Inhibitory ability of adherent blood cells from patients with chronic myeloid leukaemia on DNA-synthesis in non-adherent leukaemic cells and PHA-stimulated lymphocytes.

Mononuclear blood cells were isolated from patients with different types of leukaemia and studied in vitro with regard to cell functions - adhesiveness, phagocytosis, DNA synthesis and inhibitory effects of adherent cells on non-adherent leukaemic cells and PHA stimulated lymphocytes. Cells from patients with chronic myeloid leukaemia (CML) adhered to the plastic surface of the culture dishes and showed esterase staining reactions as monocytes/macrophages. They showed a normal capacity to ingest Candida albicans, while the digestion capacity appeared reduced. Non-adherent cells from CML showed a high ability to incorporate thymidine, indicating DNA synthesis. Adhesive cells from patients with CML inhibited DNA synthesis in nonadherent CML cells and in PHA-stimulated lymphocytes to about the same extent as adhesive cells from normal donors. Blood cells from acute myeloid leukaemia and chronic lymphocytic leukaemia showed on adhesiveness and a very low spontaneous thymidine incorporation.