Day K. P., Artzy-Randrup Y., Tiedje K. E., Rougeron V., Chen D. S., Rask T. S., Rorick M. M., Migot Nabias Florence, Deloron Philippe, Luty Adrian, Pascual M. (2017). Evidence of strain structure in Plasmodium falciparum var gene repertoires in children from Gabon, West Africa. Proceedings of the National Academy of Sciences of the United States of America, 114 (20), p. E4103-E4111. ISSN 0027-8424.
Titre du document
Evidence of strain structure in Plasmodium falciparum var gene repertoires in children from Gabon, West Africa
Année de publication
2017
Auteurs
Day K. P., Artzy-Randrup Y., Tiedje K. E., Rougeron V., Chen D. S., Rask T. S., Rorick M. M., Migot Nabias Florence, Deloron Philippe, Luty Adrian, Pascual M.
Source
Proceedings of the National Academy of Sciences of the United States of America, 2017,
114 (20), p. E4103-E4111 ISSN 0027-8424
Existing theory on competition for hosts between pathogen strains has proposed that immune selection can lead to the maintenance of strain structure consisting of discrete, weakly overlapping antigenic repertoires. This prediction of strain theory has conceptual overlap with fundamental ideas in ecology on niche partitioning and limiting similarity between coexisting species in an ecosystem, which oppose the hypothesis of neutral coexistence. For Plasmodium falciparum, strain theory has been specifically proposed in relation to the major surface antigen of the blood stage, known as PfEMP1 and encoded by the multicopy multigene family known as the var genes. Deep sampling of the DBLa domain of var genes in the local population of Bakoumba, West Africa, was completed to define whether patterns of repertoire overlap support a role of immune selection under the opposing force of high outcrossing, a characteristic of areas of intense malaria transmission. Using a 454 high-throughput sequencing protocol, we report extremely high diversity of the DBLa domain and a large parasite population with DBLa repertoires structured into nonrandom patterns of overlap. Such population structure, significant for the high diversity of var genes that compose it at a local level, supports the existence of "strains" characterized by distinct var gene repertoires. Nonneutral, frequency-dependent competition would be at play and could underlie these patterns. With a computational experiment that simulates an intervention similar to mass drug administration, we argue that the observed repertoire structure matters for the antigenic var diversity of the parasite population remaining after intervention.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020]
;
Entomologie médicale / Parasitologie / Virologie [052]
Description Géographique
GABON
Localisation
Fonds IRD [F B010070061]
Identifiant IRD
fdi:010070061
