Stankovics J, Crane A M, Andrews E, Wu C H, Wu G Y, Ledley F D
Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030.
Hum Gene Ther. 1994 Sep;5(9):1095-104. doi: 10.1089/hum.1994.5.9-1095.
Methylmalonic acidemia resulting from genetic deficiency of methylmalonyl CoA mutase (MCM) is an often fatal metabolic disease. Somatic gene therapy for this disorder may require gene replacement in the liver. We describe overexpression of MCM in the liver of mice after in vivo gene delivery using asialoglycoprotein/polylysine/DNA (ASO/PL/DNA) targeted delivery to the liver of plasmids expressing recombinant MCM. After intravenous administration of the ASO/PL/DNA complex, the vector sequences are cleared from the blood with t1/2 = 2.5 min and > 95% of the vector is taken up by the liver. Vector sequences are cleared from the liver with t1/2 = 1.0-1.3 hr. MCM enzyme activity in the liver increases to levels 30-40% over baseline 6-24 hr after injection. No acute or chronic toxicity was observed. This net level of expression is likely to be therapeutic for MCM if the complex could be administered repetitively to treat acute episodes of life-threatening acidosis or establish a steady-state level of MCM activity. Repetitive administration of the ASO/PL/DNA complexes in mice was associated with formation of antibodies against asialo-orosomucoid and the asialo-orosomucoid complex but not against DNA.
由于甲基丙二酰辅酶A变位酶（MCM）基因缺陷导致的甲基丙二酸血症是一种常致命的代谢疾病。针对这种疾病的体细胞基因治疗可能需要在肝脏中进行基因替换。我们描述了在使用去唾液酸糖蛋白/聚赖氨酸/DNA（ASO/PL/DNA）将表达重组MCM的质粒靶向递送至肝脏后，小鼠肝脏中MCM的过表达情况。静脉注射ASO/PL/DNA复合物后，载体序列在血液中的清除半衰期为2.5分钟，且>95%的载体被肝脏摄取。载体序列在肝脏中的清除半衰期为1.0 - 1.3小时。注射后6 - 24小时，肝脏中的MCM酶活性比基线水平提高30 - 40%。未观察到急性或慢性毒性。如果能够重复给药该复合物以治疗危及生命的酸中毒急性发作或建立稳定的MCM活性水平，这种表达净水平可能对MCM具有治疗作用。在小鼠中重复给药ASO/PL/DNA复合物与形成抗去唾液酸血清类黏蛋白和去唾液酸血清类黏蛋白复合物的抗体有关，但与抗DNA抗体无关。
