Cinatl Jindrich, Michaelis Martin, Fleckenstein Corinna, Bauer Gabriele, Kabicková Hanka, Scholz Martin, Rabenau Holger F, Doerr Hans Wilhelm
Institute for Medical Virology, Johann Wolfgang Goethe-University Hospital, Frankfurt, Germany.
Invest Ophthalmol Vis Sci. 2006 Feb;47(2):645-51. doi: 10.1167/iovs.05-1022.
In addition to neuroinvasive disease, West Nile virus (WNV) infection is frequently associated with self-limiting chorioretinitis and vitritis. However, the mechanisms of ophthalmic WNV infection are rarely investigated, in part because of the lack of reliable in vitro models. The authors therefore established the first model of ocular WNV infection and investigated interaction of WNV with IFN signal-transduction mechanisms.
Human retinal pigment epithelial (RPE) cells were infected with WNV strain NY385-99 at a multiplicity of infection of 5. Virus replication was evaluated by virus titers at different times after infection. The susceptibility of RPE cells to WNV infection was confirmed by transmission electron microscopy. IFN-beta expression was assessed by quantitative real-time PCR and by measurements of antiviral activity in cell culture supernatants. IFN signaling was evaluated by phosphorylation of transducer and activator of transcription 1 and 2 (STAT1/2) proteins, with immunoblot analysis.
RPE cells appeared to be highly sensitive to WNV infection. Maximum viral titers were found 24 hours after infection, followed by a continuous decline during the course of infection. WNV infection of RPE cells was followed by increased IFN-beta expression associated with IFN signaling and subsequent inhibition of WNV replication.
In this study, the first cell culture model of ophthalmic WNV infection was developed and characterized in RPE cells, and the molecular mechanisms of WNV infection were studied. The data suggest that WNV induces a general antiviral state in RPE cells. This general antiviral state correlates with WNV-induced IFN signaling in retinal cells.
除了神经侵袭性疾病外，西尼罗河病毒（WNV）感染还常与自限性脉络膜视网膜炎和葡萄膜炎相关。然而，眼部WNV感染的机制很少被研究，部分原因是缺乏可靠的体外模型。因此，作者建立了首个眼部WNV感染模型，并研究了WNV与干扰素信号转导机制的相互作用。
用感染复数为5的WNV毒株NY385 - 99感染人视网膜色素上皮（RPE）细胞。通过感染后不同时间的病毒滴度评估病毒复制情况。通过透射电子显微镜确认RPE细胞对WNV感染的易感性。通过定量实时PCR和测量细胞培养上清液中的抗病毒活性来评估干扰素-β的表达。通过免疫印迹分析，以转录激活因子1和2（STAT1/2）蛋白的磷酸化来评估干扰素信号传导。
RPE细胞似乎对WNV感染高度敏感。感染后24小时发现病毒滴度最高，随后在感染过程中持续下降。RPE细胞感染WNV后，干扰素-β表达增加，与干扰素信号传导相关，随后WNV复制受到抑制。
在本研究中，首个眼部WNV感染的细胞培养模型在RPE细胞中建立并进行了表征，同时研究了WNV感染的分子机制。数据表明，WNV在RPE细胞中诱导了一种普遍的抗病毒状态。这种普遍的抗病毒状态与WNV诱导的视网膜细胞中的干扰素信号传导相关。
