title: Cross-reactivity of antibody against an epitope of the Plasmodium falciparum second merozoite surface antigen.
abstract: Monoclonal antibodies directed against the 51 kD merozoite surface antigen of Plasmodium falciparum also bind to other antigens within the infected cell. The sizes of these cross-reacting antigens have been characterized. Immunofluorescence due to the reaction of one of the monoclonal antibodies with these cross-reacting antigens was localized in the intra-erythrocytic parasite and in granules in the infected red cell cytoplasm. This immunofluorescence could be distinguished from the merozoite surface antigen in parasite lines with a variant serotype of the merozoite surface antigen which fails to react with the monoclonal antibodies. It was found that the in-vitro growth inhibition caused by the presence of one of the monoclonal antibodies, 8G10/48, was dependent on the expression of the corresponding serotype of merozoite surface antigen, a finding consistent with the inhibitory effect of this antibody being primarily directed against the merozoite surface antigen and not the cross-reacting antigens. Analysis of the frequency at which epitopes occur suggests that such cross-reacting proteins will be commonly seen in malaria, without the need to postulate a selective advantage for such cross-reacting specificities.
authors: Queensland Institute of Medical Research, Brisbane, Australia.
authors: A
authors: A
authors: Saul
authors: R
authors: R
authors: Lord
authors: G
authors: G
authors: Jones
authors: H M
authors: HM
authors: Geysen
authors: J
authors: J
authors: Gale
authors: R
authors: R
authors: Mollard
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000913:Antibodies, Protozoan / Q000276:immunology*; D000953:Antigens, Protozoan / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology; D003429:Cross Reactions; D000939:Epitopes / Q000276:immunology; D005455:Fluorescent Antibody Technique; D007042:Hypoxanthines / Q000378:metabolism; D015151:Immunoblotting; D010963:Plasmodium falciparum / Q000254:growth & development / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000954:Antigens, Surface; D000939:Epitopes; D007042:Hypoxanthines