O'Connor Deirdre M, Lutomski Corinne, Jarrold Martin F, Boulis Nicholas M, Donsante Anthony
Department of Neurosurgery, Emory University School of Medicine, Atlanta, Georgia.
Chemistry, Indiana University Bloomington, Bloomington, Indiana.
Hum Gene Ther Methods. 2019 Dec;30(6):214-225. doi: 10.1089/hgtb.2019.105.
Viral vectors are complex drugs that pose a particular challenge for manufacturing. Previous studies have shown that, unlike small-molecule drugs, vector preparations do not yield a collection of identical particles. Instead, a mixture of particles that vary in capsid stoichiometry and impurities is created, which may differ from lot to lot. The consequences of this are unclear, but conflicting reports regarding the biological properties of vectors, including transduction patterns, suggest that this variability may have an effect. However, other variables, including differences in animal strains and techniques, make it difficult to identify a cause. Here, we report lot-to-lot variation in spinal cord gray matter transduction following intrathecal delivery of self-complementary adeno-associated virus serotype 9 vectors. Eleven lots of vector were evaluated from six vector cores, including one preclinical/Good Laboratory Practice lot. Eight of the lots, including the preclinical lot, failed to transduce the gray matter, whereas the other three provided robust transduction. The cause for this variation is unknown, but it did not correlate with vector titer, buffer, or purification method. These results highlight the need to identify the cause of this variation and to develop improved production and quality control methods to ensure lot-to-lot consistency of vector potency.
病毒载体是一类复杂的药物，其生产面临着特殊的挑战。以往的研究表明，与小分子药物不同，载体制剂不会产生一批相同的颗粒。相反，会产生衣壳化学计量和杂质不同的颗粒混合物，不同批次之间可能存在差异。其后果尚不清楚，但关于载体生物学特性（包括转导模式）的相互矛盾的报告表明，这种变异性可能会产生影响。然而，包括动物品系和技术差异在内的其他变量，使得难以确定原因。在此，我们报告了鞘内注射自互补腺相关病毒9型载体后脊髓灰质转导的批次间差异。对来自六个载体核心的11批载体进行了评估，包括一批临床前/良好实验室规范批次。其中八批，包括临床前批次，未能转导灰质，而其他三批则提供了强大的转导。这种变异的原因尚不清楚，但它与载体滴度、缓冲液或纯化方法无关。这些结果凸显了确定这种变异原因以及开发改进的生产和质量控制方法以确保载体效力批次间一致性的必要性。
