再生医学方法在糖尿病足治疗中的应用

糖尿病足(DF)是糖尿病常见的并发症之一.糖尿病周围神经或末梢血管病变合并感染和损伤常导致足溃疡的产生,严重者可因下肢坏疽导致截肢,甚至危及生命.糖尿病足的高患病率和低治愈率给糖尿病患者和社会带来了极大的负担.再生医学是一种通过干细胞移植、组织工程化皮肤等方法,有效地促进糖尿病足创面愈合,是一种具有潜力的治疗方法.组织...     

糖尿病足的干细胞治疗

糖尿病足是糖尿病的主要慢性并发症之一.足部外伤合并感染导致溃疡、坏疽,甚至使患者面临截肢的危险,严重地影响糖尿病患者的生活质量.干细胞治疗能有效促进新血管生成、促进创面愈合,并治疗缺血性下肢血管病变,是治疗糖尿病足的新方法.文章对干细胞治疗糖尿病足如骨髓干细胞移植、外周血干细胞移植、脐带血干细胞移植及真皮间充质干细胞移...     

神经生长因子在糖尿病足创面组织中表达相关性的研究进展

动物实验研究证实神经生长因子（NGF）促进创面组织血管生成、血管内皮细胞再生,促进缺血创面的愈合及糖尿病创面的愈合。通过NGF在糖尿病创面表达改变的研究,有助于NGF促进糖尿病创面愈合机制的探讨,为糖尿病足创面愈合提供新的理论依据。     

骨髓间充质干细胞移植治疗糖尿病足过程中血管内皮生长因子的表达

背景：目前已有研究证明骨髓间充质干细胞移植治疗糖尿病足能够获得良好的效果。 目的：评价骨髓间充质干细胞移植治疗糖尿病足溃疡的效果以及血管内皮生长因子的表达情况。 方法：应用文献检索的方法获取骨髓间充质干细胞移植治疗糖尿病足及血管内皮生长因子表达的相关研究文献,对符合研究标准的文献进行深入的数据分析,文章选取骨髓间充质干细胞移植治疗糖尿病足的实验研究和临床应用进行分析,实验研究中,建立大鼠糖尿病足溃疡模型,给予骨髓间充质干细胞移植治疗,观察创面溃疡的愈合情况,并分析血管内皮生长因子的表达情况。临床应用研究中,对应用骨髓间充质干细胞移植治疗糖尿病足的患者进行观察随访,观察创面溃疡的愈合情况以及不良反应发生情况。 结果与结论：实验研究显示骨髓间充质干细胞移植治疗糖尿病足创面溃疡的愈合快于常规治疗,但是与正常足溃疡愈合相比仍较慢,且移植治疗后血管内皮生长因子的表达升高,但是低于正常足溃疡对照的水平。临床应用研究显示糖尿病足溃疡患者经骨髓间充质干细胞移植治疗后,创面溃疡基本均可完全愈合,且无心、脑血管疾病、肝肾功能损伤以及出凝血时间改变等不良反应发生。     

皮下移植骨髓间充质干细胞修复大鼠糖尿病足溃疡

背景：糖尿病足溃疡严重威胁患者的健康甚至生命,目前缺乏良好的治疗手段,而干细胞疗法在组织再生和创面修复方面展现出独特的优势及潜力。 目的：评价骨髓间充质干细胞经创缘皮下移植对大鼠糖尿病足溃疡的治疗效果。 方法：全骨髓贴壁法体外培养Wistar大鼠骨髓间充质干细胞至第3代,经DAPI标记。36只雄性Wistar大鼠随机分成骨髓间充质干细胞移植组、正常足溃疡对照组、糖尿病足溃疡对照组,大鼠糖尿病经腹腔注射链脲佐菌素诱导,所有大鼠在双后足背上切取一3 mm×7 mm矩形全层皮肤制成足溃疡模型。于骨髓间充质干细胞移植后第2,5,8,11天评估各组大鼠创面愈合情况及相关蛋白和基因水平的表达情况。 结果与结论：正常足溃疡对照组的创面愈合率大于骨髓间充质干细胞移植组和糖尿病足溃疡对照组,但后2组之间无差异。冰冻切片发现骨髓间充质干细胞移植组荧光强度和区域在第5天达到高峰。苏木精-伊红染色显示第5天正常足溃疡对照组肉芽组织最厚,骨髓间充质干细胞移植组比糖尿病足溃疡对照组厚。免疫组化发现骨髓间充质干细胞移植组CD31平均小血管数目在第8天和第11天比糖尿病足溃疡对照组多(P < 0.05);骨髓间充质干细胞移植组平均Ki-67阳性细胞数在各时间点均比糖尿病足溃疡对照组多(P < 0.01)。ELISA和RT-PCR结果均显示,正常足溃疡对照组血管内皮细胞生长因子表达水平较骨髓间充质干细胞移植组、糖尿病足溃疡对照组高。第5天和第8天骨髓间充质干细胞移植组表达水平显著高于糖尿病足溃疡对照组(P < 0.01)。说明骨髓间充质干细胞经创缘皮下移植明显促进大鼠糖尿病足溃疡的愈合,此疗效可能是通过促进创伤中血管内皮细胞生长因子的表达实现的。     

