MODULATION OF HUMAN T-CELL DIFFERENTIATION MARKERS BY 12-O-TETRADECANOYLPHORBOL-13-ACETATE

  • 1 January 1981
    • journal article
    • research article
    • Vol. 3  (4-5) , 307-318
Abstract
The analysis of 7 differentiation markers following incubation with the tumor promotor 12-O-tetradecanoylphorbol-13-acetate (TPA) was examined in the human leukemic T-cell line MOLT-3. Significant changes were observed in the activity of the markers terminal deoxynucleotidyl transferase (TdT), spontaneous proliferation and the ability of these cells to bind sheep erythrocytes. Levels of human thymus-leukemia-associated antigen (HThy-L), recently identified as a low MW form of adenosine deaminase (ADA), were reduced by about 50%. No significant changes were observed in ecto-5''-nucleotidase (5''-NT) activities, in the proliferative response to phytohemagglutinin or in the expression of Ia-like antigens. These data and the time kinetics of the changes suggest that following incubation of these T lymphoblasts with TPA there is a sequential loss of TdT, loss of the capacity of spontaneous proliferation and the appearance of receptors for sheep erythrocytes. Subsequently there is a decrease in the level of HThy-L/ADA. This sequence appears to follow that proposed for prethymic precursor T cell differentiation following activation with thymic epithelium.