Alloimmune IgG binds and modulates cardiac beta-adrenoceptor activity.

STERIN-BORDA L; CREMASCHI G; PASCUAL J; GENARO A; BORDA E

CLINICAL AND EXPERIMENTAL IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 1984 vol. 58 p. 223 - 228

0009-9104

Purified IgG from murine alloimmune sera directed against class I products from the major histocompatibility complex of the mouse, could bind to the beta-adrenoceptors and stimulate contractile activity of myocardium. Immune IgG inhibited the binding of (-) 3H-DHA to beta-adrenoceptors of mouse myocardial membranes behaving as a competitive inhibitor. Moreover, immune IgG induced positive inotropic and chronotropic effects on isolated mouse atria. These effects could be blocked by beta-adrenoceptors antagonists. Data prove that immune IgG directed against specific alloantigens are able to recognize the beta-adrenoceptors and mimic the stimulation of the beta-adrenoceptor agonist.