Migration of NK cells

NK cells were initially thought to be endowed with a particular migratory pattern and to mainly circulate in the blood. The recent findings reviewed here highlight that NK cells can exhibit different predilictions for tissue compartments, i.e., lymph nodes, inflamed tissues, etc., where they can play an important role as active participants in directing DC maturation and T cell response polarization and/or as cytotoxic effector cells. The mechanisms regulating tissue-selective NK cell homing and functional specialization are just starting to be unraveled, but the importance of tissue microenvironment is becoming increasingly clear. An example is given by decidual NK cells whose differentiation, accumulation and functional program are under hormonal influence.