Influence of erythrocyte membrane components on malaria merozoite invasion.

Chymotrypsin- and Pronase-treated human erythrocytes were refractory to invasion by P. knowlesi merozoites; invasion was not inhibited by trypsin or neurammidase treatment. These data implicate a surface protein other than sialoglycoprotein as the receptor site for merozoites. Invasion of rhesus erythrocytes was unaffected by pretreatment with these enzymes. Differences in membrane structure of erythrocytes from various species may explain the absence of an enzyme effect on rhesus erythrocytes.