INTERFERON'S ROLE IN ANTIVIRAL ACTIVITIES

干扰素在抗病毒活性中的作用

基本信息

批准号：
2701365
负责人：
Jerry L Taylor
金额：
$ 24.23万
依托单位：
MEDICAL COLLEGE OF WISCONSIN
依托单位国家：
美国
项目类别：
财政年份：
1987
资助国家：
美国
起止时间：
1987-05-01 至 2000-04-30
项目状态：
已结题

项目摘要

Interferons (IFN) are proteins produced by cells in response to virus infection. There are three major IFN types, alpha, beta, and gamma. IFNs are not directly antiviral, but induce their antiviral actions by binding to cell receptors and inducing the production of a group of 20 or more proteins, some of which have been shown to be responsible for antiviral activity. IFNs play important roles in the response to herpes simplex virus (HSV) infections, including ocular infections causing herpetic keratitis and acute retinal necrosis. IFN-alpha combined with acyclovoir, an inhibitor of HSV DNA synthesis, produced synergistic anti-HSV activity in cornea stromal cells. In these cells IFN-alpha was found to reduce the level of several members of the early temporal class of proteins. These affected proteins are enzymes responsible for nucleoside metabolism and for viral DNA replication. Although early proteins levels are decreased, the mRNA levels which encode these enzymes were increased. Three mechanisms for this regulation will be investigated; (i) a decrease in mRNA association with polysomes, (ii) a decrease rate of translation, or (iii) an increase in the degradation of protein. The function of four IFN- inducible proteins with known antiviral action against other viruses will be studied: (i) The activity of the double-stranded RNA-activated protein kinase that phosphorylates a factor required for initiation of translation will be measured; (ii) The binding of IFN-induced RNA-binding proteins, for example 9-27, will be detected by gel shift assay; (iii) The binding of HSV early protein to the p15 protein, a protein with sequence homology to ubiquitin, the protein that binds to and targets proteins for degradation will be examined by immunoprecipitation and immunoblot; and (iv) The Mx protein that appears to function in protein transport within the cells will be assessed by immunofluorescence for co-localization with HSV proteins. The three major types of IFNs will be tested to determine whether their combined function in cornea stromal cells is synergistic with each other and with acyclovir in the inhibition of HSV replication and whether they also inhibit early protein synthesis or function by different mechanisms. Finally, we will examine the effects of IFN's on HSV replication in retinal pigment epithelial cells, a target cell for the virus infection in acute retinal necrosis. The mechanism of action of IFNs in these retinal cells will be assessed to determine whether IFNs effects are the same as in cornea stromal cells. These studies will allow us to understand how endogenously produced IFNs function to restrict HSV replication during ocular infection and how they may be used exogenously alone or with conventional antiviral agents to treat HSV ocular infections.

干扰素（IFN）是细胞对病毒产生的蛋白质感染。有三种主要的IFN类型，Alpha，Beta和Gamma。 IFNS 不是直接抗病毒，而是通过结合诱导其抗病毒作用到细胞受体并诱导一组20或更多蛋白质，其中一些已被证明是抗病毒的原因活动。 IFNS在对单纯疱疹的反应中起着重要的作用病毒（HSV）感染，包括眼感染引起疱疹感染角膜炎和急性视网膜坏死。 IFN-alpha与Acyclovoir相结合， HSV DNA合成的抑制剂，产生协同抗HSV活性在角膜基质细胞中。在这些细胞中，发现IFN-α可减少早期时间蛋白质的几个成员的水平。这些受影响的蛋白质是负责核苷代谢的酶，用于病毒DNA复制。尽管早期蛋白质水平降低，但编码这些酶的mRNA水平增加。三种机制因为该法规将被调查；（i）mRNA减少与多聚体相关，（ii）降低翻译率，或（iii）蛋白质降解的增加。四个IFN-的功能具有已知抗病毒作用针对其他病毒的诱导蛋白将研究：（i）双链RNA激活蛋白的活性激酶磷酸化引发翻译所需的因素将测量；（ii）IFN诱导的RNA结合蛋白的结合，例如，9-27将通过凝胶移位分析检测到；（iii）结合 HSV早期蛋白的p15蛋白，一种具有序列同源性的蛋白到泛素，与蛋白质结合并靶向蛋白质的蛋白质免疫沉淀和免疫印迹将检查降解；和（iv）似乎在蛋白质转运中起作用的MX蛋白细胞将通过免疫荧光评估，以共定位 HSV蛋白。将对三种主要类型的IFN进行测试以确定它们在角膜基质细胞中的合并功能是否与彼此，并在抑制HSV复制和它们是否还抑制早期蛋白质合成还是通过不同的作用机制。最后，我们将研究IFN对HSV的影响在视网膜色素上皮细胞中复制，一种目标细胞急性视网膜坏死中的病毒感染。 IFN的作用机理在这些视网膜细胞中，将评估以确定IFNS是否影响与角膜基质细胞相同。这些研究将使我们能够了解内源产生的IFN功能如何限制HSV 眼部感染期间的复制以及如何外源使用单独或与常规抗病毒药物治疗HSV眼感染。