Variability of serum IgG sialylation and galactosylation degree in women with advanced endometriosis

Katarzyna Sołkiewicz,Ewa M Kratz,Hubert Krotkiewski,Marcin Jędryka

doi:10.1038/s41598-021-85200-x

Abstract

Endometriosis is an inflammatory disease which diagnostics is difficult and often invasive, therefore non-invasive diagnostics methods and parameters are needed for endometriosis detection. The aim of our study was to analyse the glycosylation of native serum IgG and IgG isolated from sera of women classified as: with endometriosis, without endometriosis but with some benign ginecological disease, and control group of healthy women, in context of its utility for differentiation of advanced endometriosis from the group of healthy women. IgG sialylation and galactosylation/agalactosylation degree was determined using specific lectins: MAA and SNA detecting sialic acid α2,3- and α2,6-linked, respectively, RCA-I and GSL-II specific to terminal Gal and terminal GlcNAc, respectively. The results of ROC and cluster analysis showed that the serum IgG MAA-reactivity, sialylation and agalactosylation factor may be used as supplementary parameters for endometriosis diagnostics and could be taken into account as a useful clinical tool to elucidate women with high risk of endometriosis development. Additionally, we have shown that the analysis of native serum IgG glycosylation, without the prior time-consuming and expensive isolation of the protein, is sufficient to differentiation endometriosis from a group of healthy women.

Highlights

Endometriosis, defined as the presence of endometrial glands and stroma like lesions outside of the u terus[1], has been diagnosed in 176 million women w orldwide[2]
Another important aspect was the comparison of native serum Immunoglobulin G (IgG) glycosylation with glycosylation of IgG isolated from serum, and evaluation the potential diagnostic suitability of glycan analysis when glycoprotein is not isolated earlier from biological fluid
Disease development is associated with inflammatory processes, especially in advanced stages of endometriosis, markers of which can be detected in peripheral blood serum

Summary

Introduction

Endometriosis, defined as the presence of endometrial glands and stroma like lesions outside of the u terus[1], has been diagnosed in 176 million women w orldwide[2]. Many reports described variations of IgG glycosylation, especially the degree of glycosylation, related to age, sex, heritability and pregnancy, as well as to autoimmune diseases and c ancers[24,25,26,27,28,29,30] It is already documented, that in rheumatoid arthritis patients, serum IgG galactosylation of its conservative N-glycans (Asn-297) in CH2 domains of the heavy chains is decreased, and that IgG agalactosylation is proportional to disease severity[31]. In the present study we were interested, if the expression of serum IgG sialylated and galactosylated/agalactosylated glycoforms is characteristic for advanced stages of endometriosis Another important aspect was the comparison of native serum IgG glycosylation with glycosylation of IgG isolated from serum, and evaluation the potential diagnostic suitability of glycan analysis when glycoprotein is not isolated earlier from biological fluid. The degree of IgG sialylation and galactosylation/agalactosylation was analysed using a modified solid phase enzyme-linked immunosorbent assay, lectin-ELISA31–34

Objectives

Methods

Results

Discussion

Conclusion