凋亡细胞清除过程中相关信号及机制的研究进展

Research progress of relevant signals and mechanisms in clearance of apoptosis cells

机体中每时每刻都有大量的凋亡细胞产生,及时清除这些凋亡细胞对于维持机体的免疫平衡至关重要。在凋亡细胞的清除中,巨噬细胞发挥主要作用,其清除过程分为3个阶段:招募,识别,吞噬。招募阶段,凋亡细胞会分泌"find me"信号,吞噬细胞则会做出响应然后被招募到凋亡细胞处。识别阶段,凋亡细胞表面的"eat-me"信号与吞噬细胞表面的吞噬受体相互识别结合。吞噬阶段,"eat-me"信号向吞噬细胞内传导信号,例如激活GTPase Rac1,引起肌动蛋白聚合和细胞骨架的重排,促进对凋亡细胞的吞噬。若凋亡细胞的清除机制出现障碍,未被及时清除的凋亡细胞将进入次级坏死状态而释放胞内的自身抗原。这些自身抗原可能刺激机体免疫活化而产生自身抗体,进而引发自身免疫性疾病如SLE。本文就吞噬细胞对凋亡细胞清除机制的研究进展作详细综述。

Our bodies produce a lot of apoptotic cells every day,and the timely removal of these apoptotic cells is essential to maintain the immune balance of the body.In the removal of apoptotic cells,macrophages play a major role,and their removal process is divided into three stages：recruitment,identification and phagocytosis.In the recruitment stage,apoptotic cells secrete ＇find me＇ signals,and phagocytes respond and are recruited to apoptotic cells.At the identification stage,the ＇eat-me＇ signal of apoptotic cells was identified with the phagocytic receptor on the surface of phagocytes.Phagocytic phase,the ＇ eat-me＇ signal transmits signals to macrophages,such as activating the small GTPase Rac1,which leads to actin polymerization and cytoskeleton rearrangement to promote the phagocytosis of apoptotic cells.If the removal mechanism of apoptotic cells is obstructive,the apoptotic cells that have not been cleared in time will enter the secondary necrotic state and release the self-antigens.These self-antigens may stimulate the body＇s immune system to produce autoantibodies,leading to autoimmune diseases such as SLE.The research progress of the macrophage on the removal mechanism of apoptosis cells is reviewed in this paper.