Yao S N, Kurachi K
Department of Human Genetics, University of Michigan Medical School, Ann Arbor 48109-0618.
Proc Natl Acad Sci U S A. 1992 Apr 15;89(8):3357-61. doi: 10.1073/pnas.89.8.3357.
Hemophilia B is an X chromosome-linked recessive bleeding disorder. To develop a somatic gene therapy for this disease, we have examined whether mouse skeletal myoblasts can serve as efficient vehicles for systemic delivery of recombinant factor IX. When mouse myoblasts (C2C12) transduced with a Moloney murine leukemia virus-based vector containing the bacterial beta-galactosidase gene were injected into mouse skeletal muscles, they fused with the existing and regenerating myofibers and continued to express beta-galactosidase. C2C12 myoblasts that were infected with recombinant retroviruses containing a human factor IX cDNA secreted biologically active human factor IX cDNA secreted biologically active human factor IX into the culture medium at a rate of 2.6 micrograms per 10(6) cells per day. Myotubes derived from these cells in culture continued to express human factor IX (0.68 micrograms/day from myotubes derived from 10(6) C2C12 cells). After injection of the transduced C2C12 myoblasts into skeletal muscles of mice, the systemic level of recombinant human factor IX was found to be as high as approximately 1 microgram/ml of serum. These results provide the rationale for using skeletal myoblasts as an efficient gene delivery vehicle in the somatic gene therapy for hemophilia B.
血友病B是一种X染色体连锁的隐性出血性疾病。为开发针对该疾病的体细胞基因疗法，我们研究了小鼠骨骼肌成肌细胞是否可作为重组因子IX全身递送的有效载体。当将用含细菌β-半乳糖苷酶基因的莫洛尼鼠白血病病毒载体转导的小鼠成肌细胞（C2C12）注射到小鼠骨骼肌中时，它们与现有的和再生的肌纤维融合并持续表达β-半乳糖苷酶。感染含人因子IX cDNA重组逆转录病毒的C2C12成肌细胞以每天每10⁶个细胞2.6微克的速率向培养基中分泌具有生物活性的人因子IX。培养中源自这些细胞的肌管持续表达人因子IX（源自10⁶个C2C12细胞的肌管每天表达0.68微克）。将转导的C2C12成肌细胞注射到小鼠骨骼肌中后，发现重组人因子IX的全身水平高达约1微克/毫升血清。这些结果为在血友病B的体细胞基因疗法中使用骨骼肌成肌细胞作为有效基因递送载体提供了理论依据。
