期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1991
卷号:88
期号:5
页码:1751-1755
DOI:10.1073/pnas.88.5.1751
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Antigens associated with the surface of merozoites of the malaria parasite Plasmodium falciparum are directly accessible to immune attack and therefore are prime vaccine candidates. We have previously shown that one of the two known merozoite surface antigens (merozoite surface antigen 2; MSA-2) exhibits considerable sequence and antigenic diversity in different isolates. The sequences of MSA-2 from three isolates revealed a central domain composed of repeats that vary in number, length, and sequence, flanked in turn by nonrepetitive variable sequences and by conserved N- and C-terminal domains. We report here the sequences of a further four MSA-2 alleles, containing repetitive sequences that are related but not identical to each other. The seven alleles of MSA-2 can be divided into two distinct allele families on the basis of nonrepetitive sequences. Hybridization studies with repeat probes indicated that all of the 44 P. falciparum isolates examined contained repeat regions similar to those defined in known MSA-2 sequences.