Tinkey Rachel A, Smith Brandon C, Habean Maria L, Williams Jessica L
bioRxiv. 2024 Jul 16:2024.07.10.602938. doi: 10.1101/2024.07.10.602938.
Astrocytic interferon (IFN)γ signaling is associated with a reduction in neuroinflammation. We have previously shown that the benefits of astrocytic IFNγ arise from a variety of mechanisms; however, downstream effectors responsible for regulating this protection are unknown. We address this by identifying a specific transcription factor that may play a key role in modulating the consequences of IFNγ signaling. RNA-sequencing of primary human astrocytes treated with IFNγ revealed basic leucine zipper ATF-like transcription factor ( )2 as a highly expressed interferon-specific gene. Primarily studied in the periphery, BATF2 has been shown to exert both inflammatory and protective functions; however, its function in the central nervous system (CNS) is unknown. Here, we demonstrate that human spinal cord astrocytes upregulate BATF2 transcript and protein in an IFNγ-specific manner. Additionally, we found that BATF2 prevents overexpression of interferon regulatory factor (IRF)1 and IRF1 targets such as Caspase-1, which are known downstream pro-inflammatory mediators. We also show that mice exhibit exacerbated clinical disease severity in a murine model of CNS autoimmunity, characterized by an increase in both CNS immune cell infiltration and demyelination. mice also exhibit increased astrocyte-specific expression of IRF1 and Caspase-1, suggesting an amplified interferon response . Further, we demonstrate that BATF2 is expressed primarily in astrocytes in MS lesions and that this expression is co-localized with IRF1. Collectively, our results further support a protective role for IFNγ and implicate BATF2 as a key suppressor of overactive immune signaling in astrocytes during neuroinflammation.
星形胶质细胞的干扰素(IFN)γ信号传导与神经炎症的减轻有关。我们之前已经表明,星形胶质细胞IFNγ的益处源于多种机制;然而,负责调节这种保护作用的下游效应器尚不清楚。我们通过鉴定一种可能在调节IFNγ信号传导后果中起关键作用的特定转录因子来解决这个问题。用IFNγ处理的原代人星形胶质细胞的RNA测序显示,碱性亮氨酸拉链ATF样转录因子( )2是一个高表达的干扰素特异性基因。BATF2主要在外周进行研究,已被证明具有炎症和保护功能;然而,其在中枢神经系统(CNS)中的功能尚不清楚。在这里,我们证明人脊髓星形胶质细胞以IFNγ特异性方式上调BATF2转录本和蛋白质。此外,我们发现BATF2可防止干扰素调节因子(IRF)1及其靶标如Caspase-1的过表达,Caspase-1是已知的下游促炎介质。我们还表明, 小鼠在中枢神经系统自身免疫性疾病的小鼠模型中表现出临床疾病严重程度加剧,其特征是中枢神经系统免疫细胞浸润和脱髓鞘均增加。 小鼠还表现出IRF1和Caspase-1的星形胶质细胞特异性表达增加,表明干扰素反应增强 。此外,我们证明BATF2主要在多发性硬化症病变的星形胶质细胞中表达,并且这种表达与IRF1共定位。总的来说,我们的结果进一步支持了IFNγ的保护作用,并表明BATF2是神经炎症期间星形胶质细胞中过度活跃的免疫信号的关键抑制因子。