Tuberculosis antigen-specific T cell responses during the first 6 months of antiretroviral treatment.

The reconstitution of Mycobacterium tuberculosis (Mtb)-antigen-specific CD4 T cells in a cohort of HIV-infected persons starting antiretroviral treatment (ART) in high TB endemic area is described. Restoration of the antigen-specific CD4 T cell subsets mirrored the overall CD4 T cell compartment. Activation (assessed by HLA-DR expression) decreased during ART but remained elevated compared to HIV-uninfected persons. Despite known Mtb sensitisation determined by IGRA, 12/23 participants had no Mtb-specific CD4 T cells detectable by flow cytometry, combined with overall elevated T cell activation and memory differentiation, suggesting heightened turnover. Our data suggest early ART initiation to maintain polyfunctional immune memory responses.