Huang Qi, Wang Kai, Pan Ling, Qi Kezong, Liu Hongmei, Chen Hongjun
College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Shanghai Veterinary Research Institute, Chinese Academic of Agricultural Sciences, Shanghai, 200241 PR China.
College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China.
Vet Microbiol. 2017 May;203:110-116. doi: 10.1016/j.vetmic.2017.02.015. Epub 2017 Mar 6.
Chicken surfactant protein A (cSP-A) is a collectin believed to play an important role in antiviral immunity. However, cSP-A expression in the respiratory tract of chickens after viral co-infection remains unclear. The aim of this study was the detection and characterization of cSP-A in co-infected chickens. For this purpose, four-week-old specific pathogen-free (SPF) chickens were divided into five groups and inoculated intranasally with H9N2 subtype avian influenza virus (AIV), infectious bronchitis virus (IBV), or Newcastle disease virus (NDV). Chickens were sacrificed at three days post inoculation, and the lung, trachea, and air sac samples were taken to determine histological changes and expression levels of cSP-A mRNA and cSP-A protein. The cSP-A mRNA and its protein were detected separately using real-time quantitative reverse transcriptional polymerase chain reaction (qRT-PCR), a sandwich enzyme-linked immunosorbent assay (S-ELISA), and an immunohistochemistry assay (IHC). In comparison, for the PBS group as the negative group and the NDV-infected group as the positive group, the histological changes showed that the lesions of the AIV+ IBV co-infected group were more serious compared to the AIV-infected group and the IBV-infected group. Consequently, the expression level of cSP-A in the AIV+IBV co-infected group significantly decreased when compared to the AIV-infected group and the IBV-infected group by qRT-PCR, ELISA, and IHC analysis. The mechanism of the downregulation of SP-A expression level will be addressed in future.
鸡表面活性蛋白A（cSP-A）是一种凝集素，被认为在抗病毒免疫中发挥重要作用。然而，病毒共感染后鸡呼吸道中cSP-A的表达仍不清楚。本研究的目的是检测和鉴定共感染鸡中的cSP-A。为此，将4周龄的无特定病原体（SPF）鸡分为五组，通过鼻内接种H9N2亚型禽流感病毒（AIV）、传染性支气管炎病毒（IBV）或新城疫病毒（NDV）。接种后三天处死鸡，采集肺、气管和气囊样本，以确定组织学变化以及cSP-A mRNA和cSP-A蛋白的表达水平。分别使用实时定量逆转录聚合酶链反应（qRT-PCR）、夹心酶联免疫吸附测定（S-ELISA）和免疫组织化学测定（IHC）检测cSP-A mRNA及其蛋白。相比之下，以PBS组作为阴性组，以NDV感染组作为阳性组，组织学变化显示，与AIV感染组和IBV感染组相比，AIV+IBV共感染组的病变更严重。因此，通过qRT-PCR、ELISA和IHC分析，与AIV感染组和IBV感染组相比，AIV+IBV共感染组中cSP-A的表达水平显著降低。SP-A表达水平下调的机制将在未来进行探讨。
