Population structure of the genes encoding the polymorphic Plasmodium falciparum apical membrane antigen 1: Implications for vaccine design

Authors

Junhui Duan, National Institute of Allergy and Infectious Diseases (NIAID)
Jianbing Mu, National Institute of Allergy and Infectious Diseases (NIAID)
Mahamadou Ali Thera, University of Bamako
Deirdre Joy, National Institute of Allergy and Infectious Diseases (NIAID)
Sergei L.Kosakovsky Pond, University of California, San Diego
David Diemert, National Institute of Allergy and Infectious Diseases (NIAID)
Carole Long, National Institute of Allergy and Infectious Diseases (NIAID)
Hong Zhou, National Institute of Allergy and Infectious Diseases (NIAID)
Kazutoyo Miura, National Institute of Allergy and Infectious Diseases (NIAID)
Amed Ouattara, University of Bamako
Amagana Dolo, University of Bamako
Ogobara Doumbo, University of Bamako
Xin Zhuan Su, National Institute of Allergy and Infectious Diseases (NIAID)
Louis Miller, National Institute of Allergy and Infectious Diseases (NIAID)

Document Type

Journal Article

Publication Date

6-3-2008

Journal

Proceedings of the National Academy of Sciences of the United States of America

Volume

105

Issue

22

DOI

10.1073/pnas.0802328105

Abstract

Immunization with the highly polymorphic Plasmodium falciparum apical membrane antigen 1 (PfAMA1) induces protection in animals but primarily against parasites that express the same or similar alleles. One strategy to overcome the obstacle of polymorphism is to combine PfAMA1 proteins representing major haplotypes into one vaccine. To determine the minimum number of haplotypes that would confer broad protection, we sequenced the coding region of PfAMA1 from 97 clones from around the world and 61 isolates from Mali, identifying 150 haplotypes for domains 1 to 3 that included previous sequences. A clustering algorithm grouped the 150 haplotypes into six populations that were independent of geographic location. Each of the six populations contained haplotypes predominantly of that population (predominant haplotypes) and haplotypes that were a mixture of haplotypes represented in other populations (admixed haplotypes). To determine the biological relevance of the populations identified through the clustering algorithm, antibodies induced against one predominant haplotype of population 1 (3D7) and one admixed haplotype of population 5 (FVO) were tested for their ability to block parasite invasion of erythrocytes. Parasites expressing PfAMA1s belonging to population 1 were efficiently inhibited by 3D7-specific antibodies, whereas parasites expressing PfAMA1s belonging to other populations were not. For FVO-specific antibodies, we observed growth inhibition against itself as well as isolates belonging to populations 3 and 6. Our data suggests that the inclusion of PfAMA1 sequences from each of the six populations may result in a vaccine that induces protective immunity against a broad range of malaria parasites. © 2008 by The National Academy of Sciences of the USA.

APA Citation

Duan, J., Mu, J., Thera, M., Joy, D., Pond, S., Diemert, D., Long, C., Zhou, H., Miura, K., Ouattara, A., Dolo, A., Doumbo, O., Su, X., & Miller, L. (2008). Population structure of the genes encoding the polymorphic Plasmodium falciparum apical membrane antigen 1: Implications for vaccine design. Proceedings of the National Academy of Sciences of the United States of America, 105 (22). http://dx.doi.org/10.1073/pnas.0802328105