Department of Cardiology & Pneumology, Campus Benjamin Franklin, Charité-University Medicine Berlin, Hindenburgdamm 30, Berlin, Germany.
Circulation. 2009 Dec 8;120(23):2358-66. doi: 10.1161/CIRCULATIONAHA.108.845339. Epub 2009 Nov 23.
Group B coxsackieviruses (CVBs) are the prototypical agents of acute myocarditis and chronic dilated cardiomyopathy, but an effective targeted therapy is still not available. Here, we analyze the therapeutic potential of a soluble (s) virus receptor molecule against CVB3 myocarditis using a gene therapy approach.
We generated an inducible adenoviral vector (AdG12) for strict drug-dependent delivery of sCAR-Fc, a fusion protein composed of the coxsackievirus-adenovirus receptor (CAR) extracellular domains and the carboxyl terminus of human IgG1-Fc. Decoy receptor expression was strictly doxycycline dependent, with no expression in the absence of an inducer. CVB3 infection of HeLa cells was efficiently blocked by supernatant from AdG12-transduced cells, but only in the presence of doxycycline. After liver-specific transfer, AdG12 (plus doxycycline) significantly improved cardiac contractility and diastolic relaxation compared with a control vector in CVB3-infected mice if sCAR-Fc was induced before infection (left ventricular pressure 59+/-3.8 versus 45.4+/-2.7 mm Hg, median 59 versus 45.8 mm Hg, P<0.01; dP/dt(max) 3645.1+/-443.6 versus 2057.9+/-490.2 mm Hg/s, median 3526.6 versus 2072 mm Hg/s, P<0.01; and dP/dt(min) -2125.5+/-330.5 versus -1310.2+/-330.3 mm Hg/s, median -2083.7 versus -1295.9 mm Hg/s, P<0.01) and improved contractility if induced concomitantly with infection (left ventricular pressure 76.4+/-19.2 versus 56.8+/-10.3 mm Hg, median 74.8 versus 54.4 mm Hg, P<0.05; dP/dt(max) 5214.2+/-1786.2 versus 3011.6+/-918.3 mm Hg/s, median 5182.1 versus 3106.6 mm Hg/s, P<0.05), respectively. Importantly, hemodynamics of animals treated with AdG12 (plus doxycycline) were similar to uninfected controls. Preinfection induction of sCAR-Fc completely blocked and concomitant induction strongly reduced cardiac CVB3 infection, myocardial injury, and inflammation.
AdG12-mediated sCAR-Fc delivery prevents cardiac dysfunction in CVB3 myocarditis under prophylactic and therapeutic conditions.
B 组柯萨奇病毒（CVBs）是急性心肌炎和慢性扩张型心肌病的典型病原体，但仍缺乏有效的靶向治疗方法。在这里，我们使用基因治疗方法分析了可溶性（s）病毒受体分子对 CVB3 心肌炎的治疗潜力。
我们生成了一种诱导型腺病毒载体（AdG12），用于严格依赖药物的 sCAR-Fc 的递送，sCAR-Fc 是由柯萨奇病毒-腺病毒受体（CAR）细胞外结构域和人 IgG1-Fc 的羧基末端组成的融合蛋白。诱饵受体的表达严格依赖于强力霉素，在没有诱导剂的情况下没有表达。上清液从 AdG12 转导的细胞中可有效阻断 HeLa 细胞的 CVB3 感染，但仅在存在强力霉素的情况下才有效。在肝特异性转移后，如果在感染前诱导 sCAR-Fc（AdG12（加强力霉素）），与感染 CVB3 的小鼠中的对照载体相比，AdG12（加强力霉素）可显著改善心脏收缩功能和舒张松弛功能（左心室压 59+/-3.8 与 45.4+/-2.7mmHg，中位数 59 与 45.8mmHg，P<0.01；dP/dt(max)3645.1+/-443.6 与 2057.9+/-490.2mmHg/s，中位数 3526.6 与 2072mmHg/s，P<0.01；和 dP/dt(min)-2125.5+/-330.5 与-1310.2+/-330.3mmHg/s，中位数-2083.7 与-1295.9mmHg/s，P<0.01），并且如果同时诱导感染，则可改善收缩功能（左心室压 76.4+/-19.2 与 56.8+/-10.3mmHg，中位数 74.8 与 54.4mmHg，P<0.05；dP/dt(max)5214.2+/-1786.2 与 3011.6+/-918.3mmHg/s，中位数 5182.1 与 3106.6mmHg/s，P<0.05）。重要的是，用 AdG12（加强力霉素）治疗的动物的血液动力学与未感染的对照组相似。在感染前诱导 sCAR-Fc 的完全阻断和同时诱导强烈减少了 CVB3 感染、心肌损伤和炎症。
AdG12 介导的 sCAR-Fc 递送达可预防预防性和治疗性条件下 CVB3 心肌炎的心脏功能障碍。
