Antibody-induced lysis of nucleated cells in agar gel

Cytolysis of nucleated cells incorporated into agar gel was studied using hetero- and isoantibodies. Evidence was presented that IgG and IgM antibodies may participate in these reactions. Studies on the lytic activity of rabbit anti-rat sera showed that antibodies inducing lysis of rat thymus cells are directed against species-specific cell surface antigens. Evidence was presented that some of these antigens are shared by nucleated cells and erythrocytes whereas other antigens are present on nucleated cells only. Tests with rabbit anti-sheep erythrocyte serum demonstrated that Forssman antibodies elicit lysis of nucleated cells originating from Forssman-positive species. It was also shown that infectious mononucleosis sera are capable of inducing lysis of sheep and bovine nucleated cells. In studying human renal transplantation sera, cytolysis of kidney cells was induced by sera obtained from recipients after removal of rejected grafts or pretransplantation sera of recipients who rejected hyperacutely their grafts. These results were consistent with those observed in previous studies by means of mixed agglutination.

Immunological effects of thermal injury. I. Inhibition of spermatogenesis in guinea pigs

Unilateral thermal injury to guinea pig testes has elicited the formation of organ- and species-specific antibodies against a testicular antigen. The antibodies were of an IgG₁ nature, and reacted with autologous as well as homologous testicular extracts. A significant number of burned animals showed pathological changes in the contralateral testis, which were similar to those observed after the induction of experimental allergic orchitis by active immunization with testicular tissue. These results indicate that thermal injury may be associated with autoimmunization of the host by the injured organ.

Heterophile antibodies in human transplantation

Sensitization of human recipients with transplantation antigens (leucocytes, skin, or kidney allografts) has resulted in the appearance of serum hemagglutinins directed against sheep, guinea pig, and rat erythrocytes. Such hemagglutinins have been identified as IgG and IgM antibodies. Their appearance was not related to AB0 erythrocyte group incompatibility between donors and recipients, and the antibodies were not of the Forssman or Paul-Bunnel type. The antibody responses appeared to be primarily directed against antigen(s) present on rat erythrocytes, but shared to varying extents by other species. The peak antibody titers occurred in association with allograft rejection. In this regard, they may be of interest as a possible early warning system for the diagnosis and prompt management of rejection crises in clinical organ transplantation.