Immune repopulation after HAART in previously untreated HIV-1-infected children. Paediatric European Network for Treatment of AIDS (PENTA) Steering Committee.

In 25 vertically HIV-infected children receiving highly-active antiretroviral therapy, a 3-log10 reduction in plasma HIV RNA load was maintained for 1 year and was associated with a doubling of the CD4-cell percentage. Most (75%) new CD4 cells carried the CD45RA marker of naive cells and there was only a small rise in memory cells (CD45RO). This pattern of immune restoration differs from adults, and may be due to the presence of a functioning thymus in children.