Chilukuri Nageswararao, Duysen Ellen G, Parikh Kalpana, Sun Wei, Doctor Bhupendra P, Lockridge Oksana, Saxena Ashima
Division of Biochemistry, Walter Reed Army Institute of Research, Silver Spring, MD 20910-7500, USA.
Chem Biol Interact. 2008 Sep 25;175(1-3):327-31. doi: 10.1016/j.cbi.2008.04.009. Epub 2008 May 21.
Human serum butyrylcholinesterase (Hu BChE) is a promising therapeutic against the toxicity of chemical warfare nerve agents, pesticide intoxication, and cocaine overdose. However, its widespread application is hampered by difficulties in large-scale production of the native protein from human plasma and/or availability as a recombinant protein suitable for use in vivo. This limitation may be resolved by in vivo delivery and expression of the Hu BChE gene. In this study, recombinant (r) adenoviruses (Ads) encoding full-length and truncated rHu BChEs were tested for in vivo expression in mice. Mice injected with these rAds intraperitoneally failed to express rHu BChE. However, a single tail vein injection of both rAds resulted in persistent high serum levels of rHu BChE in BChE knockout mice, which peaked on days 4/5 at 377+/-162U/ml for full-length rHu BChE and 574+/-143U/ml for truncated rHu BChE. These activity levels are orders of magnitude higher than 1.9U/ml of mouse BChE present in wild-type mouse serum. Thereafter, rHu BChE levels dropped rapidly and very little or no activity was detected in the serum 10 days post-virus administration. In conclusion, the present study demonstrates the potential of rAd-mediated Hu BChE gene therapy to counteract multiple lethal doses of chemical warfare nerve agent toxicity.
人血清丁酰胆碱酯酶（Hu BChE）是一种有望用于对抗化学战神经毒剂毒性、农药中毒和可卡因过量中毒的治疗药物。然而，从人血浆中大规模生产天然蛋白以及/或者获得适用于体内使用的重组蛋白存在困难，这阻碍了其广泛应用。通过体内递送和表达Hu BChE基因，这一限制或许可以得到解决。在本研究中，对编码全长和截短型rHu BChE的重组腺病毒（rAds）在小鼠体内的表达情况进行了测试。经腹腔注射这些rAds的小鼠未能表达rHu BChE。然而，对BChE基因敲除小鼠进行单次尾静脉注射这两种rAds后，可使血清中rHu BChE持续保持较高水平，其中全长rHu BChE在第4/5天达到峰值，为377±162U/ml，截短型rHu BChE为574±143U/ml。这些活性水平比野生型小鼠血清中存在的1.9U/ml小鼠BChE高出几个数量级。此后，rHu BChE水平迅速下降，在病毒给药后10天，血清中检测到的活性很低或没有活性。总之，本研究证明了rAd介导的Hu BChE基因疗法在对抗多致死剂量化学战神经毒剂毒性方面的潜力。
