V Gamma V Delta 2 T-Cell Polyfunctionality Is Differently Modulated In Haart-Treated Hiv Patients According To Cd4 T-Cell Count

Alteration of gamma delta T-cell distribution and function in peripheral blood is among the earliest defects during HIV-infection. We asked whether the polyfunctional response could also be affected, and how this impairment could be associated to CD4 T-cell count. To this aim, we performed a cross-sectional study on HIV-infected individuals. In order to evaluate the poly-functional- V gamma 9V delta 2 T-cell response after phosphoantigen-stimulation, we assessed the cytokine/chemokine production and cytotoxicity by flow-cytometry in HAART-treated-HIV+ persons and healthy-donors. During HIV-infection V gamma 9V delta 2-polyfunctional response quality is affected, since several V gamma 9V delta 2 T-cell subsets resulted significantly lower in HIV+ patients in respect to healthy donors. Interestingly, we found a weak positive correlation between V gamma 9V delta 2 T-cell-response and CD4 T-cell counts. By dividing the HIV+ patients according to CD4 T-cell count, we found that Low-CD4 patients expressed a lower number of two V gamma 9V delta 2 T-cell subsets expressing MIP-1 beta in different combinations with other molecules (CD107a/IFN gamma.) in respect to High-CD4 individuals. Our results show that the V gamma 9V delta 2 T-cell- response quality in Low-CD4 patients is specifically affected, suggesting a direct link between innate V gamma 9V delta 2 T-cells and CD4 T-cell count. These findings suggest that V gamma 9V delta 2 T-cell quality may be indirectly influenced by HAART therapy and could be included in a new therapeutical strategy which would perform an important role in fighting HIV infection.