HIGH-FREQUENCY OF GAG-SPECIFIC AND ENVELOPE-SPECIFIC CYTOTOXIC T-LYMPHOCYTE PRECURSORS IN CHILDREN WITH VERTICALLY ACQUIRED HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 INFECTION

Circulating human immunodeficiency virus type 1 (HIV-1)-specific cytot oxic T lymphocytes (CTL) are seen less frequently in unstimulated peri pheral blood mononuclear cells (PBMC) from children with vertically ac quired HIV infection than in PBMC from HIV-infected adults. HIV-1 Gag- , reverse transcriptase (RT)-, and envelope (Env)-specific cytotoxic a ctivity was studied in PBMC from HIV-infected children. Only 9% of sub jects had Gag- or RT-specific CTL in unstimulated PBMC. However, in PB MC studied after CD3 stimulation, Gag- and Env-specific CTL were found in PBMC from 98% and 78% of HIV-infected children, respectively. Limi ting dilution analysis of precursor CTL (pCTL) frequencies in PBMC fro m children > 12 months old demonstrated Gag-and Env-specific pCTL freq uencies from 0.5 to 6.3/10,000 PBMC and from 0.66 to 33.0/10,000 PBMC, respectively. Thus, children with vertically acquired HIV infection h ave high frequencies of HIV-specific pCTL.