RESUMEN
West Nile virus is a globally spread zoonotic arbovirus. The laboratory diagnosis of WNV infection relies on virus identification by RT-PCR or on specific antibody detection by serological tests, such as ELISA or virus-neutralization. These methods usually require a preparation of the whole virus as antigen, entailing biosafety issues and therefore requiring BSL-3 facilities. For this reason, recombinant antigenic structures enabling effective antibody recognition comparable to that of the native virions, would be advantageous as diagnostic reagents. WNV virions are enveloped spherical particles made up of 3 structural proteins (C, capsid; M, membrane and E, envelope) enclosing the viral RNA. This study describes the co-expression of these 3 proteins yielding non-infectious virus-like particles (VLPs) and the results of the initial assessment of these VLPs, used instead of the whole virus, that were shown to perform correctly in two different ELISAs for WNV diagnosis.
Asunto(s)
Anticuerpos Antivirales/sangre , Antígenos Virales/inmunología , Enfermedades de los Caballos/diagnóstico , Virosomas/inmunología , Fiebre del Nilo Occidental/veterinaria , Animales , Antígenos Virales/genética , Línea Celular , Expresión Génica , Caballos , Insectos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Estructurales Virales/genética , Proteínas Estructurales Virales/inmunología , Virosomas/genética , Virosomas/aislamiento & purificación , Fiebre del Nilo Occidental/diagnóstico , Virus del Nilo Occidental/genética , Virus del Nilo Occidental/inmunologíaRESUMEN
Bladder cancer is a highly prevalent human disease in which retinoblastoma (Rb) pathway inactivation and epigenetic alterations are common events. However, the connection between these two processes is still poorly understood. Here, we show that the in vivo inactivation of all Rb family genes in the mouse urothelium is sufficient to initiate bladder cancer development. The characterization of the mouse tumors revealed multiple molecular features of human bladder cancer, including the activation of E2F transcription factor and subsequent Ezh2 expression and the activation of several signaling pathways previously identified as highly relevant in urothelial tumors. These mice represent a genetically defined model for human high-grade superficial bladder cancer. Whole transcriptional characterizations of mouse and human bladder tumors revealed a significant overlap and confirmed the predominant role for Ezh2 in the downregulation of gene expression programs. Importantly, the increased tumor recurrence and progression in human patients with superficial bladder cancer is associated with increased E2F and Ezh2 expression and Ezh2-mediated gene expression repression. Collectively, our studies provide a genetically defined model for human high-grade superficial bladder cancer and demonstrate the existence of an Rb-E2F-Ezh2 axis in bladder whose disruption can promote tumor development.