Immunization against Plasmodium falciparum with recombinant polypeptides produced in Escherichia coli

Two proteins produced in recombinant Escherichia coli and containing amino acid sequences from the Plasmodium falciparum precursor to major merozoite surface antigens (PMMSA) have been partially purified. These proteins, together with a preparation of merozoites, have been used to immunize animals. The antibody response and the degree of protection were compared. Animals immunized with merozoites produced antibodies reacting with many P. falciparum proteins, whereas a response specific for PMMSA was detected in those receiving the recombinant material. Incomplete protection was conferred to both groups and there was no apparent correlation between antibody levels and protection.