Given that HIV infection is associated with upregulation of inhibitory receptors on CD4 T cells, and that the risk of developing active TB disease is more than 20-fold higher in HIV-infected individuals, compared with HIV-uninfected individuals (1, 3), we sought to determine if inhibitory receptors are upregulated on Mtb-specific CD4 T cells in individuals co-infected with Mtb and HIV, which may ultimately contribute to impairment of Mtb-specific CD4 T cell functional capacity and progression to active TB disease. The gene discussed is CD4; the disease is HIV infectious disease.