How are B cells activated ? T-independent antigen T-dependent antigen processes ?
When an antigen enters the body and makes contact with a B- or T-, lymphocyte bearing the proper recognition site, the lymphocyte is stimulated to reproduce and form a clone. Its progeny (B or T) become either plasma cells( that secrete humoral antibodies with the same binding specificity as the original clone that differentiated in responce to the specific antigen) or lymphoblasts (which activate cellular immunity, i.e., phagocytic cells). Thus, B cells become plasma cells and T cells give rise to several types of effector cells. They may become (1) killer T cells, which eliminate foreign cells by lysis; (2) helper T cells, which aid B cells to differentiate and other T cells to proliferate;(3) suppressor T cells (4) amplifier T cells.