Immunoprophylaxis of Malaria: Sporozoite-Induced Immunity

Abstract

This chapter reviews the state of knowledge of immunization against malaria using sporozoites as immunizing agents and summarizes recent progress in this field. The demonstration of the immunogenicity of the sporozoite stage and of the occurrence of sporozoite-induced protection was first provided by the classical experiments of Mulligan et al. (1941) on avian malaria. Since then, a considerable amount of information on sporozoite-induced immunity has been obtained through experimental work using the rodent and, more recently, the simian malaria system. We intend to critically review these findings and to correlate them with the information obtained in preliminary vaccination attempts in humans, performed by immunization through the bite of infected irradiated mosquitoes (Clyde et al. 1973a, 1973b, 1975; Rieckmann et al. 1974). Furthermore, we will delineate what we consider to be some of the basic deficiencies in our knowledge of sporozoite-induced immunity and indicate some potentially productive future experimental approaches directed primarily at clarifying protective mechanisms and potentiating the sporozoite-induced immune response.