Maternal gut microbiome–induced IgG regulates neonatal gut microbiome and immunity

Abstract

The gut microbiome elicits antigen-specific immunoglobulin G (IgG) at steady state that cross-reacts to pathogens to confer protection against systemic infection. The role of gut microbiome–specific IgG antibodies in the development of the gut microbiome and immunity against enteric pathogens in early life, however, remains largely undefined. In this study, we show that gut microbiome–induced maternal IgG is transferred to the neonatal intestine through maternal milk via the neonatal Fc receptor and directly inhibits Citrobacter rodentium colonization and attachment to the mucosa. Enhanced neonatal immunity against oral C. rodentium infection was observed after maternal immunization with a gut microbiome–derived IgG antigen, outer membrane protein A, or induction of IgG-inducing gut bacteria. Furthermore, by generating a gene-targeted mouse model with complete IgG deficiency, we demonstrate that IgG knockout neonates are more susceptible to C. rodentium infection and exhibit alterations of the gut microbiome that promote differentiation of interleukin-17A–producing γδ T cells in the intestine, which persist into adulthood and contribute to increased disease severity in a dextran sulfate sodium–induced mouse model of colitis. Together, our studies have defined a critical role for maternal gut microbiome–specific IgG antibodies in promoting immunity against enteric pathogens and shaping the development of the gut microbiome and immune cells in early life.

Fournier’s Gangrene Post Circumcision in a Tertiary Hospital in Southern Nigeria

“…The immunity of a neonate is poorly developed and as such may not be competent in fighting against the polymicrobial organisms associated with FG. 12,13,14 There are epigenetic regulation of pediatric and neonatal immune systems which may account for the relative immunosuppression. 12 The median age of Fournier's gangrene in this study is 14days.…”

Necrotizing enterocolitis: Bench to bedside approaches and advancing our understanding of disease pathogenesis

“…The majority of placental IgG transfer occurs after 28 weeks of gestation. IgG levels reach 50% maternal concentration between 28 and 33 weeks gestation and will rise above maternal levels by 20%–30% at term ( 43 , 44 ). It is possible that low IgG levels in preterm infants may predispose these infants to develop NEC.…”

Microbial Enterotypes Shape the Divergence in Gut Fermentation, Host Metabolism, and Growth Rate of Young Goats

“…We also found that serum IgG was decreased in cluster 1 compared to that in cluster 2. As the most abundant serum immunoglobulin, IgG is conventionally linked to systemic infection because its induction requires the crossing of the barrier by antigens ( 34 – 36 ). High IgG immune responses generally occur during some specific disease status, such as in inflammatory bowel disease, in which the intestinal barrier is disrupted and pathogenic microorganisms translocate from the lumen ( 37 – 39 ).…”