Xenotransplantation of ex vivo gene trandected cardiomyocytes

本实验将胎鼠心肌细胞移植到结扎冠状动脉造成心肌梗死的大鼠体内。在梗死区，移植的胎儿心肌细胞因缺血坏死，而在正常区和梗死区交界区，移植的胎儿心肌细胞存活，无超急性排斥反应。此外，少量免疫抑制剂（环孢素5 mg/kg）可使供者细胞存活30天以上。我们认为胚胎心肌细胞的异种移植在心力衰竭的治疗中是有用的，基因转导技术极大地扩展了免疫治疗包括恶性肿瘤在内的各种疾病的潜在可行性。非病毒载体系统的一个关键障碍是相对较差的转导/表达效率，这中断了它们在临床应用中的真实的应用。然而，基于Epstein-Barr病毒（EBV）的附加型质粒载体与各种递送载体组合在各种人类细胞中带来非常强的表达。利用该载体系统将干扰素-β基因导入肿瘤细胞，观察基因操作的抗肿瘤效果。通过用基于EBV的载体转染获得了对肿瘤细胞生长的显著抑制，而通过常规质粒载体转移相同的基因导致中等抑制效果。非病毒手段与EBV为基础的质粒载体提供了新的策略，适用于免疫基因治疗的遗传操作。

We examined xenotransplantion of fetal murine cardiomyocytes to rats, which was made myocardial infarction with coronary artery ligated. In the infracted area, transplanted fetal cardiomyocytes was necrosis due to ischemia, but are alive without hyper-acute rejection in the border zone of normal and infracted area. In addition a little immuno-suppressive agent (cyclosporine 5mg/kg) made donor cells alive over thirty days. We think xenotransplantation of fetal cardiomyocytes are useful for therapy of heart failure.The gene tranduction technologies have greatly expand the potential feasibility of immunotheapy against various disorders including malignancy. A critical impediment of non-viral vector system is the relatively poor Transduction/expression efficiency, which interrupts their real applications to clinical usage. However, the Epstein-Barr virus(EBV)-based episomal plasmid vectors in combination with various delivery vehicles bring very-strong expression in variety of human cells. We tried gene transduction of interferon-β gene to tumor cells with this vector system, and examined anti-tumor effect of gene manipulation. Remarkable suppression of tumor cells growth was obtained by transfection with the EBV-based vector, while transfer of same gene by a conventional Plasmid vector resulted in moderate suppressive effect. Non-viral means equipped with EBV-based plasmid vector offer novel strategies of genetic manipulation applicable to immuno-gene therapy.