Recent advances in recombinant adeno-associated virus (rAAV) gene therapy for choroideremia show gene replacement to be a promising approach. It is, however, well known that contact of vector solution with plastic materials in the surgical device may result in non-specific adsorption with resulting loss of physical titer and/or level of protein expression and activity. Here we assessed the biocompatibility and stability of rAAV2-REP1 (Rab Escort Protein-1) before and following passage through the injection device over a period of time to mimic the clinical scenario. Three identical devices were screened using two concentrations of vector: high (1E+12 DNase-resistant particles [DRP]/mL) and low (1E+11 DRP/mL), to mimic high- and low-dose administrations of vector product. The low dose was prepared using either formulation buffer that contained 0.001% of a non-ionic surfactant (PF68) or balanced salt solution (BSS). We observed significant losses in the genomic titer of samples diluted with BSS for all time points. The addition of 0.001% PF68 did not, however, affect rAAV physical titer, or REP1 protein expression and biological activity. Hence we observed that neither the genomic titer nor the biological activity of a rAAV2-REP1-containing solution was affected following passage through the surgical device when PF68 was present as a surfactant and this was maintained over a period up to 10 h.

中文翻译：

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当通过用于视网膜基因治疗的外科手术设备时，包含PF68表面活性剂可改善rAAV滴度的稳定性。

重组腺相关病毒（rAAV）基因疗法用于脉络膜炎的最新进展表明，基因置换是一种有前途的方法。然而，众所周知，载体溶液与手术装置中的塑料材料的接触可能导致非特异性吸附，从而导致物理滴度和/或蛋白质表达和活性水平的损失。在这里，我们评估了rAAV2-REP1（Rab Escort Protein-1）在通过注射装置经过一段时间以模拟临床情况之前和之后的生物相容性和稳定性。使用两种浓度的载体筛选了三个相同的设备：高浓度（1E + 12耐DNase的颗粒[DRP] / mL）和低浓度（1E + 11 DRP / mL），以模拟高剂量和低剂量载体产品的给药。使用包含0的任一配方缓冲液制备低剂量。001％的非离子表面活性剂（PF68）或平衡盐溶液（BSS）。我们观察到在所有时间点，用BSS稀释的样品的基因组滴度都有明显的损失。但是，添加0.001％PF68不会影响rAAV的物理滴度或REP1蛋白的表达和生物学活性。因此，我们观察到当PF68作为表面活性剂存在时，通过外科手术器械后，含rAAV2-REP1的溶液的基因组滴度和生物学活性均不会受到影响，并且可以维持长达10小时的时间。