In the co-infection model utilized in this report, in which clinical isolates of both MTb and HIV-1 subtype C were used to infect freshly prepared human peripheral blood cells, we found that specific disruption of NFAT5 binding to the LTR significantly impaired viral replication during MTb co-infection, indicating that even the presence of three intact NF-κB binding sites, which is typical for HIV-1 subtype C isolates [30], cannot compensate for loss of NFAT5 recruitment to the viral LTR in the context of MTb co-infection. The gene discussed is NFAT5; the disease is coinfection.