Expression of the CD4 molecule on acute nonlymphocytic leukemia (ANLL) cell lines

Mature and immature monocytes express the CD4 molecule similar to that expressed on lymphocytes. Since monocytes and cells of myeloid lineage are derived from a common progenitor, we studied a panel of nine myeloid leukemia cell lines for the expression of the CD4 molecule. We found that six of nine myeloid leukemia cell lines (U937, KG1-B, HL-60, THP-1, HEL 92.1.7, KMOE) expressed CD4, the exceptions being the erythroleukemia line K562, myeloblast line KG1-REV, and megakaryocytic line, CHRF-288. SDS-PAGE analysis of HL-60 cells immunoprecipitated with OKT4 showed the presence of a 55 kd molecule similar in weight to that seen on lymphocytes. These data suggest that some myeloid progenitor cells express the CD4 molecule and that the CD4 may have a broader distribution within hematopoietic cells.