DETECTION OF CD8 T-CELL EXPANSIONS WITH RESTRICTED T-CELL RECEPTOR-V GENE USAGE IN INFANTS VERTICALLY INFECTED BY HIV-1

Objective: To investigate the T-cell receptor (TCR) repertoire usage i n infants born to mothers infected with HIV-1 in order to discern poss ible perturbations in TCR usage as a consequence of HIV-1 infection. D esign: Blood samples from five HIV-1-infected and six non-infected chi ldren horn to HIV-1-seropositive mothers were collected at two to thre e timepoints during the first and second year of life and the TCR vari able gene usage was determined. Methods: Triple staining flow cytometr y analysis using a panel of monoclonal antibodies (MAb) to TCR V alpha and V beta gene products and antibodies to CD4 and CD8 was performed. Results: Frequent large expansions of CD8+ lymphocyte subpopulations bearing distinct V alpha and V beta gene products was seen in HIV-1-in fected children (four out of five) but was rarely detected in uninfect ed children. Conclusion: The study demonstrated the frequent occurrenc e of persistent and clonal expansions of CD8+ T cells bearing distinct V alpha/V beta gene products in some HIV-1 vertically infected infant s similar to those observed during primary infection in adults.