Thus, specific phosphoantigen/IL2 immune stimulation early during Mtb infection rapidly expands and differentiates Vγ2Vδ2 T cells into multi-functional effector cells capable of mounting anti-TB IFNγ response, inhibiting Mtb growth through in vivo or constitutive production of perforin/granulysin, and producing IL-12 and promoting pulmonary Th1 responses of peptide-specific CD4+ and CD8+ T cells. The gene discussed is CD4; the disease is tuberculosis.