HIV Infection Functionally Impairs Mycobacterium tuberculosis-Specific CD4 and CD8 T-Cell Responses

Mycobacterium tuberculosis and human immunodeficiency virus (HIV) infections are coendemic in several regions of the world, and M. tuberculosis /HIV-coinfected individuals are more susceptible to progression to tuberculosis disease. We therefore hypothesized that HIV infection would potentially impair M. tuberculosis -specific protective immunity in individuals suffering from latent tuberculosis infection (LTBI) or active pulmonary tuberculosis (PTB). In this study, we demonstrated that M. tuberculosis /HIV-coinfected individuals have fewer circulating M. tuberculosis -specific CD4 T cells and that those that remained were functionally impaired in both LTBI and PTB settings. In addition, we showed that HIV infection significantly interferes with M. tuberculosis -induced systemic proinflammatory cytokine/chemokine responses. Taken together, these data suggest that HIV infection impairs functionally favorable M. tuberculosis -specific immunity.