The Wanderings of Gut-Derived IgA Plasma Cells: Impact on Systemic Immune Responses

Humoral immunity is mainly mediated by a B cell population highly specialized to synthesize and secrete large quantities of antibodies - the antibody-secreting cells (ASC). In the gastrointestinal environment, a mixture of foreign antigens from the diet, commensal microbiota as well as occasional harmful pathogens lead to a constant differentiation of B cells into ASC. Due to this permanent immune response, more than 80% of mammalian ASC reside in the gut, of which most express immunoglobulin A (IgA). IgA antibodies contribute to intestinal homeostasis and can mediate protective immunity. Recent evidence points at a role for gut-derived ASC in modulating immune responses also outside of mucosal tissues. We here summarize recent evidence for wandering ASC, their antibodies and their involvement in systemic immune responses.

Automated summary

Humoral immunity is mediated by ASC specialized in synthesizing antibodies, with over 80% residing in the gut and most expressing IgA. These antibodies play a crucial role in maintaining intestinal homeostasis and protective immunity, while also being involved in immune responses outside of mucosal tissues.