CD28 and tuberculosis: Inflammatory factors, including IFN‐γ, Interleukin‐17A, and Interleukin‐6, were negatively correlated with CD3 + CD4 + T cell count, CD3 + CD4 + CD28+ T cell count, MM of CD3 + CD8+ T cell, CD3 + CD8 + CD28+ T cell count and MM of CD3 + CD8+ T cell but positively correlated with MMP‐low% of CD3 + CD8 + CD28+ T cells in HIV‐TB patients.