Immature B lymphocytes differentiate into mature B lymphocytes in the

Immature lymphocytes differentiate into antigen-sensitive lymphocytes in the primary lymphoid organs. Maturation of B lymphocytes takes place in the bone marrow while the maturation of T lymphocytes takes place in the thymus. The spleen and the lymph nodes are the secondary lymphoid organs in which mature B lymphocytes and T lymphocytes proliferate to become effector cells.