Lectin-based analysis of fucose and sialic acid expressions on human amniotic IgA during normal pregnancy

Abstract

The sugar moiety of IgA is known to provide a link between the innate and adaptive immune systems. Terminally located glycotopes on IgA are potential ligands engaged in the interactions which may modulate the biological activities of IgA. In the present work the expressions of Maackia amurensis (MAA), Sambucus nigra (SNA), Lens culinaris (LCA), Tetragonolobus purpureus (LTA), and Ulex europaeus (UEA) reactive glycotopes on maternal plasma and amniotic IgA were evaluated in relation to the progression of a normal human pregnancy, from the 2nd trimester, throughout the 3rd trimester, perinatal period, post-date pregnancy and delivery, by lectin-IgA-ELISA, using specific biotinylated lectins. The amniotic and maternal plasma IgA concentrations and a degree of SNA and LCA reactivity of maternal plasma IgA were almost unaltered during the normal pregnancy. The amniotic IgA from the 2nd trimester was decorated by MAA-, SNA-reactive and LCA-, LTA-, and UEA-reactive glycotopes. At the turn of the 2nd and 3rd trimesters the expression of MAA-, SNA-, LTA-, and UEA-reactive glycotopes, except for LCA-reactive, increased and remained almost at unaltered levels throughout the perinatal period and delivery. However, in the post-date pregnancy the expression of LCA-, LTA-, and UEA-reactive and SNA-reactive glycotopes were significantly higher. The unique fucosylated and sialylated glycovariants of amniotic IgA associated with the progression of the normal pregnancy may illustrate a general importance of carbohydrate-lectin receptor interactions in the control and modulation of biological events to ensuring homeostasis during pregnancy, protection and well-being of fetus.

Early stage fetal neocortex exhibits a complex ganglioside profile as revealed by high resolution tandem mass spectrometry

“…Obtained results indicated differences in the expression of mono/polysialylated as well as of O-acetylated species in the two ganglioside mixtures which support earlier hypothesis regarding the direct correlation between the sialylation and acetylation degree and brain developmental stage: a higher sialylation degree being specific for incipient developmental stages while a higher acetylation for more developed brains. Our findings are in agreement with the results of Orczyk-Pawiłowicz et al [37] who have studied the amniotic IgA structure during the same gestational stage i.e. the second trimester.…”

Longitudinal monitoring of immunoglobulin A glycosylation during pregnancy by simultaneous MALDI-FTICR-MS analysis of N- and O-glycopeptides

“…Sialic acids on N -glycans of the standard serum IgA samples analysed in this study were almost exclusively α2,6-linked (>95%), which is in line with previous reports41025. With regard to the level of sialylation of N -glycans, Orczyk-Pawilowicz et al .…”

“…With regard to the level of sialylation of N -glycans, Orczyk-Pawilowicz et al . reported no significant changes after delivery25. However, in the current study we have found that sialylation levels at Asn144 were lower after delivery.…”

“…Methods reported so far for the detection of IgA glycosylation involve lectin binding arrays252627, mass spectrometry (MS) in combination with various chromatographic strategies2361827282930 and liquid chromatography (LC) with fluorescence detection31. These methodologies lack specificity (lectins) and are time-consuming (LC-MS).…”

Human body symmetry and immune efficacy in healthy adults

“…The results were calculated using BD CellQuest software and expressed in cells/µl. Immunoglobulin level: Antibodies are capable of binding antigens with a high affinity and contribute to their effective elimination by various mechanisms that are activated by the complex antigen‐antibody. The main functions of antibodies include complement activation, opsonization and activation effector cells such as phagocytic cells, T cells, NK cells.Total IgA and IgG levels were measured in a participant's serum by the enzyme‐linked immunosorbent assay (ELISA) using previously calibrated reagents and a panel of serum‐sample dilutions (according to methods described by Orczyk‐Pawiłowicz et al, ). The absorbance was measured using a spectrophotometer (Asys UVM340, Biochrom).…”