组织工程学--21世纪面临的机遇与挑战

组织工程学是近20年来医学生命科学领域最具进展与挑战性的前沿科技领域之一,被誉为“一场意义深远的医学革命”、“再生医学的新时代”,标志着复制再生组织与器官的时代的来临!由于它具有修复创伤、重建功能、挽救生命、提高生存质量所特有的优势及巨大的社会、经济价值,而倍受国际学术界及各国政府的高度关注与支持。目前国际上组织工程皮肤、组织工程软骨已有产品面世,并得到美国FDA的批准,国际上已成立了近百家组织工程公司,我国多家大学、研究单位亦相继成立了组织工程研发中心或组织工程公司。目前不但可以构建组织工程化组织,而且复杂生命器官组织工程化构建亦已在国内外积极展开,同时,一些组织工程化组织已初步应用于临床并取得了可喜的临床疗效,显示出组织工程技术可喜的局面、巨大的生命力与宏伟的远景。然而,组织工程学是一门新兴学科,是跨领域、多学科参与合作的边缘学科,目前的工作仅仅是初始,还有大量基本科学问题尚待阐明,大量技术难题尚待攻克;光明与困难共存,机遇与挑战同在;应不失时机抓住机遇,开拓创新,迎接挑战,全力打造组织工程技术的新时代,使组织工程技术能够尽早造福于人类。     

皮肤组织工程研究的新进展

组织工程学是以细胞生物学、工程学和材料学相结合，在体外或体内构建组织或器官替代物，用于修复、维持或改善机体形态和功能的一门新兴的交叉学科^[1]。组织工程皮肤为急性或慢性皮肤损伤提供了全新的治疗理念。然而，目前的皮肤替代物仅仅是结构的模仿，且存在构建时间长、修复有限、无皮肤附件及瘢痕形成等缺陷。     

面向21世纪的组织工程学研究趋势与策略

经过20余年的飞速发展，组织工程研究已进入一个非常关键的发展时期。当前组织工程研究的热点、重点与组织工程发展的初期有很大不同，已正在逐步走向围绕临床应用与产品开发的研究方向上来。本文结合本期骨科组织工程的专题论文，指出基础研究须与临床应用、产业化紧密结合，组织或器官的构建须由单一、简单的方式向复杂仿生化、智能化方向转变，组织工程组织的初步临床应用、安全性评价、组织工程相关产品的产业化开发等方面的研究是今后组织工程发展的趋势与方向，并对相关研究的策略进行评述。     

兔组织工程肌的构建与研究

目的　探讨用同种异体兔成肌细胞和小肠黏膜下层( small instestinel submucosa,SIS)复合,体外培养构建兔组织工程肌。　方法　取出生7d内幼兔四肢肌组织,经多步酶消化法与差速贴壁法获得足量、纯净成肌细胞,用Brd U标记,与SIS体外复合培养构建组织工程肌,植入15只异体兔体内修复腓肠肌1.5 cm×1.0 cm大小的骨骼肌缺损作为实验组;用单纯SIS修复对侧同样骨骼肌缺损作为对照组。术后4、6和8周各处死5只动物取材,行大体和组织学观察、局部细胞免疫定量分析和免疫组织化学检测。　结果　体外培养成肌细胞与SIS均复合良好,体内植入4周见材料与周围肌组织接合紧密,周围炎性反应明显;6周和8周材料开始部分降解,炎性反应逐渐减轻。局部细胞免疫定量分析显示实验组和对照组4、6周评分与8周评分比较有统计学意义( P<0 .0 5 )。实验组4、6和8周均可见材料周围新生肌组织形成,Brd U及肌球蛋白免疫组织化学染色阳性,对照组染色结果呈阴性。　结论　成肌细胞与SIS复合构建的组织工程肌,植入体内可存活、增殖并形成新的肌组织     

Tissue engineering: a 21st century solution to surgical reconstruction

Tissue engineering has emerged as a rapidly expanding approach to address the organ shortage problem. It is an "interdisciplinary field that applies the principles and methods of engineering and the life sciences toward the development of biological substitutes that can restore, maintain, or improve tissue function." Much progress has been made in the tissue engineering of structures relevant to cardiothoracic surgery, including heart valves, blood vessels, myocardium, esophagus, and trachea.     

21世纪循证外科学:困境、挑战和机遇

困境岁末年初,大家总会静下心来回顾过去、展望未来。每年Nature,Science、ASCO评出的10大医学进展,美国时代周刊和伦敦泰晤士报医学头条,中国医学论坛报首页新闻,充斥我们视野的词汇多是“分子靶向”、“抗血管生成”、“干细胞”、“RNAi”、“基因关联分析”、“疫苗研究”、“药物临床试验”、“FDA”……;与此同时手术戒毒被叫停,移植手术需准入,肿瘤微创切除受质疑,癌肿手术从过去切除范围不断扩大到今天理性控制、功能保留、强调生活质量及作为多学科治疗的有机组成。“外科”、“手术”和“切除”这一类字眼似乎逐渐被医学领域…     

Transplantation in the 21st century

Remarkable results have been achieved in the field of organ transplantation over the past 40 years, perhaps inconceivable in the pioneering days of the 1950's. Factors which have contributed to these results include better immuno-suppression, matching for HLA, better preservation, and resolution of most of the technical problems associated with organ transplantation. Nevertheless, major problems still remain to be resolved. Chronic rejection leads to a steady attrition of all solid organ grafts. In addition, the penalty of our more potent immunosuppression is becoming evident with the ever-increasing incidence of cardiovascular disease and malignancy in long-surviving patients. These problems would be solved by the achievement of tolerance to an organ graft. However, there will never be sufficient human organs or tissues to meet the demand, which has led to a revival of interest in xenotransplantation, but enormous immunological and infectious problems have still to be resolved. New immunosuppressive agents, both drugs and biological agents, are being evaluated continually in the laboratory and some are going on to clinical trials. The explosion in molecular biology is allowing new approaches, such as genetic engineering, to be taken in the achievement of tolerance as well as solving some of the problems of xenotransplantation. Cloning of tissues and perhaps even organs may become possible in the future. Undoubtedly transplantation will look very different in twenty years' time as we enter the "Dawn of the New Millennium".     

Smallpox in the 21st century

The viral disease, smallpox, was well known through the end of the 20th Century. Because it has been eradicated from natural populations, the present clinical experience with managing the disease is limited. Similarly, research in the pathophysiology, treatment, and prevention of the disease has recently become a priority. Concerns regarding smallpox as a weapon of bioterrorism have led to the implementation of a new prophylactic vaccine program, a renewal in variola vaccine research, and treatment regimens against variola infection.