Njai H. F. auteur aut IRD Gali Y. auteur aut IRD Vanham G. auteur aut IRD Clybergh C. auteur aut IRD Jennes W. auteur aut IRD Vidal Nicole auteur aut IRD Butel Christelle auteur aut IRD Mpoudi Ngolé E. auteur aut IRD Peeters Martine auteur aut IRD Arien K. K. auteur aut IRD text journalArticle eng text/pdf reformatted digital access Background: CRF02_AG is the predominant HIV strain circulating in West and West Central Africa. The aim of this study was to test whether this predominance is associated with a higher in vitro replicative fitness relative to parental subtype A and G viruses. Primary HIV-I isolates (10 CRF02_AG, 5 subtype A and 5 subtype G) were obtained from a well-described Cameroonian cohort. Growth competition experiments were carried out at equal multiplicity of infection in activated T cells and monocyte-derived dendritic cells (MO-DC) in parallel. Results: Dual infection/ competition experiments in activated T cells clearly indicated that CRF02_AG isolates had a significant replication advantage over the subtype A and subtype G viruses. The higher fitness of CRF02_AG was evident for isolates from patients with CD4+ T cell counts > 200 cells/mu L (non-AIDS) or CD4+ T cell counts < 200 cells/mu L (AIDS), and was independent of the co-receptor tropism. In MO-DC cultures, CRF02_AG isolates showed a slightly but not significantly higher replication advantage compared to subtype A or G isolates. Conclusion: We observed a higher ex vivo replicative fitness of CRF02_AG isolates compared to subtype A and G viruses from the same geographic region and showed that this was independent of the co-receptor tropism and irrespective of high or low CD4+ T cell count. This advantage in replicative fitness may contribute to the dominant spread of CRF02_AG over A and G subtypes in West and West Central Africa. specialized 052 3 art. no. 40 - NIL_1-NIL_11 2006 1742-4690 https://www.documentation.ird.fr/hor/fdi:010035770 10.1186/1742-4690-3-40 1742-4690 [F B010035770] https://www.documentation.ird.fr/hor/fdi:010035770 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/2025-01/010035770.pdf IRD - Base Horizon / Pleins textes 2006-10-06 2025-01-03 fdi:010035770 fre