Do Long-Lived Plasma Cells Maintain a Healthy Microbiota in the Gut?

Disruptions to the gut microbiota have been associated with a variety of diseases. Understanding the underlying mechanisms that regulate the maintenance of a healthy microbiota may therefore have therapeutic implications. Secretory IgA play a unique role in immune-microbiota crosstalk by directly binding to bacteria in the gut lumen. Microbe-specific IgA responses co-develop with the assembly of the gut microbiota during infancy, and resemble those of adults by 2 years postnatally in the healthy host. We propose here that microbiota-specific IgA-producing gut plasma cells generated during infancy live for many decades and contribute to a stable microbiota community. We furthermore suggest that members of the microbiota that induce long-lasting IgA responses in the gut are putative targets for therapeutic interventions.