Based on in vitro studies that have shown NK cells lyse TB-infected monocytes and macrophages, and generate significant amounts of IFN-γ when exposed to these infected phagocytes (Vankayalapati et al., 2002, Vankayalapati et al., 2005), NK cells are thought to be involved in the immune response against this intracellular bacterium. Here, IFNG is linked to tuberculosis.