Complement proteins are ancient components of innate immunity that have emerged as crucial regulators of neural networks. We discuss these roles in the context of the CNS development, acute CNS viral infections, and post-infectious and noninfectious CNS disorders, with an emphasis on microglia-mediated loss of synapses. Despite extensive examples that implicate classical complement proteins and their receptors in CNS dysfunction, recent data suggest that they exert neuroprotective roles in CNS homeostasis through continued refinement of synaptic connections. Thorough understanding of the mechanisms involved in these processes may lead to novel targets for the treatment of CNS diseases involving aberrant complement-mediated synapse loss.

中文翻译：

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补体的神经保护作用与神经炎症作用：从发育到疾病

补体蛋白是先天免疫的古老成分，已成为神经网络的关键调节剂。我们在中枢神经系统发育、急性中枢神经系统病毒感染以及感染后和非感染性中枢神经系统疾病的背景下讨论这些作用，重点是小胶质细胞介导的突触丢失。尽管有大量例子表明经典补体蛋白及其受体与 CNS 功能障碍有关，但最近的数据表明它们通过持续完善突触连接在 CNS 稳态中发挥神经保护作用。深入了解这些过程所涉及的机制可能会导致治疗涉及异常补体介导的突触丢失的 CNS 疾病的新靶点。