The Study and Comparison of the Antigenic Structure of the Primate Malarias

摘要

The objective of this study is to compare strains and species of primate plasmodia using the newer analytical methods in order to determine whether physiological differences among them are associated with differences in antigenic composition. Harvests of simian and human plasmodia were collected in London, Davis, Thailand and the Gambia. Harvests of Plasmodium knowlesi, Plasmodium cynomolgi and Plasmodium cynomolgi bastianellii each contain a series of plasmodial antigens, as demonstrated by methods of double diffusion in gel. While homologous rabbit antiserum contains the greatest number of antiplasmodial precipitins, cross reactions occur between each product and heterologous antisera. Cross reactions are more numerous between closely related plasmodia than between those more phylogenetically distant from one another. Primate plasmodial harvests are contaminated with host cell antigens which can be removed from the appropriate antisera by absorption with uninfected host cell antigen. Fifty serum samples from Gambian children, most of which probably contained antifalciparum precipitin, failed to cross-react with P. knowlesi or with P. cynomolgi bastianellii antigen. Each of approximately 70 primate plasmodial products is being studied by disc electrophoresis and densitometry. Each contains a series (up to 20) of protein components. It is sought to pinpoint the host contaminants in this array of proteins and to determine whether the plasmodial antigenic profile of a given strain is constant and replicable. (Author)