XLMTM dog transcriptome remodeling by gene therapy

Gene therapy using recombinant adeno-associated virus (rAAV) vectors is an attractive approach to treat neuromuscular disorders resulting from single gene mutations. Despite encouraging results in large animal models and in recent clinical trials, gene therapy is sometimes considered a “hit-or-miss” technology, because the exact molecular mechanisms driving disease rescue remain elusive, and biomarkers of rAAV corrective impact in target cells are missing. In this study, the complete rescue of X-linked myotubular myopathy (XLMTM) after gene therapy in dogs was used as a model to develop analytical tools and help decipher the impact of the treatment on the muscle transcriptome. RNA-sequencing was performed on samples from two different muscles (Biceps femoris and Vastus lateralis) in a pre-existing colony of 13 dogs that were included in a dose-finding study published in 2017 (Mack D.L. et al.,Molecular Therapy 2017 Apr 5;25(4):839-854).

采用重组腺相关病毒（recombinant adeno-associated virus, rAAV）载体的基因治疗，是治疗单基因突变所致神经肌肉疾病的极具潜力的治疗策略。尽管在大型动物模型与近期临床试验中已取得令人鼓舞的成果，但基因治疗有时仍被视为一项成败难料的技术，这是因为介导疾病病情改善的确切分子机制仍不明晰，且靶细胞中rAAV治疗效应的生物标志物仍缺失。本研究以犬类经基因治疗后X连锁肌管肌病（X-linked myotubular myopathy, XLMTM）获得完全缓解作为研究模型，用于开发分析工具并解析该治疗对肌肉转录组的影响。研究对13只预先繁育的实验犬的两种肌肉样本——股二头肌（Biceps femoris）与股外侧肌（Vastus lateralis）——开展了RNA测序（RNA-sequencing），这些实验犬均纳入2017年发表的一项剂量探索研究（Mack D.L.等，《分子治疗》2017年4月5日；25(4):839-854）。