Correlation between HIV-Specific CD8 cell production of interferon-γ and plasma levels of HIV RNA in perinatally infected pediatric populations

Background. CD8 cell responses to human immunodeficiency virus (HIV) have been correlated with virus control in adults, and this study outcome has been controversial. Attempts to establish the same correlation in small numbers of children have also been made, with similar controversy resulting. Methods. A total of 110 perinatally infected children were studied. Nine of the children (mean age, 1.9 years vs. 11.8 years for the remaining 101 children) received treatment with anti-retrovirals within the first 3 months of life. CD4 cell and HIV RNA levels were measured. Production of interferon-gamma after exposure to recombinant vaccinia vectors was measured by enzyme-linked immunospot (ELISPOT) assay. Results. Responses to Pol and Gag antigens exceeded those to Nef and Env antigens, with responses significantly approximated by a quadratic function for which peak responses occurred at plasma HIV RNA levels of 10(3)-10(4) HIV RNA copies/mL. Children who are treated early in life with highly active antiretroviral therapy have fewer total responses of ELISPOT-forming cells to HIV antigens than do children who are treated later in life.