Activation-Induced Marker Expression Identifies Mycobacterium tuberculosis-Specific CD4 T Cells in a Cytokine-Independent Manner in HIV-Infected Individuals with Latent Tuberculosis.
Morgan S BarhamWendy E WhatneyJeremiah KhayumbiJoshua OngaloLoren E SasserAngela P CampbellMeghan FranczekMbuyi Madeleine KabongoSamuel Gurrion OumaFelix Odhiambo HayaraNeel R GandhiCheryl L DayPublished in: ImmunoHorizons (2020)
HIV infection is a significant risk factor for reactivation of latent Mycobacterium tuberculosis infection (LTBI) and progression to active tuberculosis disease, yet the mechanisms whereby HIV impairs T cell immunity to M. tuberculosis have not been fully defined. Evaluation of M. tuberculosis-specific CD4 T cells is commonly based on IFN-γ production, yet increasing evidence indicates the immune response to M. tuberculosis is heterogeneous and encompasses IFN-γ-independent responses. We hypothesized that upregulation of surface activation-induced markers (AIM) would facilitate detection of human M. tuberculosis-specific CD4 T cells in a cytokine-independent manner in HIV-infected and HIV-uninfected individuals with LTBI. PBMCs from HIV-infected and HIV-uninfected adults in Kenya were stimulated with CFP-10 and ESAT-6 peptides and evaluated by flow cytometry for upregulation of the activation markers CD25, OX40, CD69, and CD40L. Although M. tuberculosis-specific IFN-γ and IL-2 production was dampened in HIV-infected individuals, M. tuberculosis-specific CD25+OX40+ and CD69+CD40L+ CD4 T cells were detectable in the AIM assay in both HIV-uninfected and HIV-infected individuals with LTBI. Importantly, the frequency of M. tuberculosis-specific AIM+ CD4 T cells was not directly impacted by HIV viral load or CD4 count, thus demonstrating the feasibility of AIM assays for analysis of M. tuberculosis-specific CD4 T cells across a spectrum of HIV infection states. These data indicate that AIM assays enable identification of M. tuberculosis-specific CD4 T cells in a cytokine-independent manner in HIV-uninfected and HIV-infected individuals with LTBI in a high-tuberculosis burden setting, thus facilitating studies to define novel T cell correlates of protection to M. tuberculosis and elucidate mechanisms of HIV-associated dysregulation of antimycobacterial immunity.
Keyphrases
- hiv infected
- antiretroviral therapy
- mycobacterium tuberculosis
- hiv aids
- human immunodeficiency virus
- hiv positive
- pulmonary tuberculosis
- poor prognosis
- adverse drug
- machine learning
- cell proliferation
- dna methylation
- emergency department
- hiv testing
- hepatitis c virus
- oxidative stress
- risk factors
- long non coding rna
- genome wide
- south africa
- nk cells
- single cell
- men who have sex with men