BACKGROUND Infectious bursal disease (IBD) is a highly contagious infectious disease that causes severe immunosuppression and damage to the bursa of Fabricius in chickens. Several proteins involved in IBD virus (IBDV) infection, such as surface immunoglobulin M, integrin, annexin A2 and chicken heat shock protein 90, have been identified. However, the main protein that plays key roles in virus infection has not yet been confirmed. METHODS DF-1 cell line was transfected with the pcDNA-VP2 plasmid and analyzed by immunofluorescence assay. The proteins reacted with VP2 of IBDV in DF-1 cells were pulldown with the monoclonal antibody and identified by mass spectrometry. Heat shock cognate protein 70 (HSC70), one of these proteins, was selected to be investigated in the function in IBDV infection by specific antibody and its inhibitor. RESULTS The DF-1 cell line was transfected with the pcDNA-VP2 plasmid, and expression of IBDV VP2 in DF-1 cells was confirmed by immunofluorescence assays. Heat shock cognate protein 70 (HSC70) was one of the proteins identified by coimmunoprecipitation using a monoclonal antibody (2H11) against VP2 and mass spectrometry analysis. IBDV infection in DF-1 cells was strongly inhibited by both an anti-HSC70 antibody and a HSC70 inhibitor (VER155008). CONCLUSION These results suggest that HSC70 may be an essential factor for IBDV infection.

中文翻译：

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HSC70是DF-1细胞中传染性法氏囊病病毒（IBDV）感染所必需的。

背景技术传染性法氏囊病（IBD）是高度传染性的传染病，其引起严重的免疫抑制和对鸡法布里克氏囊的损害。已经鉴定出几种与IBD病毒（IBDV）感染有关的蛋白质，例如表面免疫球蛋白M，整联蛋白，膜联蛋白A2和鸡热休克蛋白90。但是，尚未确认在病毒感染中起关键作用的主要蛋白质。方法用pcDNA-VP2质粒转染DF-1细胞株，并进行免疫荧光分析。用单克隆抗体将与DF-1细胞中IBDV VP2反应的蛋白下拉，并通过质谱鉴定。选择这些蛋白之一的热休克同源蛋白70（HSC70），以研究特异性抗体及其抑制剂在IBDV感染中的功能。结果用pcDNA-VP2质粒转染了DF-1细胞系，并通过免疫荧光实验证实了IBDV VP2在DF-1细胞中的表达。热休克同源蛋白70（HSC70）是使用针对VP2的单克隆抗体（2H11）和质谱分析通过共免疫沉淀法鉴定的蛋白之一。抗HSC70抗体和HSC70抑制剂（VER155008）均强烈抑制DF-1细胞中的IBDV感染。结论这些结果表明HSC70可能是IBDV感染的必要因素。热休克同源蛋白70（HSC70）是使用针对VP2的单克隆抗体（2H11）和质谱分析通过共免疫沉淀法鉴定的蛋白之一。抗HSC70抗体和HSC70抑制剂（VER155008）均强烈抑制DF-1细胞中的IBDV感染。结论这些结果表明HSC70可能是IBDV感染的必要因素。热休克同源蛋白70（HSC70）是使用针对VP2的单克隆抗体（2H11）和质谱分析通过共免疫沉淀法鉴定的蛋白之一。抗HSC70抗体和HSC70抑制剂（VER155008）均强烈抑制DF-1细胞中的IBDV感染。结论这些结果表明HSC70可能是IBDV感染的必要因素。