Immunoglobulin G Glycosylation Changes in Aging and Other Inflammatory Conditions

Early neonatal complications in pregnant women with gestational diabetes mellitus and the effects of glycemic control on neonatal infection

BACKGROUND

Gestational diabetes mellitus (GDM) has become increasingly prevalent globally. Glycemic control in pregnant women with GDM has a critical role in neonatal complications.

AIM

To analyze the early neonatal complications in GDM, and examine the effect of blood glucose control level on neonatal infection.

METHODS

The clinical data of 236 pregnant women with GDM and 240 healthy pregnant women and newborns during from March 2020 to December 2021 the same period were retrospectively analyzed, and the early complications in newborns in the two groups were compared. The patients were divided into the conforming glycemic control group (CGC group) and the non-conforming glycemic control group (NCGC group) based on whether glycemic control in the pregnant women with GDM conformed to standards. Baseline data, immune function, infection-related markers, and infection rates in neonates were compared between the two groups.

RESULTS

The incidence of neonatal complications in the 236 neonates in the GDM group was significantly higher than that in the control group (P < 0.05). Pregnant women with GDM in the NCGC group (n = 178) had significantly higher fasting plasma glucose, 2 h postprandial blood glucose and glycated hemoglobin A1C levels than those in the CGC group (n = 58) (P < 0.05). There were no differences in baseline data between the two groups (P > 0.05). Additionally, the NCGC group had significantly decreased peripheral blood CD3+, CD4+, CD8+ T cell ratios, CD4/CD8 ratios and immunoglobulin G in neonates compared with the CGC group (P < 0.05), while white blood cells, serum procalcitonin and C-reactive protein levels increased significantly. The neonatal infection rate was also significantly increased in the NCGC group (P < 0.05).

CONCLUSION

The risk of neonatal complications increased in pregnant women with GDM. Poor glycemic control decreased neonatal immune function, and increased the incidence of neonatal infections.

Definition of IgG Subclass-Specific Glycopatterns in Idiopathic Membranous Nephropathy: Aberrant IgG Glycoforms in Blood

The podocyte injury, and consequent proteinuria, that characterize the pathology of idiopathic membranous nephropathy (IMN) is mediated by an autoimmune reaction against podocyte antigens. In particular, the activation of pathways leading to abundant renal deposits of complement is likely to involve the binding of mannose-binding lectin (MBL) to aberrant glycans on immunoglobulins. To obtain a landscape of circulatory IgG Fc glycosylation characterizing this disease, we conducted a systematic N-glycan profiling study of IgG1, 2, and 4 by mass spectrometry. The cohort included 57 IMN patients, a pathological control group with nephrotic syndrome (PN) (n = 20), and 88 healthy control subjects. The effect of sex and age was assessed in all groups and controlled by rigorous matching. Several IgG Fc glycan traits were found to be associated with IMN. Interestingly, among them, only IgG4-related results were specific for IMN and not for PN. Hypo-galactosylation of IgG4, already shown for IMN, was observed to occur in the absence of core fucose, in line with a probable increase of pro-inflammatory IgG. In addition, elevated levels of fucosylated IgG4, along with low levels of hybrid-type glycans, were detected. Some of these IgG4 alterations are likely to be more pronounced in high PLA2R (phospholipase A2 receptor) patients. IgG Fc glycosylation patterns associated with IMN warrant further studies of their role in disease mechanisms and may eventually enrich the diagnostic spectrum regarding patient stratification.