CD4 and tuberculosis: It is also worth to mention that anti-TB cytokines produced by the CD4+CD161+T-cell subset can certainly contribute to protective immunity against very early Mtb infection as seen in NHP and human resisters (16, 19), while only perforin and IFN-γ are required for the ability of CD4+CD161+T-cells to inhibit the growth of intracellular mycobacteria.