometry.

Cell surfaces are covered with a dense carbohydrate layer referred to as the glycocalyx. Because different cell types express different glycan signatures, it is of paramount importance to have robust methods to analyze the glycome of living cells. To achieve this, a common procedure involves cell lysis and extraction of membrane (glyco)proteins and yields a major proportion of high-mannose N-glycans that most likely stem from intracellular proteins derived from the ER. Using HEK 293 cells as a model system, we developed a reproducible, sensitive, and fast method to profile surface N-glycosylation from living cells. We directly released glycopeptides from cell surfaces through tryptic digestion of freshly harvested and vital cells, thereby improving the detection and quantification of complex-type N-glycans by increasing their relative amount from 14 to 85%. It was also possible to detect 25 additional structures in HEK 293, 48 in AGE1.HN, 42 in CHO-K1, and 51 in Hep G2 cells. The additional signals provided deeper insight into cell-type-specific N-glycan features such as antennarity, fucosylation, and sialylation. Thus, this protocol, which can potentially be applied to any cells, will be useful in the fields of glycobiotechnology and biomarker discovery.

Sialic acid methylation refines capillary electrophoresis laser-induced fluorescence analyses of immunoglobulin G N-glycans of ovarian cancer patients.

Alterations in IgG N-glycosylation coincide with the development of a number of diseases including cancer and could potentially be used as diagnostic markers. CE-LIF of 8-aminopyrene-1,3,6-trisulfonic acid labeled N-glycans is a well-established rapid method to characterize IgG N-glycans that needs only low amounts of starting material. However,sialylated N-glycans have short migration times due to their negative charge. As a result,some of them are not well resolved and co-migrate with neutral glycans. In this work, we neutralized the negative charge of sialic acids by methylation and optimized the protocol using the commercially available disialylated biantennary oligosaccharide (A2G2S2). IgGN-glycans isolated from healthy human serum were then analyzed using this method. We could demonstrate that co-migration of A2, FA2G2S1, and FA2B[3]G1S1 was prevented,which allowed an accurate quantification of these N-glycans. Finally, we investigated the IgG N-glycan profiles of patients suffering from ovarian cancer using the conventional and methylation methods.With both methods, we observed an increase of agalactosylated structures that was accompanied by a decrease in digalactosylated structures. Finally, using the methylation protocol, we could further demonstrate an increase of A2, which was technically impossible with the conventional method.

Identification of 34 N-glycan isomers in human serum by capillary electrophoresis coupled with laser-induced fluorescence allows improving glycan biomarker discovery.

Alterations in glycosylation have been observed in many human diseases and specific changes in glycosylation have been proposed as relevant diagnostic information. Capillary electrophoresis coupled with laser-induced fluorescence (CE-LIF) is a robust method to quantify desialylated N-glycans that are labeled with 8-aminopyrene-1,3,6-trisulfonic acid prior to analysis. To date, only a maximum of 12 glycan structures, the most abundant ones, have been identified by CE-LIF to characterize glycome modulations of total serum in the course of the diseases. In most forms of cancer, findings using CE-LIF were limited to the increase of triantennary structures carrying a Lewis(x) epitope. In this work, we identified 32 linkage and positional glycan isomers in healthy human serum using exoglycosidase digestions as well as standard glycoproteins, for which we report the assignment of novel structures. It was possible to identify and quantify 34 glycan isomers in the serum of primary epithelial ovarian cancer patients (EOC). Reduced levels of diantennary structures and of high-mannose 5 were statistically significant in the EOC samples, and also, elevated branching as well as increased antennary fucosylation were observed. For the first time, we could demonstrate that not only antennary fucosylation was of relevance in tetraantennary structures but also core-fucosylated tetraantennary N-glycans were statistically increased in EOC patients. The results of the current study provide an improved dataset to be used in glycan biomarker discovery.

Impact of educational workshops to increase awareness of pelvic floor dysfunction and integrate preventive lifestyle habits.

OBJECTIVES: Our objectives were to evaluate the impact of group pelvic floor education workshops on participants' knowledge, their satisfaction, and the modification of their urinary and digestive behaviors, and to compare health care providers' (HCP) knowledge with that of the general population. METHODS: For this prospective observational study, group pelvic floor education workshops were proposed between May 2021 and June 2022 in a web-conference format. Each workshop covered pelvic floor anatomy and physiology, urinary and digestive physiology as well as risk factors of PFD and preventive measures. At the start and the end of the workshops, participants completed a questionnaire on their knowledge and their beliefs about the pelvic floor. Questions about their satisfaction were asked at the end of the workshops. A 2-month questionnaire assessed changes in urinary and digestive habits and whether participants had talked about the workshop around them. RESULTS: A total of 856, with an average age 40.1 years, participated and completed the questionnaires before and after the workshops; 694 responded at 2 months. The education workshops significantly improved knowledge about the pelvic floor in the "HCP" and "non-HCP" groups. At 2 months, 591 participants (85.2%) 85.2% had talked about the workshop content; 557 (80.3%) reported having changed, or planned to change, their urinary behaviors and 495 (71.3%) their defecatory behaviors. CONCLUSIONS: Pelvic floor education workshops can increase level of knowledge and thus limit risky behaviors for the pelvic floor. The high rate of participation and the satisfaction of the participants shows the interest for the theme.

The Cerebrospinal Fluid Free-Glycans Hex1 and HexNAc1Hex1Neu5Ac1 as Potential Biomarkers of Alzheimer's Disease.

