Immunologic Enhancement in Malaria Infection (Plasmodium Berghei)

Abstract

Abstract Immunologic enhancement of malaria (Plasmodium berghei) comparable to that described in tumor and transplantation immunity could be produced by a variety of active and passive immunization procedures, using quantities of antigen comparable to those commonly employed. Much greater quantities were required for the development of some degree of protection. The clinical importance and the possible relationship to tumor and transplantation immunity, and the possible mechanisms of this phenomenon, are discussed. Attempts at active and passive immunization against malarial parasites not only frequently failed to show beneficial results, but often led to exacerbation of the challenge infection. The challenge infection is influenced by various antibodies in different proportions. Non-cytotoxic antibody appears to act as an enhancing agent in the absence of a second, protective antibody; but it may play a minor role, or even be a decisive factor, in the presence of a protective antibody. The observed enhancement phenomenon appears to resemble the immunologic enhancement of tumor growth.