Zhang Lening, Handyside Britta, Murphy Ryan, Sihn Choong-Ryoul, Xie Lin, Vitelli Catherine, Harmon Danielle, Sisó Sílvia, Liu Su, Bullens Sherry, Bunting Stuart, Fong Sylvia
Translational Biology, BioMarin Pharmaceutical, Novato, CA, USA.
Mol Ther Methods Clin Dev. 2019 Nov 21;17:13-20. doi: 10.1016/j.omtm.2019.11.007. eCollection 2020 Jun 12.
AAV5-hFVIII-SQ (valoctocogene roxaparvovec) is an adeno-associated virus (AAV)-mediated gene therapy vector containing a B-domain-deleted human factor VIII (hFVIII-SQ) transgene. In a phase 1/2 clinical study of AAV5-hFVIII-SQ for severe hemophilia A (FVIII < 1 IU/dL), participants received prednisolone to mitigate potential immune-mediated reactions to the gene therapy and demonstrated concomitant elevations in plasma FVIII levels, following a single administration of AAV5-hFVIII-SQ. To assess whether prednisolone is capable of directly modulating transgene expression or levels of circulating hepatic enzymes, C57BL/6 mice were given intravenous vehicle, 2 × 10 vector genomes (vg)/kg AAV5-hFVIII-SQ, or 6 × 10 vg/kg AAV5-hFVIII-SQ, followed by either daily oral prednisolone or water. Mice were euthanized 4 or 13 weeks after vector administration. Hepatic hFVIII-SQ DNA, RNA, and protein (immunostaining), plasma hFVIII-SQ protein and FVIII activity, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured. Liver hFVIII-SQ DNA, RNA, and plasma hFVIII-SQ protein and activity increased in a dose-dependent manner, with or without prednisolone. In summary, chronic prednisolone treatment in mice treated with AAV5-hFVIII-SQ did not modulate levels of liver hFVIII-SQ DNA, RNA, or the percentage and distribution of hFVIII-SQ-positive hepatocytes, nor did it regulate levels of plasma hFVIII-SQ protein or activity, or affect levels of plasma AST or ALT.
AAV5-hFVIII-SQ（valoctocogene roxaparvovec）是一种腺相关病毒（AAV）介导的基因治疗载体，包含一个缺失B结构域的人凝血因子VIII（hFVIII-SQ）转基因。在一项针对重度A型血友病（FVIII < 1 IU/dL）的AAV5-hFVIII-SQ 1/2期临床研究中，参与者接受泼尼松龙以减轻对基因治疗的潜在免疫介导反应，并在单次给予AAV5-hFVIII-SQ后，血浆FVIII水平随之升高。为了评估泼尼松龙是否能够直接调节转基因表达或循环肝酶水平，给C57BL/6小鼠静脉注射载体、2×10载体基因组（vg）/kg AAV5-hFVIII-SQ或6×10 vg/kg AAV5-hFVIII-SQ，随后每日口服泼尼松龙或水。在载体给药后4周或13周对小鼠实施安乐死。测量肝脏hFVIII-SQ DNA、RNA和蛋白质（免疫染色）、血浆hFVIII-SQ蛋白质和FVIII活性、天冬氨酸转氨酶（AST）和丙氨酸转氨酶（ALT）。无论有无泼尼松龙，肝脏hFVIII-SQ DNA、RNA以及血浆hFVIII-SQ蛋白质和活性均呈剂量依赖性增加。总之，用AAV5-hFVIII-SQ治疗的小鼠长期接受泼尼松龙治疗，并未调节肝脏hFVIII-SQ DNA、RNA水平或hFVIII-SQ阳性肝细胞的百分比及分布，也未调节血浆hFVIII-SQ蛋白质或活性水平，或影响血浆AST或ALT水平。
