Antibodies against circumsporozoite proteins of Plasmodium falciparum induced by natural infection.
Sera from 10 individuals who lived in a malaria endemic area, 10 patients with acute uncomplicated falciparum malaria and 10 patients with cerebral malaria and hyperimmune mouse serum were tested for their reactivities against Plasmodium falciparum sporozoite antigens by Western blot analysis using 125I-labeled staphylococcal protein A as the detecting reagent. These sera were shown by indirect immunofluorescence and/or circumsporozoite precipitation test to have antibodies reacting against the parasites. It was found that all serum antibodies from the three groups of individuals and the mouse serum reacted in a similar pattern with circumsporozoite (CS) proteins of P. falciparum. Ten sera from normal individuals were negative in all reactions. Monoclonal antibody (MAB) specific against CS proteins of the parasites showed that the proteins exhibited as four different molecular weight (MW) polypeptides, i.e., 67,000, 65,000, 60,000, and 58,000 daltons. These CS proteins of P. falciparum were found to be species and stage specific. Radioimmunoprecipitation using 35S-methionine-labeled parasites and sera of individuals from the various categories or MABs gave a similar result. Another protein antigen of P. falciparum sporozoites had a MW of 80,000 daltons. This antigen was not species specific, probably not membrane associated and was present in a minute quantity in the parasite's extract.
P
P
Tapchaisri
P
P
Dekumyoy
A
A
Asavanich
M
M
Chongsa-nguan
S
S
Tharavanij
T
T
Harinasuta
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000906:Antibodies / Q000032:analysis*; D000953:Antigens, Protozoan / Q000276:immunology*; D002648:Child; D000939:Epitopes / Q000032:analysis; D006801:Humans; D008288:Malaria / Q000276:immunology*; D051379:Mice; D008875:Middle Aged; D008970:Molecular Weight; D010963:Plasmodium falciparum / Q000276:immunology*; D013045:Species Specificity
D000906:Antibodies; D000953:Antigens, Protozoan; D000939:Epitopes