Falsig Jeppe, van Beek Johan, Hermann Corinna, Leist Marcel
Institute of Neuropathology, Universitaetsspital Zürich, Zuerich, Switzerland.
J Neurosci Res. 2008 May 15;86(7):1434-47. doi: 10.1002/jnr.21590.
Classical immunology textbooks have described the central nervous system as an immune-privileged site, i.e., as devoid of inflammatory and host-vs.-graft immunoreactions. This view has been refined, since we now know that hematopoietic cells infiltrate the CNS under certain circumstances and that CNS-resident cells are capable of launching an innate immune response. Microglia cells express an extensive repertoire of pattern-recognition receptors and act as sentinels surveilling the CNS for possible damage or infection. Astrocytes are the most abundant cell type in the brain, and they are capable of launching a strong supportive innate immune response. Novel findings show that both astrocytes and, surprisingly, even neurons express pattern-recognition receptors. Activation of these receptors leads to a functional response, indicating that cells other than microglia are capable of initiating a primary innate immune response against CNS-invading pathogens. Here, we put these findings into context with what has been learned from recent in vitro and in vivo experiments about the initiation of an innate immune response in the brain.
经典免疫学教科书将中枢神经系统描述为一个免疫特权部位，即不存在炎症和宿主对移植物的免疫反应。这一观点已得到完善，因为我们现在知道，造血细胞在某些情况下会浸润中枢神经系统，而且中枢神经系统驻留细胞能够引发先天性免疫反应。小胶质细胞表达多种模式识别受体，并作为哨兵监测中枢神经系统是否可能受到损伤或感染。星形胶质细胞是大脑中最丰富的细胞类型，它们能够引发强烈的支持性先天性免疫反应。新的研究结果表明，星形胶质细胞，令人惊讶的是，甚至神经元也表达模式识别受体。这些受体的激活会导致功能性反应，这表明除小胶质细胞外的其他细胞也能够针对侵入中枢神经系统的病原体启动原发性先天性免疫反应。在此，我们结合最近关于大脑中先天性免疫反应启动的体外和体内实验所获得的知识，对这些研究结果进行阐述。
