Mycobacterium tuberculosis-specific cytokine responses according to HIV status among household contacts of people with TB

Abstract

Following exposure to Mycobacterium tuberculosis (Mtb), a coordinated host response comprising both pro- and anti-inflammatory cytokines is critical for pathogen control. Although tuberculosis (TB) remains the leading cause of death among people with human immunodeficiency virus (HIV), the impact of HIV infection on Mtb-specific immune responses remains unclear. In this cross-sectional study of TB-exposed household contacts with and without HIV, we collected remaining supernatant from interferon-gamma release assay (IGRA) testing (QuantiFERON-TB Gold Plus [QFT-Plus]) and measured Mtb-specific pro-inflammatory, anti-inflammatory, and regulatory cytokine responses with a multiplex assay of 11 analytes. While people with HIV had lower responses to mitogen stimulation for some cytokines (granulocyte-macrophage colony-stimulating factor [GM-CSF], interleukin [IL]-2, IL-10, IL-17A, IL-22), there was no difference in cytokine levels for people with and without HIV following stimulation with Mtb-specific antigens. Future studies are necessary to explore whether changes in Mtb-specific cytokine responses over time are associated with distinct clinical outcomes following exposure to TB.

Keywords: Cytokines; HIV; Tuberculosis.