Two new human myeloid cell lines derived from acute promyelocytic leukemia and chronic myelocytic leukemia.

Two new human myeloid cell lines, PL-21 and KCL-22, were established from acute promyelocytic leukemia and chronic myelocytic leukemia, respectively. PL-21 was positive to peroxidase staining and differentiated into mature myeloid cells in vitro. KCL-22 had Ph1 chromosomes and differentiated into granulocytes in vivo.