Involvement of spectrin and ATP in infection of resealed erythrocyte ghosts by the human malarial parasite, Plasmodium falciparum.

Open Access
Publisher Website
Google Scholar
Abstract
Resealed erythrocyte ghosts were prepared under different experimental conditions and were tested in vitro for susceptibility to infection with the human malarial parasite, P. falciparum. Resealed ghosts, prepared by dialyzing erythrocytes in narrow membrane tubing against low ionic strength buffer that was supplemented with Mg ATP, were as susceptible to parasite infection as were normal erythrocytes. There was a direct correlation between intraerythrocytic ATP content and susceptibility to parasite infection. Neither MgCl2 nor Na ATP could be substituted for Mg ATP in maintaining high intraerythrocytic ATP concentration. When resealed ghosts were loaded with antispectrin IgG, malaria merozoite invasion was inhibited. At an average intracellular antispectrin IgG concentration of 3.5 .mu.g/108 cells, there was a 35% inhibition of parasite invasion. This inhibition was due to spectrin crosslinking within the resealed ghosts, since the monovalent, Fab'' fragments of antispectrin IgG had no inhibitory effect on invasion. Evidently, the cytoskeleton plays a role in the complex process of merozoite entry into the host erythrocyte.