Louboutin Jean-Pierre, Wang Lili, Wilson James M
Gene Therapy Program, Department of Medicine, Division of Medical Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA.
J Gene Med. 2005 Apr;7(4):442-51. doi: 10.1002/jgm.686.
Skeletal muscle is an interesting target for gene delivery because of its mass and because the vectors can be delivered in a noninvasive way. Adeno-associated virus (AAV) vectors are capable of transducing skeletal muscle fibers and achieving stable and safe transgene expression. To date, most animal experiments using AAV have been based on AAV serotype 2, but some recent studies have demonstrated that AAV1 is more efficient than AAV2/2 in transducing muscle fibers. Recently, novel AAVs (AAV7 and AAV8) were isolated from rhesus macaques.
We injected three different muscles (gastrocnemius, soleus, biceps femoris) of immunocompetent C57BL/6 mice with different pseudotyped AAV serotypes (AAV2/1, AAV2/2, AAV2/5, AAV2/7 and AAV2/8) and quantitatively compared the different gene transfer efficiencies.
The efficiencies of transduction in skeletal muscle with AAV2/7 and AAV2/8 were similar to AAV2/1, and higher than that seen with AAV2/2 and AAV2/5. All serotypes were able to transduce both slow and fast muscle fibers similarly at the vector titer used (1x10(11) genome copies per mouse). Despite a limited inflammatory response (slightly higher when using AAV2/2, AAV2/7 and AAV2/8 vectors than AAV2/1 and AAV2/5), transgene expression was observed throughout the length of the experiment.
These results show that AAV2/7 and AAV2/8 are able to transduce muscle fibers of immunocompetent mice very efficiently, offering new perspectives in gene transfer of skeletal muscle.
骨骼肌因其质量以及载体能够以非侵入性方式递送，成为基因递送的一个有趣靶点。腺相关病毒（AAV）载体能够转导骨骼肌纤维并实现稳定且安全的转基因表达。迄今为止，大多数使用AAV的动物实验都基于AAV2血清型，但最近的一些研究表明，AAV1在转导肌纤维方面比AAV2/2更有效。最近，新型AAV（AAV7和AAV8）从恒河猴中分离出来。
我们向免疫功能正常的C57BL/6小鼠的三种不同肌肉（腓肠肌、比目鱼肌、股二头肌）注射不同假型的AAV血清型（AAV2/1、AAV2/2、AAV2/5、AAV2/7和AAV2/8），并定量比较不同的基因转移效率。
AAV2/7和AAV2/8在骨骼肌中的转导效率与AAV2/1相似，且高于AAV2/2和AAV2/5。在所用载体滴度（每只小鼠1×10¹¹个基因组拷贝）下，所有血清型都能同样高效地转导慢肌纤维和快肌纤维。尽管炎症反应有限（使用AAV2/2、AAV2/7和AAV2/8载体时比AAV2/1和AAV2/5略高），但在整个实验过程中都观察到了转基因表达。
这些结果表明，AAV2/7和AAV2/8能够非常高效地转导免疫功能正常小鼠的肌纤维，为骨骼肌基因转移提供了新的视角。
