Multipotent human hematopoietic cell line K562: lineage-specific constitutive and inducible antigens.

K562 cells have been reported to display a variety of non-erythroid properties. Using 28 lineage-specific monoclonal antibodies, we analysed which antigens are present spontaneously and which are inducible by a variety of agents. The data suggest that (1) antigens of a given lineage are preferentially responsive to certain inducers, e.g. megakaryocytic antigens to phorbol ester, and (2) a given inducer may influence antigens of different lineages in opposite directions, e.g. phorbol dibutyrate, not only induces megakaryocytic antigens, but also decreases granulocyte and erythroid antigens. We conclude that the K562 cell, despite its malignant origin, retains some capacity for expression of alternative programs of differentiation, a characteristic of the normal multipotent hematopoietic stem cell.