title: Modulation of human T-cell differentiation markers by 12-O-tetradecanoylphorbol-13-acetate.
abstract: The analysis of seven 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 molecular weight 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 PHA, 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 for 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.
mesh_terms: D015720:5'-Nucleotidase; D000243:Adenosine Deaminase / Q000276:immunology; D000328:Adult; D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D003114:Colony-Forming Units Assay; D003561:Cytarabine / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D004253:DNA Nucleotidylexotransferase; D000949:Histocompatibility Antigens Class II; D006801:Humans; D007942:Leukemia, Experimental / Q000276:immunology; D009708:Nucleotidases; D010704:Phorbols / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D012397:Rosette Formation; D012756:Sheep; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D000949:Histocompatibility Antigens Class II; D010704:Phorbols; D010835:Phytohemagglutinins; D003561:Cytarabine; D004247:DNA; D004253:DNA Nucleotidylexotransferase; D009708:Nucleotidases; D015720:5'-Nucleotidase; D000243:Adenosine Deaminase; D013755:Tetradecanoylphorbol Acetate