IDO2 and tuberculosis: While earlier introduction of combinatorial antiretroviral therapy (cART) significantly reduced the recruitment of myeloid cells expressing immunoregulatory proteins like indoleamine 2,3, dioxygenase (IDO) to the lung granulomas, facilitated T cell reconstitution, and better controlled TB reactivation (2), as opposed to late cART (3), chronic immune activation was not completely mitigated.