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 o...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.展开更多
文摘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.