Further Studies on Guinea Pig and Rabbit Cytophilic Antibodies Directed Against Human Serum Albumin

Abstract

Cutaneous hypersensitivity, humoral antibody levels and antibody production by single cells were studied in guinea pigs and rabbits sensitized with HSA in the form of immune complexes. Studies with guinea pigs showed that immune complexes prepared with homologous immune globulin were more highly immunogenic than were complexes prepared with a heterologous source of immune globulin. Immunogenicity was demonstrated for the heterologous globulin portion of immune precipitates and antigenic competition was implicated in the reduced capacity of these complexes to induce hypersensitivity to HSA. The immune response patterns of rabbits immunized with HSA complexed with homologous immune globulin were comparable to those obtained with guinea pigs. Incorporation of immune precipitates in FC adjuvant was a prerequisite for the induction of delayed-type hypersensitivity; likewise, only animals sensitized in this manner produced significantly high levels of cytophilic anti-HSA antibody following skin testing.