HETEROGENEITY OF THE RESPONSE OF CHRONIC LYMPHOCYTIC-LEUKEMIA CELLS TO PHORBOL ESTER

  • 1 January 1982
    • journal article
    • research article
    • Vol. 60  (5) , 1082-1088
Abstract
The ability of the tumor promotor 12-O-tetradecanoylphorbol 13-acetate (TPA) to induce differentiation of leukemic cells was studied in 10 patients with chronic lymphocytic leukemia (CLL). An increase in modal volume and an enhancement of the capacity of the leukemic cells to stimulate in mixed lymphocyte reaction (MLR) was seen in the majority of cases. A significant increase in Ia expression was observed upon culture of leukemic cells with TPA in 6 of the 10 cases; 5 of these cases also showed an induction of cytoplasmic IgM production. Correlations between the phenotypic markers of the leukemic cells and their ability to respond to TPA were evaluated. CLL cells with low amounts of surface Ig, a volume .ltoreq. 165 ft and relatively low Ia expression responded well to TPA. Cells with bright surface Ig, a volume .gtoreq. 178 ft and elevated amounts of Ia responded poorly to TPA. Apparently, differences in the response of B leukemic cells to TPA reflect the underlying heterogeneity of the leukemic cells and might correlate with their stage of maturation.