Regarding TG Rickettsia, although enhanced NK cell activity has also been reported during early rickettsia infection, the contribution of NK cells to a relevant production of IFN-γ has been questioned by the observation of unaltered IFN-γ release after NK cell depletion in mice, suggesting that other cell sources may sustain IFN-γ production (i.e. tissue macrophages) [73]. The gene discussed is IFNG; the disease is Rickettsiosis.