Cytotoxic T lymphocyte responses in the peripheral blood of children born to human immunodeficiency virus-1-infected mothers.

Cytotoxic T lymphocytes (CTL) are present at high activities in adult patients infected with the human immunodeficiency virus (HIV). In this report, CTL effectors were identified in peripheral blood mononuclear cells (PBMC) of children born to HIV-1-infected mothers. These CTL killed HLA-matched HIV-1-infected H9 target cells or doubly transfected P815-A2-env, gag or nef mouse tumor cells, which expressed the viral antigens in association with HLA-A1/A3 or HLA-A2, respectively. HIV-1-specific CTL were detected early after birth (less than 2 months) and remained present during the asymptomatic phase of the infection. As in HIV-1-infected adults, HIV-specific CTL declined with disease progression. Surprisingly, HIV-1-specific CTL were detected in the PBMC of three children who subsequently became seronegative.