Interleukin 1-induced lymphocyte binding to endothelial cells. Role of cAMP as a second messenger.
Interleukin 1 (IL 1) is a potent protein mediator of inflammation. Among other things it increases the number of lymphocytes adhering to endothelial cell monolayers. We analyzed the signal transduction during IL 1-induced lymphocyte binding. Dibutyryl cyclic AMP, which is a cAMP analog able to penetrate into the cytosol, increased lymphocyte binding to the same extent as IL 1. Direct activation of adenylate cyclase by forskolin enhanced also lymphocyte binding. IL 1 increased the level of cytosolic cAMP in a time- and dose-dependent manner measured with radioimmunoassay. 2',5'-Dideoxyadenosine, which is an inhibitor of adenylate cyclase, decreased both the IL 1-induced lymphocyte binding to endothelial cells and elevation in cytosolic cAMP levels. Lymphocyte binding increased with cytosolic cAMP levels in accordance with elevation of IL 1 concentration. These results suggest that cAMP is essential in signal transduction during IL 1-induced lymphocyte binding to cultured endothelial cell monolayers.
Renkonen
R
R
Department of Bacteriology Immunology, University of Helsinki, Finland.
Mattila
P
P
Häyry
P
P
Ustinov
J
J
D000818:Animals; D002448:Cell Adhesion / Q000276:immunology; D000242:Cyclic AMP / Q000378:metabolism / Q000502:physiology*; D003600:Cytosol / Q000032:analysis; D004730:Endothelium, Vascular / Q000276:immunology*; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000502:physiology*; D008214:Lymphocytes / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D015290:Second Messenger Systems / Q000276:immunology
D007375:Interleukin-1; D000242:Cyclic AMP