Chetty, ShivanGovender, PamlaZupkosky, JenniferPillay, MonaGhebremichael, MusieMoosa, Mahomed-Yunus S.Ndung’u, ThumbiPorichis, FilipposKasprowicz, Victoria O.Paxton, William A.2019-10-132015Chetty, Shivan, Pamla Govender, Jennifer Zupkosky, Mona Pillay, Musie Ghebremichael, Mahomed-Yunus S. Moosa, Thumbi Ndung’u, Filippos Porichis, and Victoria O. Kasprowicz. 2015. “Co-Infection with Mycobacterium Tuberculosis Impairs HIV-Specific CD8+ and CD4+ T Cell Functionality.” Edited by William A Paxton. PLOS ONE 10 (3): e0118654. doi:10.1371/journal.pone.0118654.1932-6203http://nrs.harvard.edu/urn-3:HUL.InstRepos:41542737The ability of antigen-specific T cells to simultaneously produce multiple cytokines is thought to correlate with the functional capacity and efficacy of T cells. These 'polyfunctional' T cells have been associated with control of HIV. We aimed to assess the impact of co-infection with Mycobacterium tuberculosis (MTB) on HIV-specific CD8+ and CD4+ T cell function. We assessed T cell functionality in 34 South African adults by investigating the IFN-gamma, IL-2, TNF-alpha, IL-21 and IL-17 cytokine secretion capacity, using polychromatic flow cytometry, following HIV Gag-specific stimulation of peripheral blood mononuclear cells. We show that MTB is associated with lower HIV-specific T cell function in co-infected as compared to HIV mono-infected individuals. This decline in function was greatest in co-infection with active Tuberculosis (TB) compared to co-infection with latent MTB (LTBI), suggesting that mycobacterial load may contribute to this loss of function. The described impact of MTB on HIV-specific T cell function may be a mechanism for increased HIV disease progression in co-infected subjects as functionally impaired T cells may be less able to control HIV.en-USJournal Article2019-10-1310.1371/journal.pone.0118654