Heinig Lars, Mueller Daniel A, Ramljak Sanja, Holznagel Edgar, Stuke Andreas W
German Primate Center (DPZ), Department of Infection Biology, Kellnerweg 4, 37077 Göttingen, Germany.
Protein Expr Purif. 2010 Apr;70(2):129-36. doi: 10.1016/j.pep.2009.09.015. Epub 2009 Sep 29.
In transmissible spongiform encephalopathy (TSE) pathogenesis the cellular prion protein (PrP(C)) is converted into its pathogenic PrP(Sc) isoform. Prion protein gene (Prnp) deficient mice (PrP(0/0)) are resistant to PrP(Sc) infection, but following reconstitution of Prnp they regain their susceptibility to infection. Therefore, it is challenging to simulate this natural situation in a cell culture model. We have previously reported the inducible stable expression of a human PrP(C) in murine 3T3 cells. In this study, we used murine PrP(0/0) cells stably expressing exemplarily the chimpanzee Prnp under the control of inducible tetracycline (Tet) system. The Prnp was integrated using a lentiviral vector. Its expression in the engineered PrP(0/0)Chimp1/Tet-Off cell line was analyzed by Western blot (Wb) and fluorescence activated cell sorting (FACS) analyses. PrP(C) was partially purified by using immobilized metal affinity chromatography (IMAC). Compared to all the other cell systems which possess an endogenous PrP(C) expression, here described cell line contains only an overexpressing species specific PrP(C) expression which is tightly regulated and can be turned-off at any time without showing any endogenous host PrP(C) expression. Consequently, a contamination of the isolated PrP(C) is impossible. This cell line potentially offers a new tool for simulation of mice bioassays widely used in TSE infection studies.
在传染性海绵状脑病(TSE)发病机制中,细胞朊蛋白(PrP(C))会转化为其致病性PrP(Sc)异构体。朊蛋白基因(Prnp)缺陷小鼠(PrP(0/0))对PrP(Sc)感染具有抗性,但在Prnp重组后,它们会重新获得感染易感性。因此,在细胞培养模型中模拟这种自然情况具有挑战性。我们之前报道了人PrP(C)在鼠3T3细胞中的可诱导稳定表达。在本研究中,我们使用在可诱导四环素(Tet)系统控制下稳定表达黑猩猩Prnp的鼠PrP(0/0)细胞。Prnp使用慢病毒载体进行整合。通过蛋白质免疫印迹(Wb)和荧光激活细胞分选(FACS)分析来检测其在工程化PrP(0/0)Chimp1/Tet-Off细胞系中的表达。使用固定化金属亲和色谱(IMAC)对PrP(C)进行部分纯化。与所有其他具有内源性PrP(C)表达的细胞系统相比,这里描述的细胞系仅包含一种过表达的物种特异性PrP(C)表达,该表达受到严格调控,并且可以在任何时候关闭,而不会显示任何内源性宿主PrP(C)表达。因此,不可能污染分离出的PrP(C)。该细胞系可能为模拟TSE感染研究中广泛使用的小鼠生物测定提供一种新工具。