IL10 and colitis: For example, Il10-/- B cells and Myd88-/- B cells lack an anti-inflammatory property,[16,19] and IL-10-producing regulatory B cells require IL-27 signaling-mediated IL-10-secretion by T cells to confer protection against T cell-mediated colitis.[16] Therefore, classification of the mucosal B cell population and evaluation of its functional aspects in regard to the interaction with other types of immune cells are important to understand the functions of the mucosal immune system in IBD.