Alteration in CD29high CD4+ lymphocyte subset is a common feature of early HIV disease and of active tuberculosis

Abstract

Peripheral CD4 T-cell depletion has been observed in human immunodeficiency virus (HIV)-negative patients with pulmonary tuberculosis (TB). To investigate more accurately this alteration, we studied peripheral blood CD45RA+ and CD29high CD4 subsets in 79 TB patients with (HIV+TB+) or without (HIV-TB+) HIV infection, 85 HIV-infected patients without TB (HIV+TB-), and 43 healthy controls, all living in West Africa. The high proportion of CD4+CD29high T cells observed in controls was dramatically decreased in CDC-A stage HIV+TB- patients. CD45RA+ CD4+ T cells were depleted during the CDC-B stage. Both the percentage and the absolute count of CD29highCD4+ T cells were decreased in HIV-TB+ and HIV+TB+ patients versus controls, but CD45RA+CD4+ T cells were not decreased in TB patients without HIV-infection. Although distinct alterations in the CD4+ T-cell homeostasis are involved in TB-versus HIV-infected subjects, our data suggest that the CD29+CD4+ T-cell depletion observed during the early HIV disease contributes to the risk of active TB, by reducing the pool of T cells able to relocalize to the sites of the M. tuberculosis multiplication.