Cloning and expression in Escherichia coli of a surface antigen of Plasmodium falciparum merozoites.

Open Access
Publisher Website
Google Scholar
Abstract
A complementary DNA library was constructed from mRNA purified from asexual blood forms of Plasmodium falciparum. Among the members of this library we have identified a plasmid (pMC31‐1) coding for a polypeptide exposed at the surface of merozoites, the invasive stage of the asexual cycle. This plasmid was identified by direct expression using both polyclonal and monoclonal antibodies specific for a schizont polypeptide of 200 kd which has been shown to be processed to an 83‐kd polypeptide expressed at the surface of merozoites. The cDNA portion of the pMC31‐1 plasmid hybridizes with DNA from three isolates of P. falciparum. Antisera raised against extracts of Escherichia coli harbouring pMC31‐1 react with surface and internal structures of schizonts and with the surface of merozoites from all the isolates of P. falciparum examined. These results suggest that plasmid pMC31‐1 encodes an antigen of value for the development of a vaccine against malaria.