B cells and the intestinal microbiome in time, space and place

Semin Immunol. 2023 Jul 18;69:101806. doi: 10.1016/j.smim.2023.101806. Online ahead of print.ABSTRACTThe gut immune system is shaped by the continuous interaction with the microbiota. Here we dissect temporal, spatial and contextual layers of gut B cell responses. The microbiota impacts on the selection of the developing pool of pre-immune B cells that serves as substrate for B cell activation, expansion and differentiation. However, various aspects of the gut B cell response display unique features. In particular, occurrence of somatically mutated B cells, chronic gut germinal centers in T cell-deficient settings and polyreactive binding of gut IgA to the microbiota questioned the nature and microbiota-specificity of gut germinal centers. We propose a model to reconcile these observations incorporating recent work demonstrating microbiota-specificity of gut germinal centers. We speculate that adjuvant effects of the microbiota might modify permissiveness for B cell to enter and exit gut germinal centers. We propose that separating aspects of time, space and place facilitate the occasionally puzzling discussion of gut B cell responses to the microbiota.PMID:37473559 | DOI:10.1016/j.smim.2023.101806

Source: Seminars in Immunology - July 20, 2023 Category: Allergy & Immunology Authors: Oliver Pabst Carla R Nowosad Source Type: research