Lai Chao-Han, Wang Kuan-Chieh, Kuo Cheng-Hsiang, Lee Fang-Tzu, Cheng Tsung-Lin, Chang Bi-Ing, Yang Yu-Jen, Shi Guey-Yueh, Wu Hua-Lin
Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Cardiovascular Research Center, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Cardiovascular Research Center, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Tourism Management, College of Recreation and Health Management, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan.
Atherosclerosis. 2017 Jul;262:62-70. doi: 10.1016/j.atherosclerosis.2017.03.024. Epub 2017 Mar 18.
Thrombomodulin (TM), through its lectin-like domain (TMD1), sequesters proinflammatory high-mobility group box 1 (HMGB1) to prevent it from engaging the receptor for advanced glycation end product (RAGE) that sustains inflammation and tissue damage. Our previous study demonstrated that short-term treatment with recombinant TM containing all the extracellular domains (i.e., rTMD123) inhibits HMGB1-RAGE signaling and confers protection against CaCl-induced AAA formation. In this study, we attempted to further optimize TM domains, as a potential therapeutic agent for AAA, using the recombinant adeno-associated virus (AAV) vector.
The therapeutic effects of recombinant TMD1 (rTMD1) and recombinant AAV vectors carrying the lectin-like domain of TM (rAAV-TMD1) were evaluated in the CaCl-induced AAA model and angiotensin II-infused AAA model, respectively.
In the CaCl-induced model, treatment with rTMD1 suppressed the tissue levels of HMGB1 and RAGE, macrophage accumulation, elastin destruction and AAA formation, and the effects were comparable to a mole-equivalent dosage of rTMD123. In the angiotensin II-infused model, a single intravenous injection of rAAV-TMD1 (10 genome copies), which resulted in a persistently high serum level of TMD1 for at least 12 weeks, effectively attenuated AAA formation with suppression of HMGB1 and RAGE levels and inhibition of proinflammatory cytokine production, macrophage accumulation, matrix metalloproteinase activities and oxidative stress in the aortic wall.
These findings corroborate the therapeutic potential of the TM lectin-like domain in AAA. The attenuation of angiotensin II-infused AAA by one-time delivery of rAAV-TMD1 provides a proof-of-concept validation of its application as potential gene therapy for aneurysm development.
血栓调节蛋白（TM）通过其凝集素样结构域（TMD1）隔离促炎的高迁移率族蛋白B1（HMGB1），以防止其与晚期糖基化终产物受体（RAGE）结合，后者可维持炎症和组织损伤。我们之前的研究表明，用包含所有细胞外结构域的重组TM（即rTMD123）进行短期治疗可抑制HMGB1-RAGE信号传导，并对氯化钙诱导的腹主动脉瘤（AAA）形成起到保护作用。在本研究中，我们试图使用重组腺相关病毒（AAV）载体进一步优化TM结构域，作为AAA的一种潜在治疗药物。
分别在氯化钙诱导的AAA模型和输注血管紧张素II的AAA模型中评估重组TMD1（rTMD1）和携带TM凝集素样结构域的重组AAV载体（rAAV-TMD1）的治疗效果。
在氯化钙诱导的模型中，rTMD1治疗可抑制HMGB1和RAGE的组织水平、巨噬细胞积聚、弹性蛋白破坏和AAA形成，其效果与摩尔当量剂量的rTMD123相当。在输注血管紧张素II的模型中，单次静脉注射rAAV-TMD1（10个基因组拷贝）可使血清TMD1水平持续升高至少12周，有效减轻AAA形成，同时抑制HMGB1和RAGE水平，并抑制主动脉壁中促炎细胞因子的产生、巨噬细胞积聚、基质金属蛋白酶活性和氧化应激。
这些发现证实了TM凝集素样结构域在AAA中的治疗潜力。一次性递送rAAV-TMD1减轻输注血管紧张素II诱导的AAA，为其作为动脉瘤发展的潜在基因治疗应用提供了概念验证。
