TPA, tumor promoter-induced suppression of immunoglobulin secretion in human blood lymphocytes.

摘要: 12-O-Tetradecanoylphorbol-13-acetate (TPA) modulates DNA synthesis and differentiation of normal malignant human lymphoid cells. Using the reverse plaque forming assay radioimmunoassay, we showed that nontoxic concentrations TPA (5 to 10 ng/ml) inhibited Ig secretion peripheral blood lymphocytes. This inhibition was dependent on T lymphocytes not monocytes; treatment B cell-enriched fraction slightly enhanced secretion. Suppression evident when proportion TPA-pretreated exceeded 50%. TPA-induced suppressor cells were present in both OKT8+ (suppressor/cytotoxic) OKT4+ ("helper/inducer") subpopulations. The suppression diminished but abolished by irradiation In addition, modulated expression OKT4 antigen, whereas OKT8, 9.6 (sheep erythrocyte receptors) surface remained unchanged. Modulation energy blocked a maximal saturation receptors at 4 degrees C. We postulate is cell likely be associated with proliferation activation induction