FIGURE 2.

Role of T-bet in NK cell development and function in mice. (A) T-bet-deficient mice have low NK cell numbers in the spleen, liver, and peripheral blood with accumulation of NK cells in LNs and BM. (B) NK cells from T-bet-deficient mice have an immature phenotype, expression of α_v integrin and ckit, and high levels of CD69. T-bet^{– / –} NK cells undergo rapid apoptosis and have decreased longevity in addition to impaired cytotoxicity and low IFN-γ production. (C) Different TFs regulate T-bet, among these, Ets-1, Gata-3, Mef, and Pu.1. T-bet represses CD27 expression in mature NK cells and negatively regulates S1P5.