Microbial symbionts regulate the primary Ig repertoire.

ABSTRACT: The ability of immunoglobulin (Ig) to recognize pathogens is critical for optimal immune fitness. Early events that shape preimmune Ig repertoires, expressed on IgM⁺ IgD⁺ B cells as B cell receptors (BCRs), are poorly defined. Here, we studied germ-free mice and conventionalized littermates to explore the hypothesis that symbiotic microbes help shape the preimmune Ig repertoire. Ig-binding assays showed that exposure to conventional microbial symbionts enriched frequencies of antibacterial IgM⁺ IgD⁺ B cells in intestine and spleen. This enrichment affected follicular B cells, involving a diverse set of Ig-variable region gene segments, and was T cell-independent. Functionally, enrichment of microbe reactivity primed basal levels of small intestin

SUBMITTER: Chen Y 

PROVIDER: S-EPMC5940265 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature