The human intestine is densely colonized with commensal microbes that stimulate the
immune system. While secretory Immunoglobulin (Ig) A is known to play a crucial role in gut
microbiota compartmentalization, secretory IgM, and systemic IgG have recently been
highlighted in host-microbiota interactions as well. In this review, we discuss important
aspects of secretory IgA biology, but rather than focusing on mechanistic aspects of IgA
impact on microbiota, we stress the current knowledge of systemic antibody responses to …