[Migration of natural killer precursors from the bone marrow to the spleen]

The kinetics of the migration of the precursors of natural killer cells (NKC) from the bone marrow to the peripheral lymphoid organs has been studied. The total irradiation of C57BL/6 mice, BALB/c mice and (CBA X X C57BL/6)F1 hybrid mice in a lethal dose has been found to completely inhibit NKC. The partial protection of the bone marrow during irradiation leads to the complete regeneration of NKC in the spleen in 30-60 days. On the contrary, in the lymph nodes no NKC repopulation has been observed. The possible mechanisms of the migration of the precursors of NKC from the bone marrow are discussed. It is suggested that the precursors of NKC migrate from the bone marrow and finally differentiate into NKC in the spleen.