Title : Circulating levels of IL-17A in group B streptococcus-colonized pregnant women: A promising indicator of the risk of neonatal complications
Abstract:
Group B Streptococcus (GBS) frequently colonizes the maternal genital tract and can be a significant cause of severe maternal and neonatal infections. However, there is limited knowledge about the maternal immune and inflammatory responses to GBS colonization and transmission, especially in low- and middle-income countries. The objective of this study was to characterize the cytokine profiles in pregnant women colonized with GBS and to investigate their correlation with the occurrence of invasive GBS infection in their newborns. The study tracked GBS-colonized women from the third trimester of pregnancy until delivery, measuring cytokines in maternal and cord blood using Luminex technology and ELISA. Functional immune responses were further evaluated by measuring cytokine release in culture supernatants of blood cells after stimulation of pathogen-recognition receptors with TLR4 and TLR2 ligands. Finally, data from GBS-positive mothers were linked to clinical markers and neonatal outcomes to identify key inflammatory patterns. The study identified a distinct immune inflammatory signature in GBS-colonized mothers whose infants developed invasive disease. These mothers showed a significant diminution in IL-1β, IL-4, and IL-17A production, both in baseline circulation and following TLR ligand simulation. Notably, maternal IL-17A emerged as the primary predictive marker for the transmission and progression of neonatal invasive GBS disease. Measuring the circulating level of IL-17A, a major antibacterial mediator, in GBS-colonized mothers would be valuable in identifying those at risk for invasive neonatal disease.
