传染病和干扰素

Infectious diseases and Interferons
　

干扰素是与各种抗病毒、抗增殖和免疫调节活性相关的非特异性调节蛋白家族。干扰素有两种主要类型。1型(α和β)所有有核细胞在感染病毒后分泌干扰素（Interferon);Interferon-α主要是由病毒感染的白细胞分泌,interferon-β 由成纤维细胞分泌。

大约有20个亚型的interferon-α有着高度的氨基酸序列同源性,但有不同的抗病毒药物和生物对人类细胞在体外的影响。II型(γ或免疫)干扰素是抗原或分裂原刺激的（mitogen-stimulated）淋巴细胞的产物。

干扰素的主要类型除了由不同的细胞产生外，还具有独特的生物学效应和物理化学性质。干扰素对广泛的病毒具有活性;一般来说，RNA病毒比DNA病毒更容易受影响。

干扰素没有直接的抗病毒活性，而是通过诱导暴露细胞中产生20多种效应蛋白来发挥抗病毒作用。抗病毒的作用是通过抑制病毒渗透或脱壳、mRNA的合成或甲基化、病毒蛋白翻译或病毒组装和释放来介导的。

对特定病毒的主要抑制作用因病毒科而异，单个病毒可被抑制不止一步。干扰素和免疫系统其他成分之间复杂的相互作用也能促进抗病毒活性，从而改变宿主对感染的反应。

Infectious diseases and Interferons

Interferons are a family of nonspecific regulatory proteins associated with a variety of antiviral, antiproliferative, and immunomodulating activities. There are two major types of interferons. Type 1 (α and β) interferons are secreted by all nucleated cells after viral infection; interferon-α is predominantly produced by virus-infected leukocytes, and interferon-β by fibroblasts. There are about 20 subtypes of interferon-α that share a high degree of amino acid sequence homology but have different antiviral and biologic effects on human cells in vitro. Type II (γ, or immune) interferon is the product of antigen- or mitogen-stimulated lymphocytes. In addition to being produced by different cells, the major types of interferon are immunologically distinct and have unique biologic effects and physicochemical properties. Interferons are active against a broad range of viruses; in general, RNA viruses are more susceptible than DNA viruses.
Interferons do not have direct antiviral activity, but rather exert antiviral effects by inducing production of more than two dozen effector proteins in exposed cells. Antiviral effects are mediated by inhibition of viral penetration or uncoating, synthesis or methylation of mRNA, viral protein translation, or viral assembly and release. The main inhibitory effect for specific viruses differs among virus families, and individual viruses can be inhibited at more than one step. Antiviral activity also can be facilitated by the complex interactions between interferons and other components of the immune system, resulting in modification of host response to infection.

Interferon - an overview | ScienceDirect Topics https://www.sciencedirect.com/topics/medicine-and-dentistry/interferon