Recovery of replication-competent virus from CD4 T cell reservoirs and change in coreceptor use in human immunodeficiency virus type 1-infected children responding to highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) suppresses plasma viremia in most patients with human immunodeficiency virus (HIV) infection. Prospective study of HIV-infected children (n = 27) shows that, in 8 of 12 who responded to HAART (greater than or equal to 0.5 log reduction in plasma HIV RNA), HAART restricted the number of coreceptors used by the predominant HIV isolate (mean number of coreceptors used at baseline was 4, vs. 1 coreceptor used at 6 months after treatment). This decrease was most striking in 6 of 8 children whose HIV coreceptor tropism changed from X4-tropic at baseline to R5-tropic. In 6 of 10 children tested, with plasma HIV RNA levels of <50 copies/mL, R5-tropic virus was isolated from CD4 T cell reservoirs. All the responding children had a significant increase in naive CD4 T cells (P < .05). These results show that persistent HIV T cell reservoirs are present in children and that HAART may influence the number and type of coreceptors used by the predominant virus isolate.