Mannose-binding Lectin in Pregnancy Course and Outcome: Studies in healthy women and rheumatoid arthritis patients

Pregnancy is considered an immunological phenomenon since the pregnant mother needs to accommodate the fetal allograft. This requires profound changes of the maternal immune system. In this scope it has been hypothesized that the improvement of autoimmune diseases like rheumatoid arthritis (RA) is a result of adaptations of the immune system during pregnancy. The mechanism underlying this phenomenon and factors that can predict improvement or deterioration of RA are still largely unknown, but multiple hypotheses have been proposed 1-9. It has been suggested that the adaptive immunity declines during pregnancy, enabling the pregnant body to tolerate the fetus as a semi-allograft. As a consequence, it can be hypothesized that innate immunity compensates during this state of reduce

Immunoglobulin G galactosylation and sialylation are associated with pregnancy-induced improvement of rheumatoid arthritis and the postpartum flare: Results from a large prospective cohort study

Introduction: Improvement of rheumatoid arthritis (RA) during pregnancy has been causatively associated with increased galactosylation of immunoglobulin G (IgG) N-glycans. Since previous studies were small, did not include the postpartum flare and did not study sialylation, these issues were addressed in the present study.Methods: Serum from 148 RA cases and 32 healthy controls was collected at several time points before, during and after pregnancy. Improvement during pregnancy and postpartum flare were determined according to the European League Against Rheumatism (EULAR) response criteria. Galactosylation and sialylation of Immunoglobulin G (IgG) and the presence of bisecting N-acetylglucosamine (GlcNAc) were analyzed by matrix-assisted laser desorption/ionization - time of flight - mass spectrometry (MALDI-TOF-MS).Results: IgG1 and IgG2 galactosylation of the cases and controls increased during pregnancy with a maximum in the third trimester. Galactosylation decreased directly postpartum. IgG galactosylation of controls was at a higher level than cases (P < 0.001 at all time points) and a similar pattern was observed for sialylation. Moreover, there was a good association between galactosylation and sialylation. The increase in galactosylation was significantly more pronounced for cases with improvement than cases without improvement during pregnancy. The reverse was true for deteriorators and non-deteriorators postpartum. The presence of bisecting GlcNAc was not significantly influenced by pregnancy or postpartum for c

Mannose-binding lectin levels during pregnancy: A longitudinal study

Background: Pregnancy is associated with changes in the immune system. Although previous studies have focussed mainly on adaptive immunity, there are indications that components of innate immunity, such as mannose-binding lectin (MBL), are associated with pregnancy outcome. Although this would suggest that pregnancy also involves adaptations in innate immunity, there are few studies in this area. Therefore, we aimed to determine whether MBL concentrations and the following steps in complement pathway activation are influenced by pregnancy. Methods: MBL and Ficolin-2 concentrations, MBL-MBL-associated serine protease (MASP) complex activity, MBL pathway activity and classical complement pathway activity were determined by enzyme-linked immunosorbent assay (ELISA) in sera from pregnant women (n = 32) during each trimester and post-partum. MBL genotyping was performed by PCR. Results: During pregnancy, MBL concentrations increased to 140% [interquartile range (IQR) 116-181%, P < 0.0001]. This increase was already present at 12 weeks of pregnancy and was most pronounced in the high-production AA-gen