Maturation asynchrony in leukemic cells. An abnormal combination of normal cell markers.

Multiple monoclonal antibodies and enzyme assays were used to study maturity markers (myelo-peroxidase) and immaturity markers (terminal transferase, HLA-2) in acute myeloid leukemia cells from 35 patients. In 8 of the patients, indications were found of an expression of maturity and immaturity markers on the same cells, here in called maturation asynchrony. It is suggested that the orderly appearance and disappearance of markers during the maturation of normal cells is disordered in malignant cells, and that single markers should be used with caution for the maturation classification of tumors. The simultaneous expression of maturity and immaturity marker by tumor cells could explain also why such cells can be recognized as abnormal even in the absence of tumor specific antigens.