title: Lymphocyte responses to Plasmodium falciparum ring-infected erythrocyte surface antigen (Pf155/RESA) peptides in individuals with naturally acquired Plasmodium falciparum malaria.
abstract: Antibody titers and lymphocyte responses to synthetic peptides corresponding to repeated amino acid sequences of the 3' and 5' regions of Pf155/ring-infected erythrocyte surface antigen (RESA) were studied in two groups of Thai subjects, soldiers (Rangers), and villagers who differed in their history of malaria exposure. The frequency of Pf155/RESA seropositivity was similar in the two groups while the frequency of high titer antibody was significantly greater in villagers than in Rangers. Lymphocyte responsiveness in vitro to all Pf155/RESA peptides was infrequent for both groups although half of the subjects studied responded to crude Plasmodium falciparum asexual blood stage malaria antigen (MA). Among responders, Pf155/RESA peptides elicited lymphocyte responses in which proliferation and interferon-gamma (IFN-gamma) production were not associated, whereas with MA, the two responses were associated. The MA-stimulated lymphocyte proliferation and IFN-gamma production for both groups of volunteers appeared to be independent of antibody titer. In this study, antibody, but not lymphocyte, responses to Pf155/RESA peptides were shown to reflect differences in prior exposure and levels of acquired immunity to falciparum malaria.
authors.affiliation: Department of Pathobiology, Faculty of Science, Mahidol University, Bangkok, Thailand.
authors.forename: R
authors.initials: R
authors.lastname: Udomsangpetch
authors.forename: M
authors.initials: M
authors.lastname: Troye-Blomberg
authors.forename: A E
authors.initials: AE
authors.lastname: Brown
authors.forename: S
authors.initials: S
authors.lastname: Thaithong
authors.forename: P
authors.initials: P
authors.lastname: Perlmann
authors.forename: H K
authors.initials: HK
authors.lastname: Webster
mesh_terms: D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000096:biosynthesis; D000953:Antigens, Protozoan / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000276:immunology*; D016778:Malaria, Falciparum / Q000276:immunology*; D008875:Middle Aged; D008889:Military Personnel; D010963:Plasmodium falciparum / Q000276:immunology*; D015800:Protozoan Proteins / Q000276:immunology*; D013785:Thailand
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D000954:Antigens, Surface; D015800:Protozoan Proteins; C050256:ring-infected erythrocyte surface antigen (RESA), Plasmodium falciparum; D007371:Interferon-gamma