Activation of protein kinases A and C increase lymphocyte penetration through endothelial monolayers.
A brief incubation of lymphocytes with either PMA, stimulating protein kinase C, or with dibutyryl-cAMP, leading to protein kinase A activation, led to increased lymphocyte penetration through intact endothelial monolayers in vitro. The PMA-induced penetration could be dose-dependently down-regulated with a protein kinase C inhibitor, H7. Similarly HA 1004, being mainly a protein kinase A inhibitor, decreased the dibutyryl-cAMP induced penetration. Treatment of lymphocytes with PMA and cAMP did not alter the expression of CD44 homing receptors on lymphocytes. Stimulation of lymphocytes with dibutyryl-cGMP or calcium ionophore had no effect on lymphocyte penetration. These results suggest that activation of both protein kinases A and C is important in the lymphocyte binding to endothelium.
Renkonen
R
R
Department of Bacteriology and Immunology, University of Helsinki, Finland.
D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology; D000943:Antigens, Differentiation / Q000276:immunology; D003994:Bucladesine / Q000494:pharmacology; D002460:Cell Line; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D008214:Lymphocytes / Q000201:enzymology / Q000276:immunology / Q000502:physiology*; D011493:Protein Kinase C / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000378:metabolism*; D016201:Receptors, Lymphocyte Homing; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000943:Antigens, Differentiation; D011971:Receptors, Immunologic; D016201:Receptors, Lymphocyte Homing; D003994:Bucladesine; D011494:Protein Kinases; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate