Association Between Peripheral gamma [delta] T-Cell Profile and Disease Progression in Individuals Infected With HIV-1 or HIV-2 in West Africa

Background: Human gammadelta (...) T cells play an important role in protective immunity in HIV-1 and simian immunodeficiency virus infection; their role in HIV-2 infection is unknown. To determine the role of ... T cells in control of plasma viral load and CD4+ T-cell count in HIV-1 and HIV-2 infections in West Africa. Thirty HIV-1 and 25 HIV-2 treatment-naive chronically infected individuals, and 20 HIV-seronegative individuals from Senegal were studied using multiparametric flow cytometry to investigate the frequencies and phenotypes of peripheral ... T cells. ... T-cell parameters and correlates of HIV disease progression were assessed. We observed an expansion of V...1+ T-cell populations in both HIV-1 and HIV-2 infection. However, unlike HIV-1 infection, no significant contraction of the frequency of total V...2+ T cells was observed in HIV-2 infection. Significantly lower frequencies of CD4...V...2+ T cells were observed in HIV-2-infected individuals. Furthermore, frequencies of CD28-CD45RO+ and CD27-CD28-CD45RO- V...2+ T cell were low in HIV-1-infected individuals. V...2+ T-cell activation levels were elevated in both HIV-1-infected and HIV-2-infected individuals. The frequency of HLA-DR...CD38+-activated V...1+ and V...2+ T cells was associated with a decline in CD4+ T-cell counts and increased viral load in both HIV-1 and HIV-2 infection. Although maintaining the normal frequency of total V...2+ T cells, HIV-2 infection reduces the frequency of CD4+V...2+ T cells and alters the frequencies of subsets of V...1+ T cells. Both HIV-1 and HIV-2 infection induce ... T-cell activation, and this activation is associated with the disease progression. (ProQuest: ... denotes formulae/symbols omitted.)