Haq Kamran, Wootton Sarah K, Barjesteh Neda, Golovan Serguei, Bendall Andrew, Sharif Shayan
Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1 (Haq, Wootton, Barjesteh, Sharif); Department of Animal and Food Sciences, University of Delaware, Newark, Delaware, 19716 USA (Golovan); Department of Molecular & Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, Ontario N1G 2W1 (Bendall).
Can J Vet Res. 2015 Jan;79(1):1-7.
Interferon (IFN)-γ has been shown to be associated with immunity to Marek's disease virus (MDV). The overall objective of this study was to investigate the causal relationship between IFN-γ and vaccine-conferred immunity against MDV in chickens. To this end, 3 small interfering RNAs (siRNAs) targeting chicken IFN-γ, which had previously been shown to reduce IFN-γ expression in vitro, and a control siRNA were selected to generate recombinant avian adeno-associated virus (rAAAV) expressing short-hairpin small interfering RNAs (shRNAs). An MDV challenge trial was then conducted: chickens were vaccinated with herpesvirus of turkey (HVT), administered the rAAAV expressing shRNA, and then challenged with MDV. Tumors were observed in 4 out of 10 birds that were vaccinated with HVT and challenged but did not receive any rAAAV, 5 out of 9 birds that were administered the rAAAV containing IFN-γ shRNA, and 2 out of 10 birds that were administered a control enhanced green fluorescent protein siRNA. There was no significant difference in MDV genome load in the feather follicle epithelium of the birds that were cotreated with the vaccine and the rAAAV compared with the vaccinated MDV-infected birds. These results suggest that AAAV-based vectors can be used for the delivery of shRNA into chicken cells. However, administration of the rAAAV expressing shRNA targeting chicken IFN-γ did not seem to fully abrogate vaccine-induced protection.
干扰素（IFN）-γ已被证明与马立克氏病病毒（MDV）的免疫相关。本研究的总体目标是调查IFN-γ与鸡疫苗介导的抗MDV免疫之间的因果关系。为此，选择了3种靶向鸡IFN-γ的小干扰RNA（siRNA）（先前已证明其在体外可降低IFN-γ表达）和一种对照siRNA，以产生表达短发夹小干扰RNA（shRNA）的重组禽腺相关病毒（rAAAV）。然后进行了MDV攻毒试验：用火鸡疱疹病毒（HVT）对鸡进行疫苗接种，给予表达shRNA的rAAAV，然后用MDV进行攻毒。在接种HVT并接受攻毒但未接受任何rAAAV的10只鸡中有4只观察到肿瘤，在给予含IFN-γ shRNA的rAAAV的9只鸡中有5只观察到肿瘤，在给予对照增强型绿色荧光蛋白siRNA的10只鸡中有2只观察到肿瘤。与接种疫苗并感染MDV的鸡相比，同时接受疫苗和rAAAV处理的鸡的毛囊上皮中MDV基因组载量没有显著差异。这些结果表明，基于AAAV的载体可用于将shRNA递送至鸡细胞。然而，给予表达靶向鸡IFN-γ的shRNA的rAAAV似乎并未完全消除疫苗诱导的保护作用。
