心脏基因治疗的外源性控制：含有糖皮质激素反应元件启动子的表达盒经腺病毒和腺相关病毒转导后心肌转基因表达受调控的证据。

Exogenous control of cardiac gene therapy: evidence of regulated myocardial transgene expression after adenovirus and adeno-associated virus transfer of expression cassettes containing corticosteroid response element promoters.

作者信息

Lee L Y, Zhou X, Polce D R, El-Sawy T, Patel S R, Thakker G D, Narumi K, Crystal R G, Rosengart T K

机构信息

Division of Pulmonary and Critical Care Medicine and Department of Cardiothoracic Surgery, The New York Presbyterian Hospital-Weill Medical College of Cornell University, New York, NY, USA.

出版信息

J Thorac Cardiovasc Surg. 1999 Jul;118(1):26-4, discussion 34-5. doi: 10.1016/S0022-5223(99)70137-6.

DOI:10.1016/S0022-5223(99)70137-6

PMID:10384181

Abstract

OBJECTIVE

Because of the relative inaccessibility of the heart for repeated gene therapy, it would be useful to regulate the expression of transgenes delivered in a single dose of a gene therapy vector. Incorporation into the vector of a regulatable promoter that is responsive to pharmacologic agents that are widely used and well tolerated in clinical practice represents such a control strategy.

METHODS

A replication-deficient adenovirus or an adeno-associated virus containing a chimeric promoter composed of 5 glucocorticoid response elements and the murine thrombopoietin complementary DNA (AdGRE.mTPO or AAVGRE.mTPO) was administered to the hearts of Sprague-Dawley rats. Platelet levels were evaluated as a reporter of transgene activity with or without dexamethasone. For comparison, rats received a control adenovirus vector, AdCMV.mTPO or AdCMV.Null, and the control adeno-associated virus vector AAVCMV.luc, which encodes for the firefly luciferase (luc) gene.

RESULTS

Platelet elevation in the AdGRE.mTPO group peaked 4 days after dexamethasone administration, with a return to baseline 1 week after the initial corticosteroid dose. Subsequent dexamethasone administration at 2 and 4 weeks resulted in similar but progressively decreased responses. The AAVGRE.mTPO group had 5 peak platelet levels to a minimum of 2.2-fold with respect to baseline without diminution with subsequent dexamethasone administrations out to 169 days. In contrast, the AdCMV.Null and AAVCMV.luc groups demonstrated no increase in platelet counts and the AdCMV.mTPO group demonstrated a slow rise to a single peak platelet count independent of dexamethasone administration.

CONCLUSION

It may be possible to control on demand the expression of a gene transferred to the heart. This strategy should be useful in cardiac gene therapy.

摘要

目的

由于心脏相对难以进行重复基因治疗，因此调节单次给予基因治疗载体所传递的转基因的表达将是有用的。将对临床实践中广泛使用且耐受性良好的药理剂有反应的可调节启动子整合到载体中，代表了这样一种控制策略。

方法

将含有由5个糖皮质激素反应元件和小鼠血小板生成素互补DNA组成的嵌合启动子的复制缺陷型腺病毒或腺相关病毒（AdGRE.mTPO或AAVGRE.mTPO）施用于Sprague-Dawley大鼠的心脏。在有或没有地塞米松的情况下，评估血小板水平作为转基因活性的报告指标。为了进行比较，大鼠接受对照腺病毒载体AdCMV.mTPO或AdCMV.Null，以及编码萤火虫荧光素酶（luc）基因的对照腺相关病毒载体AAVCMV.luc。

结果

AdGRE.mTPO组的血小板升高在给予地塞米松后4天达到峰值，在初始皮质类固醇剂量后1周恢复到基线水平。在第2周和第4周随后给予地塞米松导致类似但逐渐降低的反应。AAVGRE.mTPO组的血小板峰值水平相对于基线最低为2.2倍，在随后长达169天的地塞米松给药中没有降低。相比之下，AdCMV.Null和AAVCMV.luc组的血小板计数没有增加，而AdCMV.mTPO组的血小板计数缓慢上升至单个峰值，与地塞米松给药无关。