Interferons (IFNs) are implicated as an important component of the innate immune system influencing viral infections, inflammation, and immune surveillance. We review here the complex biological activity of IFNs in the central nervous system (CNS) and associated glial–immune interactions, with focus specifically on the Type I IFNs in physiological and pathological conditions. IFN-α and IFN-β are the predominant Type I IFNs in the CNS. They are produced in the CNS by glial cells, mostly microglia and astrocytes, as well as by neurons. A variety of mechanisms stimulate IFN production in glial cells, including innate stimuli from Toll-like and other receptors, which can recognize endogenous entities, as well as pathogens. We will review evidence that differential signaling by IFN-α versus IFN-β through the common heterodimeric receptor IFNAR is the basis for CNS-selective Type I IFN response, and the capacity of CNS glial cells to produce and respond to Type I IFN. Differential signaling outcomes of IFN-α and IFN-β, which have been ascribed to differential affinity for IFNAR1 and IFNAR2, determine whether Type I IFN exert pathogenic or protective roles in the CNS. These points will be discussed with reference to selected neurological diseases, and effects of Type I IFN on the integrity of the blood–brain barrier.

中文翻译：

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中枢神经系统中的干扰素：少数乐器会演奏许多乐曲。

干扰素（IFN）被认为是影响病毒感染，炎症和免疫监视的先天免疫系统的重要组成部分。我们在这里回顾了中枢神经系统（CNS）中IFN的复杂生物活性以及相关的神经胶质-免疫相互作用，重点是生理和病理条件下的I型IFN。IFN-α和IFN-β是中枢神经系统中主要的I型干扰素。它们是由神经胶质细胞（主要是小胶质细胞和星形胶质细胞）以及神经元在中枢神经系统中产生的。多种机制刺激神经胶质细胞中的IFN产生，包括来自Toll样受体和其他受体的先天刺激物，它们可以识别内源性实体以及病原体。我们将审查证据，证明通过共同的异二聚体受体IFNAR的IFN-α与IFN-β的差异信号传导是CNS选择性I型IFN反应的基础，也是CNS胶质细胞产生和响应I型IFN的能力。归因于对IFNAR1和IFNAR2的不同亲和力的IFN-α和IFN-β的差异信号转导结果决定了I型IFN在中枢神经系统中是否发挥致病作用或保护作用。将针对选定的神经系统疾病以及I型干扰素对血脑屏障完整性的影响进行讨论。确定I型干扰素是否在中枢神经系统中发挥致病作用或保护作用。将针对选定的神经系统疾病以及I型干扰素对血脑屏障完整性的影响进行讨论。确定I型干扰素是否在中枢神经系统中发挥致病作用或保护作用。将针对选定的神经系统疾病以及I型干扰素对血脑屏障完整性的影响进行讨论。