The effect of antibody and complement on perfused hearts: a model for the study of xenograft rejection phenomenon

An in vitro heart perfusion system was developed to study the effect of antibody and complement on hearts in vitro, as a model to quantitatively evaluate factors involved in xenograft rejection. Both guinea pig and rabbit hearts were tested with various reagents. Perfusion of hearts with normal autologous or "homologous" sera did not induce rejection, while "heterologous" sera, normal or immune, arrested cardiac function. Either the inactivation of certain complement components or the absence of antibodies against heart tissue prevented rejection as determined by lack of change in electrocardiogram and alterations in ultrastructure. Antibody alone had no effect. A lethal effect of C6-deficient rabbit serum on guinea pig hearts was prevented by 2 antihistamines, Chlortripolon and Benadryl.