title: Evidence that protein kinase C differentially regulates the human T lymphocyte CD2 and CD3 surface antigens.
abstract: The purpose of the present study was to explore the effects of protein kinase C (PKC) stimulation on two cell surface receptors that regulate T cell growth: the T cell antigen receptor/CD3 complex and the CD2 antigen. The data show that PKC differentially regulates the expression and functions of CD2 and CD3 molecules. Thus, activation of PKC induced a decrease in cell surface levels of CD3 molecules but an increase in the expression of CD2 antigens. Additionally, prolonged stimulation of PKC inhibited subsequent T cell activation via CD3 but promoted activation via CD2 molecules. These results suggest that the CD2 cellular activation pathway would be preferred in T cells which have been exposed to stimulators of PKC. The molecular basis for the regulatory effects of PKC on CD3 and CD2 molecules and its physiological significance are discussed.
mesh_terms: D000911:Antibodies, Monoclonal; D000937:Antigen-Antibody Reactions; D000945:Antigens, Differentiation, T-Lymphocyte / Q000502:physiology*; D018801:CD2 Antigens; D017252:CD3 Complex; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000187:drug effects; D010703:Phorbol Esters / Q000494:pharmacology; D011493:Protein Kinase C / Q000502:physiology*; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D011971:Receptors, Immunologic / Q000502:physiology*; D013601:T-Lymphocytes / Q000502:physiology*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D017252:CD3 Complex; D010703:Phorbol Esters; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D011493:Protein Kinase C