Molecular mechanism underlying natural killer cell differentiation and acquisition of target recognition

自然杀伤（NK）细胞是一小部分白色血细胞，为我们提供了抵御多种微生物、病毒和异常肿瘤细胞的第一道防线。 NK细胞功能的活化通过细胞表面上两组NK受体（活化和抑制性受体）的同时接合的信号传导平衡来控制。存在一个多步骤的发育过程，将骨髓干细胞转化为这些专门的NK细胞。 重要的是，NK细胞在发育过程中被训练以区分自身和非自身细胞。 后者在防止成熟NK细胞攻击自身组织方面很重要。 参与这一发展过程的因素和潜在机制在很大程度上仍不清楚。 这部分是由于在基因工程的主要NK细胞的困难，并缺乏实验系统，使我们能够表征蛋白质的功能，在特定的NK成熟状态。

Natural Killer (NK) cells are a small population of white blood cells that provide us a first line of defense against many types of microorganisms, viruses, and abnormal tumor cells. Activation of NK cell functions is controlled by a balance of signaling through simultaneous engagement of two groups of NK receptors (activation and inhibitory receptors) on the cell surface. There exists a multiple-step, developmental process that turns bone marrow stem cells into these specialized NK cells. Importantly, NK cells are educated to distinguish self and non-self cells during development. The latter is important in preventing mature NK cells from attacking self-tissues. The factors and the underlying mechanism involved in this developmental process remain largely unclear. This is in part due to difficulty in genetically engineering primary NK cells, and lack of experimental systems that allow us to characterize a protein's function in specific NK maturation states.