Alteration of T Cell Phenotypes in HIV‐Neurotuberculosis Coinfection

Background Neurotuberculosis is one of the commonest HIV associated opportunistic infections of the central nervous system in India. HIV‐TB coinfection may lead to altered frequencies of T cells, thereby influencing the course and progression of the disease. Methods We examined the frequencies of T cell subsets in HIV infected individuals with neurotuberculosis (HIV+nTB+) as compared to individuals with HIV associated systemic TB (HIV+sTB+), asymptomatic HIV (HIV+TB‐), non‐HIV neuro TB (HIV‐nTB+), non‐HIV systemic TB (HIV‐sTB+), and healthy controls (HIV‐TB‐). Activation and senescence profiles of CD4 and CD8 T cells and memory subsets in peripheral blood mononuclear cells were studied by flow cytometry. Results The significant observations among the T cell subsets in HIV+nTB+ were: (1) Naïve T cells : decreased CD4 T cells compared to HIV‐sTB+ ( P = 0.005); decreased CD8 T cells compared to HIV‐nTB+ and HIV‐TB‐ ( P ≤ 0.007), (2) Memory T cells : expanded CD4 TEMRA cells compared to HIV‐nTB+, HIV‐sTB+, and HIV‐TB‐ ( P ≤ 0.003); expanded CD8 TEMRA cells compared to HIV‐nTB+ and HIV‐TB‐ ( P ≤ 0.005), (3) Activated T cells : higher CD4 T cells compared to HIV‐nTB+, HIV‐sTB+, and HIV‐TB‐ ( P ≤ 0.004); higher CD8 T cells compared to HIV + TB‐, HIV‐nTB+, HIV‐sTB+, and HIV‐TB‐ ( P ≤ 0.001), and (4) Senescent T cells : increased CD8 T cells compared to HIV‐nTB+ and HIV‐TB‐ groups ( P = 0.000). Conclusions Increased activation compared to HIV+TB‐, HIV‐nTB+, HIV‐sTB+, and HIV‐TB‐ groups and increased senescence compared to HIV‐nTB+ and HIV‐TB‐ groups were observed in CD8 T cells in HIV+nTB+, suggesting that the frequencies of these T cell subsets are altered to a greater extent in these individuals. © 2018 International Clinical Cytometry Society