Liu Y, et al. - The prime focus of this research was to explore the general role of IL-22 in Mycobacterium tuberculosis infection. The findings suggested that IL-22 has various roles in tuberculosis immune responses. Membrane-bound IL-22+ T cells could play important roles in the human immune response to Mycobacterium.

Methods

• 156 subjects including 49 patients with pulmonary tuberculosis, 27 patients with tuberculous pleurisy (TPE), 38 people with latent tuberculous infection (LTBI) and 42 healthy controls (HC) were enrolled in this study.

Results

• The authors in this study found significantly higher IL-22 levels at the tuberculosis infection site than in the peripheral blood and higher antigen-specific IL-22 levels in the culture supernatant for patients with active tuberculosis than in healthy controls.
• They observed that the proportions of IL-22 + CD4+ T and IL-22 + CD8+ T cells in patients with active tuberculosis were significantly higher than those in the latent tuberculosis infection group and the healthy control group, based on intracellular cytokine staining.
• In addition, they found membrane-bound IL-22+ T cells, including CD4+ T cells and CD8+ T cells, by surface staining, particularly in patients with active tuberculosis.
• It was noted that the expression of membrane-bound IL-22 significantly diminished after drug therapy.