NK cells from individuals with PBC, but not from HFe patients or HC, responded to 0.005 ng/ml IL-12 with an increase in IFNγ expression from 1.1% at rest to 2.9% (p < 0.001) and produced greater quantities of IFNγ compared to HFe patients (2.9 vs. 1.2%, p < 0.02) and HC (2.9 vs. 0.4%, p < 0.001; Figures 4A,B). Here, IFNG is linked to primary biliary cholangitis.