[Evidence for CFU-C self-replication (author's transl)].

To explore the proliferative potential of committed myeloid progenitor cells (CFU-C), we placed suspensions of mouse spleen cells in short-term liquid culture with colony stimulating activity and subcultured the cells in agar at intervals to assay for CFU-C. Prior to liquid culture, aliquots of spleen cells were exposed briefly to hypotonic conditions to lyse CFU-S but not CFU-C. A 50-fold increase in CFU-C was observed in control cultures. The pattern of CFU-C proliferation was not altered significantly by hypotonic lysis despite the fact that this treatment effectively removed CFU-S. These results support the hypothesis that CFU-C are capable of self-replication and permit a model of hematopoiesis in which expansion of the granulopoietic pool is controlled, in part, at the level of the CFU-C.