IFNG and tuberculosis: Untreated active TB patients had a significantly higher proportion of ESAT-6/CFP-10 specific IFN-γ only-secreting T cells and a significantly lower proportion of ESAT-6/CFP-10 specific IFN-γ/IL-2-secreting and IL-2 only-secreting T cells than persons with untreated LTBI (figures 5a, b, c, d, p = 0.02, p = 0.04 and p = 0.03 respectively).