Binding antibody responses to the immunogenic regions of viral envelope in HIV-1-infected Indian children.

Limited information exists on the antibody responses elicited against the viral envelope in HIV-1-infected children. In this cross-sectional study, we assessed the antibody responses against three different immunogenic regions of HIV-1 envelope, namely V3 region of gp120, membrane proximal external region (MPER), and immunodominant loop (IDL) of gp41 in HIV-1-infected children from north India. We recruited 75 HIV-1-infected (40 antiretroviral naive and 35 treated) children, with age ranging from 1.5 to 16 y. Antibodies to V3 and the IDL region were found in a majority of the infected children, whereas antibodies to MPER were found in approximately one-third of the children studied. Higher antibody titers to the immunogenic regions corresponded to the symptomatic stages of HIV-1 infection in both naive and antiretroviral therapy (ART)-treated children. High titers of anti-V3C and anti-IDL antibodies were observed in a subset of antiretroviral-naive patients with suppressed viremia (<47 RNA copies/mL), suggesting that antibodies to these immunogenic regions are present regardless of their viremic status. Further, the antibody titers were significantly lower in the plasma of treated patients compared to naive patients, regardless of whether they were virologically suppressed or not. This is the first report on the antibody responses elicited in HIV-1-infected children in India. The study may help to understand the humoral antibody responses directed against viral envelope in HIV-1-infected children.