Astrocytes are neural parenchymal cells that ubiquitously tile the central nervous system (CNS). In addition to playing essential roles in healthy tissue, astrocytes exhibit an evolutionarily ancient response to all CNS insults, referred to as astrocyte reactivity. Long regarded as passive and homogeneous, astrocyte reactivity is being revealed as a heterogeneous and functionally powerful component of mammalian CNS innate immunity. Nevertheless, concepts about what astrocyte reactivity comprises and what it does are incomplete and sometimes controversial. This review discusses the goal of differentiating reactive astrocyte subtypes and states based on composite pictures of molecular expression, cell morphology, cellular interactions, proliferative state, normal functions, and disease-induced dysfunctions. A working model and conceptual framework is presented for characterizing the diversity of astrocyte reactivity.

星形胶质细胞是普遍存在于中枢神经系统 (CNS) 中的神经实质细胞。除了在健康组织中发挥重要作用外，星形胶质细胞对所有中枢神经系统损伤表现出进化上古老的反应，称为星形胶质细胞反应性。长期以来被认为是被动和同质的，星形胶质细胞反应性被揭示为哺乳动物中枢神经系统先天免疫的异质和功能强大的组成部分。然而，关于星形胶质细胞反应性包括什么及其作用的概念是不完整的，有时是有争议的。本综述讨论了基于分子表达、细胞形态、细胞相互作用、增殖状态、正常功能和疾病引起的功能障碍的复合图片来区分反应性星形胶质细胞亚型和状态的目标。