Antibody Secreting Cells Are Critically Dependent on Integrin α4β7/MAdCAM-1 for Intestinal Recruitment and Control of the Microbiota during Chronic Colitis

β7 deficiency and MAdCAM-1 blockade specifically depleted antibody secreting cells from the colonic LP, leading to a fecal pan-immunoglobulin deficit, severe colitis, and alterations of microbiota composition.