Inhibition:•Fecal (53)*•Fecal in pups (male pups more sensitive than female) from TCDD-exposed dams due to impaired chemotaxis of B1 cells to gut (37)* % IgA primary splenic B cells after in vitro stimulation (51)*Increase:•Fecal (males more sensitive than females) (54)•Fecal, TCDF exposure (55)•Fecal and colon in colitis model (56)*•Fecal OVA-specific IgA in oral tolerance model (50)•Plasma influenza-specific (27)•B-cell line (33, 57)*No effect:•IgA AFC in mediastinal lymph node (27). Here, CD79A is linked to colitis.