Alzheimer's disease (AD) is the most common neurodegenerative disorder, affecting a growing number of elderly people. In order to improve the early and differential diagnosis of AD, better biomarkers are needed. Glycosylation is a protein post-translational modification that is modulated in the course of many diseases, including neurodegeneration. Aiming to improve AD diagnosis and differential diagnosis through glycan analytics methods, we report the glycoprotein glycome of cerebrospinal fluid (CSF) isolated from a total study cohort of 262 subjects. The study cohort consisted of patients with AD, healthy controls and patients suffering from other types of dementia. CSF free-glycans were also isolated and analyzed in this study, and the results reported for the first time the presence of 19 free glycans in this body fluid. The free-glycans consisted of complete or truncated N-/O-glycans as well as free monosaccharides. The free-glycans Hex1 and HexNAc1Hex1Neu5Ac1 were able to discriminate AD from controls and from patients suffering from other types of dementia. Regarding CSF N-glycosylation, high proportions of high-mannose, biantennary bisecting core-fucosylated N-glycans were found, whereby only about 20% of the N-glycans were sialylated. O-Glycans and free-glycan fragments were less sialylated in AD patients than in controls. To conclude, this comprehensive study revealed for the first time the biomarker potential of free glycans for the differential diagnosis of AD.

Consequences of GMPPB deficiency for neuromuscular development and maintenance.

Guanosine diphosphate-mannose pyrophosphorylase B (GMPPB) catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, which is required as a mannose donor for the biosynthesis of glycan structures necessary for proper cellular functions. Mutations in GMPPB have been associated with various neuromuscular disorders such as muscular dystrophy and myasthenic syndromes. Here, we report that GMPPB protein abundance increases during brain and skeletal muscle development, which is accompanied by an increase in overall protein mannosylation. To model the human disorder in mice, we generated heterozygous GMPPB KO mice using CIRSPR/Cas9. While we were able to obtain homozygous KO mice from heterozygous matings at the blastocyst stage, homozygous KO embryos were absent beyond embryonic day E8.5, suggesting that the homozygous loss of GMPPB results in early embryonic lethality. Since patients with GMPPB loss-of-function manifest with neuromuscular disorders, we investigated the role of GMPPB in vitro. Thereby, we found that the siRNA-mediated knockdown of Gmppb in either primary myoblasts or the myoblast cell line C2C12 impaired myoblast differentiation and resulted in myotube degeneration. siRNA-mediated knockdown of Gmppb also impaired the neuron-like differentiation of N2A cells. Taken together, our data highlight the essential role of GMPPB during development and differentiation, especially in myogenic and neuronal cell types.

Oxonium ion scanning mass spectrometry for large-scale plasma glycoproteomics.

Protein glycosylation, a complex and heterogeneous post-translational modification that is frequently dysregulated in disease, has been difficult to analyse at scale. Here we report a data-independent acquisition technique for the large-scale mass-spectrometric quantification of glycopeptides in plasma samples. The technique, which we named 'OxoScan-MS', identifies oxonium ions as glycopeptide fragments and exploits a sliding-quadrupole dimension to generate comprehensive and untargeted oxonium ion maps of precursor masses assigned to fragment ions from non-enriched plasma samples. By applying OxoScan-MS to quantify 1,002 glycopeptide features in the plasma glycoproteomes from patients with COVID-19 and healthy controls, we found that severe COVID-19 induces differential glycosylation in IgA, haptoglobin, transferrin and other disease-relevant plasma glycoproteins. OxoScan-MS may allow for the quantitative mapping of glycoproteomes at the scale of hundreds to thousands of samples.

Serum glycome profiling: a biomarker for diagnosis of ovarian cancer.

During the development of cancer, changes in cellular glycosylation are observed, indicating that alterations of the glycome occur in extracellular fluids as well as in serum and could therefore serve as tumor biomarkers. In the case of epithelial ovarian cancer (EOC), common tumor markers such as CA125 are known to have poor specificity; therefore, better biomarkers are needed. The aim of this work was to identify new potential glycan biomarkers in EOC-patients. N-Glycans were cleaved from serum glycoproteins from 63 preoperative primary EOC-patients along with 33 age-matched healthy women, permethylated, and analyzed using MALDI-TOF mass spectrometry. A value named GLYCOV was calculated from the relative areas of the 11 N-glycan biomarkers revealed by SPSS statistical analyses, namely four high-mannose and seven complex-type fucosylated N-glycans. GLYCOV diagnosed primary EOC with a sensitivity of 97% and a specificity of 98.4% whereas CA-125 showed a sensitivity of 97% and a specificity of 88.9%. Our study is the first one to compare glycan values with the established tumor marker CA125 and to give better results. Therefore, the N-glycome could potentially be used as a biomarker.

Endo-ß-N-acetylglucosaminidase H de-N-glycosylation in a domestic microwave oven: application to biomarker discovery.

Sample preparation is the rate-limiting step in glycan analysis workflows. Among all of the steps, enzymatic digestions, which are usually performed overnight, are the most time-consuming. In the current study, we report an economical and fast preparation of N-glycans from serum, including microwave-assisted enzymatic digestion in the absence of denaturing chemicals and solvents during the release. To this end, we used a household microwave oven to accelerate both pronase and endo-ß-N-acetylglucosaminidase H (Endo H) digestions. Purification was then performed using self-made SP20SS and carbon tips. We were able to prepare samples in 55 min instead of 21 h. Finally, the method was applied in the context of oncological biomarker discovery exemplarily to ovarian and colon cancer. We observed a significant downregulation of sialylated hybrid structures in ovarian cancer samples using capillary electrophoresis-laser-induced fluorescence (CE-LIF). Furthermore, sepsis, a systemic inflammatory response syndrome, was also included in the study to understand whether the changes observed in ovarian cancer patients were due to the cancer itself or to the inflammation that usually accompanies its development. Because sialylated hybrid structures were upregulated in sepsis samples, the downregulation of these structures in ovarian cancer is specific to the cancer itself and, therefore, could be used as a biomarker.