IFNG and arthritic joint disease: In arthritis, for example, IFN-γ: (i) inhibits neutrophil trafficking [7], (ii) promotes regulatory T-cell function [42], (iii) suppresses Th17 cell expansion [43], thereby attenuating inflammation and preventing T-cell driven osteoclast activation and bone erosion [44] and (iv) limits the biological activity of interleukin-18 [45].