摘要
Background： Plasmodium falciparum malaria remains a major life-threatening disease. Recently, the Plasmodium apoptosis-linked pathogenicity factors （PALPF） have been identified. These antigens PALPF are expressed only by P falciparum-infected erythrocytes triggering endothelial cell apoptosis （apoptogenic）. Methods： We designed ten synthetic peptides （PI to P10） from PALPF： PF07 0032, PF10_0226, PFI0130c, PFD0875c and MAL13P1.206, and analyzed their antigenicity with an ELISA method using plasma samples from subjects living in Dienga, Gabon. Results： Four peptides showed good reactivity with human antibodies. The prevalence rate of specific IgG was 61%, 51%, 44% and 34% for P5, P6, P4 and P2, respectively. The median optical density of total IgG anti-P2 was higher than that directed against P4 and P6 （P = 0.009; P = 0.012 respectively）. The prevalence rate oflgG subclasses determined with plasma samples recognizing peptide 5 for IgGl, 2, 3 and 4 isotypes was 69%, 45%, 76% and 62%, respectively. All the subjects had at least one immunoglobulin subclass, while 13 （44%） had both IgG1 and IgG3 antibodies. There was no significant difference in the prevalence rate of anti-P5 IgG1, IgG3 and IgG4. Conclusion： These results warrant further immunogenicity studies of peptides 2, 4, 5 and 6 with a view of a tentative to antimalarial vaccine development.
