Louis SchofieldSavanat TharavanijAllan SaulVirgilio Do RosarioChev KidsonQIMR Berghofer Medical Research InstituteMahidol UniversityInstituto Evandro ChagasThe University of North Carolina at Chapel Hill2018-10-122018-10-121985-01-01Transactions of the Royal Society of Tropical Medicine and Hygiene. Vol.79, No.4 (1985), 493-49418783503003592032-s2.0-0022294170https://repository.li.mahidol.ac.th/handle/20.500.14594/30794The expression by Plasmodium falciparum of a specific S-antigen has been examined in primary isolates in different regions of the world using a monoclonal antibody that recognizes an epitope within a known repeated amino acid sequence. The epitope was expressed by a small proportion of primary isolates in each of Brazil, Thailand and Papua New Guinea, demonstrating that this S-antigen gene is widespread. The data are consistent with the possibility that the occurrence of P. falciparum strains expressing a particular S-antigen is periodic, related to the duration of immunity against that antigen in a given human population. © Oxford University Press.Mahidol UniversityImmunology and MicrobiologyMedicineArticleSCOPUS10.1016/0035-9203(85)90074-4