Abstract
The antigen, 2, 4-dinitrophenylated and alum-precipitated bovine serum albumin (DNP-AP-BSA), was inoculated from the mouse foot pads into popliteal lymph nodes. The DNP-BSA-bearing phagocytes were first found in the paracortex, which was the thymus (T)-dependent area, at 3 hr after inoculation. Subsequently, at 1 week after inoculation, germinal centers containing a few T cells were formed within the lymphoid follicles in close contact with the T-dependent area. At 2 weeks after inoculation, crescent-shaped networks of DNP-BSA accompanying the IgG were observed in the peripheral region of germinal centers. These findings show that the cooperation of phagocytes, T cells and B cells against thymus dependent antigens may be indispensable in the formation of germinal centers and in the retention of their function in lymphocyte proliferation.
