靶向心肌组织的新型腺相关病毒载体的构建及筛选

Construction and Screening of A Novel Adeno-Associated Virus Vector Targeting Myocardial Tissue

为了构建以心肌为靶点的基因治疗载体,通过DNA shuffling技术对选择的8种AAV(AAV1~AAV4,AAV6~AAV9)衣壳基因进行了重组,构建了随机突变体AAV衣壳文库。将随机突变体AAV衣壳文库在小鼠体内直接筛选,最终筛选得到高心肌靶向和低肝脏靶向的新型AAV衣壳:AAVH50与AAVH59。通过尾静脉注射,将AAV携带的荧光素酶(Luc)基因递送到小鼠体内,结果表明:在检测的11个组织中,AAVH50与AAVH59在心肌组织的基因表达高于其他组织。与AAV6、AAV9相比,AAVH50与AAVH59心肌中的Luc表达水平相近,肝脏中的表达明显低于AAV9。AAVH50和AAVH59感染原代新生大鼠心肌细胞后,AAVH59在心肌直接感染的效率明显高于AAV9。

Cardiomyopathy is a common disease and is regarded as an important cause of premature death.The development of a gene therapy vector for cardiomyopathy is the key to gene therapy of cardiomyopathy.In order to build a gene therapy vector targeting myocardium,the eight selected AAV(AAV1−AAV4,AAV6−AAV9)capsid genes were recombined by DNA shuffling technology,and a random mutant AAV capsid library was constructed in mice direct screening.Finally the new AAV capsids with high myocardial targeting and low liver targeting,AAVH50 and AAVH59,were screened.Through the tail vein injection,the luciferase(Luc)gene carried was delivered to mice.It was found that among the eleven tissues tested,the gene expressions of AAVH50 and AAVH59 in myocardial tissue were higher than other tissues.Compared with AAV6 and AAV9,AAVH50 and AAVH59 expressed similar levels of luciferase in the myocardium,and the expression in the liver significantly decreased AAV9.After AAVH50 and AAVH59 infected primary neonatal rat cardiomyocytes,the efficiency of the selected AAVH59 in direct myocardial infection was significantly higher than that of AAV9.Therefore,this study screened to obtain a new type of AAV vector with high targeting to myocardium,and to the liver and low targeting,which is expected to provide a new type of AAV vector for gene therapy of myocardial diseases.