中文摘要：

哺乳动物睾丸具有特殊的免疫环境来维持睾丸功能.睾丸细胞分泌多种免疫调节因子,参与调节睾丸免疫环境,免疫豁免与睾丸固有免疫应答可防止自身免疫反应及抵御微生物感染.当睾丸免疫平衡被破坏时,会引起睾丸炎,干扰精子发生,并可导致不育.多种免疫调控机制共同维持睾丸免疫平衡.近年来发现,Tyro3/Axl/Mer（TAM）受体酪氨酸激酶与模式识别受体在调节睾丸免疫环境中发挥重要作用,本文将综述相关的研究进展,提出有待深入研究的方向.

英文摘要：

Human infertility affects approximately 15% of couples at reproductive age worldwide. Male factors contribute up to 45% of infertility cases. Inflammatory conditions in the male genital system are responsible for about 10% of male infertility in developed countries, and the incidence of immunological infertility can be considerably higher in developing countries where medical cares and environment conditions are poor. In particular, immunological disorders in the testis freguently cause infertility because it is a organ where spermatogenesis carries out. The testis possesses a special immune environment because of its immunoprivileged status and innate immune system. Testicular immune privilege is essential for the protection of male germ cells from detrimental immune responses, whereas the local innate immune system plays a crucial role in the testicular defense against microbial infections. Most of testicular cells are involved in the regulation of testicular immune homeostasis. Disruption of testicular immune homeostasis may result in orchitis, one aetiological factor of male infertility. Multiple mechanisms cooperatively regulate testicular immune homeostasis. Recent studies have revealed important roles of Tyro3/Axl/Mer（TAM） receptor tyrosine kinases and pattern recognition receptors（PRRs） in regulating testicular immune environment. TAM receptors belong to one subfamily of receptor tyrosine kinases. The product of growth arrest-specific gene 6（Gas6） is common ligand of TAM receptors. TAM and Gas6 are expressed in the testis. TAM triple knockout mice are male sterile and develop autoimmune orchitis. TAM receptors regulate testicular immune homeostasis via three mechanisms：（i） PRR-initiated innate immune responses in Sertoli and Leydig cells are inhibited by TAM/Gas6 signaling, which reduce inflammatory cytokine production in the testis;（ii） TAM receptors promote phagocytosis of apoptotic germ cells by Sertoli cells. The phagocytic clearance of apoptotic germ cells by Sertoli cells can r