Disease-associated astrocyte subsets contribute to the pathology of neurologic diseases, including multiple sclerosis and experimental autoimmune encephalomyelitis^{1,2,3,4,5,6,7,8} (EAE), an experimental model for multiple sclerosis. However, little is known about the stability of these astrocyte subsets and their ability to integrate past stimulation events. Here we report the identification of an epigenetically controlled memory astrocyte subset that exhibits exacerbated pro-inflammatory responses upon rechallenge. Specifically, using a combination of single-cell RNA sequencing, assay for transposase-accessible chromatin with sequencing, chromatin immunoprecipitation with sequencing, focused interrogation of cells by nucleic acid detection and sequencing, and cell-specific in vivo CRISPR–Cas9-based genetic perturbation studies we established that astrocyte memory is controlled by the metabolic enzyme ATP-citrate lyase (ACLY), which produces acetyl coenzyme A (acetyl-CoA) that is used by histone acetyltransferase p300 to control chromatin accessibility. The number of ACLY⁺p300⁺ memory astrocytes is increased in acute and chronic EAE models, and their genetic inactivation ameliorated EAE. We also detected the pro-inflammatory memory phenotype in human astrocytes in vitro; single-cell RNA sequencing and immunohistochemistry studies detected increased numbers of ACLY⁺p300⁺ astrocytes in chronic multiple sclerosis lesions. In summary, these studies define an epigenetically controlled memory astrocyte subset that promotes CNS pathology in EAE and, potentially, multiple sclerosis. These findings may guide novel therapeutic approaches for multiple sclerosis and other neurologic diseases.

与疾病相关的星形胶质细胞亚群有助于神经系统疾病的病理学，包括多发性硬化症和实验性自身免疫性脑脊髓炎^{1,2,3,4,5,6,7,8} (EAE)（多发性硬化症的实验模型）。然而，人们对这些星形胶质细胞亚群的稳定性及其整合过去刺激事件的能力知之甚少。在这里，我们报告了表观遗传控制的记忆星形胶质细胞亚群的鉴定，该亚群在再次挑战后表现出加剧的促炎症反应。具体来说，结合使用单细胞 RNA 测序、转座酶可及染色质测序分析、染色质免疫沉淀测序、通过核酸检测和测序对细胞进行集中询问，以及基于 CRISPR-Cas9 的细胞特异性体内遗传扰动研究表明，星形胶质细胞的记忆是由代谢酶 ATP-柠檬酸裂解酶 (ACLY) 控制的，该酶产生乙酰辅酶 A (乙酰辅酶 A)，组蛋白乙酰转移酶 p300 使用乙酰辅酶 A (乙酰辅酶 A) 来控制染色质的可及性。在急性和慢性 EAE 模型中，ACLY ⁺ p300 ⁺记忆星形胶质细胞的数量增加，并且它们的基因失活改善了 EAE。我们还在体外检测了人星形胶质细胞的促炎记忆表型；单细胞 RNA 测序和免疫组织化学研究检测到慢性多发性硬化症病变中ACLY ⁺ p300 ⁺星形胶质细胞数量增加。总之，这些研究定义了一种表观遗传控制的记忆星形胶质细胞亚群，可促进 EAE 以及潜在的多发性硬化症中的 CNS 病理学。这些发现可能会指导多发性硬化症和其他神经系统疾病的新治疗方法。