Role of the Innate Immune System and Host-Commensal Mutualism.- Molecular Networks Orchestrating GALT Development.- Lymphoid Tissue Inducer Cells in Intestinal Immunity.- Specificity and Plasticity of Memory LymphocyteMigration.- IgA Adaptation to the Presence of Commensal Bacteria in the Intestine.- Intestinal IgA Synthesis: A Primitive Form of Adaptive Immunity That Regulates Microbial Communities in the Gut.- B Cell Recruitment and Selection in Mouse GALT Germinal Centers.- Structural Insights into Antibody-Mediated Mucosal Immunity.Includes supplementary material: sn.pub/extras