London/Swedish双突变APP转基因小鼠的鉴定

鉴定及评价APP双突变阿尔茨海默病的转基因小鼠模型。方法将London/Swedish双突变APP基因插入到PDGF启动子下游,构建转基因表达载体,通过显微注射法建立APP695^V652I/K596N/M597L双突变转基因C57BL/6J小鼠。PCR鉴定APP695双突变转基因小鼠的基因表型,RT-PCR和Western blotting检测APP突变基因表达,免疫组化检测APP695双突变转基因小鼠大脑病理改变。水迷宫检测APP695^V652I/K596N/M597L转基因小鼠的行为学改变。结果建立了2个品系的人APP695^V652I/K596N/M597L转基因小鼠。抗Aβ1-17免疫组织化学显示APP695双突变转基因小鼠海马区阳性细胞数较APP695^V652I单突变转基因小鼠,及野生小鼠阳性细胞数明显增多,胞膜着色明显加深。双突变转基因小鼠在5月龄时可检测到老年斑。行为学检测显示APP695^V652I/K596N/M597L双突变转基因小鼠学习记忆能力比APP695^V652I单突变转基因小鼠有明显下降。结论APP695^V652I/K596N/M597L转基因小鼠较APP695^V652I转基因小鼠更早出现老年斑及学习认知能力障碍。成功建立了人APP695^V652I/K596N/M597L转基因小鼠阿尔茨海默病模型,为研究阿尔茨海默病发病机制和药物研发提供了有价值的动物模型。

Estabfishment and Analysis of a APP695^V652I/K596N/M597L Transgenic Mouse

Objective To estabhsh a APP695^V652I/K596N/M597L double mutated gene transgenic mouse model of Alzheimer disease. Methods The transgenic plasmid was constructed by inserting the APP695^V652I/K596N/M597L gene into the downstream of PDGF promoter. The transgenic mice were produced by microinjection method and the genotyping was detected by PCR. The expression levels of the gene was determined with the RT-PCR and Western blotting. The pathologic changes were observed by microscopy. The behavioural tests were examined by the water maze trials. Results Two lines of transgenic C57BL/6J mouse of APP695^V652I/K596N/M597L gene were established. The expression of the APP695^V652I/K596N/M597L gene was detected in the brain tissues The APP695^V652I/K596N/M597L transgenic mouse showed the earlier pathological changes and spatial memory deficits compared with that of the APP695^V652I transgenic mouse and wild type mouse. Conclusions The expression of double mutant APP gene in brain caused the senile plaque and spatial memory deficits suggested that the APP gene transgenic mouse is a useful animal model of AD.