Flow cytometry evaluation of the T-cell receptor Vβ repertoire among HIV-1 infected individuals before and after antiretroviral therapy

HIV-1 infection leads to serious impairment of the immune system and perturbations in the T cell receptor V beta repertoire are also described. Immune reconstitution can be potentially achieved in response to HAART. In the present study 10 patients were investigated for the V beta pattern expression before and after six months of HAART. TCR were analyzed for T CD4+ and CD8+ subsets, separately, by flow cytometry, using a monoclonal antibody set of 24 different V beta chains. Compared to eight Brazilian healthy controls, no differences in V beta pattern of expression was observed for patients before or on antiretroviral therapy. Some chains such as V beta 3, 14, 16, 20 and 21.3 were over utilized by both T subsets, independently of HIV infection and/or antiretroviral treatment, differing from the ones described for individuals of other nationalities. However, when each patient was taken individually, particular alterations were detected for the V beta gene usage, compared to controls, for all individuals. After treatment, significant V beta usage changes were observed for seven patients. One or more chains on both T subsets were engaged in this process, defining a preferential oligoclonal profile for TCR repertoire distribution, after HAART. Although no pattern of specific V beta changes was detected in the circulating T cells, we cannot exclude that differential immune responses to HIV or other important antigens are being focused by these cells.