Tuberculosis patients display a high proportion of CD8 T cells with a high cytotoxic potential.

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) and remains a major cause of morbidity and mortality worldwide. In the host's immune response system, T cells play a critical role in mediating protection against Mtb infection, but the role of CD8 T cells is still controversial. We evaluated the phenotypical characterization and cytotoxic ability of CD8 T cells by flow cytometry-based assay.