羊膜负载表皮干细胞促进糖尿病大鼠创面的愈合

背景:表皮干细胞作为皮肤组织的特异性干细胞,具有强大增殖及多向分化潜能,与创面修复紧密相关。近期研究表明糖尿病皮肤创面愈合过程中表皮干细胞数量减少、活性降低是导致其创面难愈的重要原因。目的:观察表皮干细胞在糖尿病大鼠创面愈合中的作用。方法:分离培养及鉴定SD大鼠表皮干细胞,并以BrdU标记。建立糖尿病SD大鼠创面模型,抽签法随机分为3组:表皮干细胞组创面移植羊膜负载BrdU标记的表皮干细胞;羊膜组创面移植羊膜;空白对照组创面未给予干预。观察创面愈合情况、计算创面愈合率,苏木精-伊红及免疫组织化学SP法检测创面愈合组织中BrdU及增殖细胞核抗原表达。用图像分析软件测量阳性细胞积分吸光度平均值。结果与结论:表皮干细胞组治疗后7d创面缩小明显,治疗后14d创面基本愈合,创面愈合率明显高于羊膜组、空白对照组(P0.01)。表皮干细胞组创面及新生表皮中可见BrdU阳性细胞,而另两组皮肤创面组织中始终未见BrdU阳性细胞。各组创面组织中可见增殖细胞核抗原阳性细胞表达,但表皮干细胞组的阳性细胞积分吸光度平均值与羊膜组、空白对照组比较差异有显著性意义(P0.01)。结果证实糖尿病大鼠创面愈合过程中表皮干细胞与创缘表皮移行、创面的上皮化有直接关联,可有效促进其创面愈合。     

不同来源干细胞移植治疗糖尿病足分析

背景：糖尿病足患者多伴有肢体远端血管缺血,临床治疗效果一直不是很满意,自体干细胞移植是近几年来兴起的一种安全有效治疗方法。 目的：对干细胞治疗糖尿病足研究的文献资料趋势进行多层次探讨分析。 方法：以电子检索方式对CNKI数据库学术期刊2003/2011收录有关干细胞治疗糖尿病足研究的文献进行分析,采用检索词为“干细胞;糖尿病足”,运用数据库的分析功能和Excel软件图表的功能分析数据特征。 采用自体骨髓干细胞、自体造血干细胞或脐血干细胞等方法移植治疗糖尿病足,将细胞通过肌内注射或血管输注的方式注入下肢缺血部位,治疗后比较肢体疼痛、冷感、皮肤温度、间歇性跛行、溃疡愈合程度和血管造影等结果,判断细胞移植的治疗效果。 结果与结论：在CNKI数据库学术期刊2003/2011收录的文献中,共检索到125篇与干细胞治疗糖尿病足研究相关的文献。文献量呈逐年上升趋势,文献的主要内容显示了糖尿病足、干细胞移植、移植等。干细胞移植以自体细胞来源为主,主要应用骨髓干细胞和造血干细胞两种。通过干细胞移植可以使糖尿病足患者的症状减轻,疼痛得到缓解,下肢血管造影有不同程度的新生侧支血管形成,对改善糖尿病足患者的下肢缺血起到一定作用。     

脐带间充质干细胞促血管新生在治疗下肢缺血中的研究与应用

背景：干细胞在一定诱导条件下可分化成为血管性内皮细胞,促进缺血下肢血管新生和有效循环的建立,改善糖尿病远端缺血肢体供血。目的：概述脐带间充质干细胞生物学特性、促血管新生的机制,探讨脐带间充质干细胞修复神经病变及慢性创面等基础研究和临床研究现状。方法：检索2000至2015 年PubMed 数据库、维普中文科技数据库及万方数据相关文献。英文检索词为“stem cells transplantation,umbilical Cord Mesenchymal Stem Cell,diabetic angiopathies”;中文检索词为“干细胞移植,脐带间充质干细胞,糖尿病血管病变”。结果与结论：与目前外周血干细胞及骨髓间充质干细胞移植相比,脐带间充质干细胞来源更广泛,采集方便,扩增能力强,无免疫原性,不存在伦理学争议,成为促血管新生和基因治疗缺血性疾病的理想靶细胞和种子细胞。脐带间充质干细胞能够分化为血管内皮细胞和成纤维细胞参与创面愈合,也可促进神经营养因子表达,促进缺血组织神经再生,并通过旁分泌与自分泌细胞因子、抗炎及免疫调节等参与受损组织的组织修复,加快溃疡面愈合,对于改善糖尿病下肢缺血、修复糖尿病周围神经病变和促进慢性溃疡创面愈合等治疗中具有广阔的应用前景。与单纯的干细胞移植比较,脐带间充质干细胞联合细胞因子基因治疗可进一步提高干细胞存活率及促进血管新生。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

毛囊干细胞在皮肤伤口修复中的促进作用

背景：毛囊干细胞来源于皮肤、毛发,数量极其可观,取材后无严重的并发症和免疫原性,可供自体移植,是最容易获取的干细胞来源之一。目的：综述毛囊干细胞促进皮肤伤口修复的作用因素,以期为该领域研究提供有效的实验依据。方法：应用计算机以“毛囊干细胞、皮肤修复、再生医学、组织工程”或“hair follicle stem cell,skin repairing,regenerative medicine,tissue engineering”为检索词检索CNKI 和 PubMed 数据库1999年1月至2014年12月发表的关于毛囊干细胞促进皮肤伤口修复的文章,最终选择45篇文章进行综述。结果与结论：毛囊干细胞作为一种容易获得、数量可观、使用较为安全以及具有分化潜能的成体干细胞,可以通过皮肤早期血管化、表皮及附属器官的再生、信号通路作用及转录因子调节等方面的影响,促进皮肤伤口的修复,能为再生医学及组织工程研究提供良好的种子细胞。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

组织工程皮肤移植过程中白细胞介素10和肿瘤坏死因子α的表达

背景:白细胞介素10和肿瘤坏死因子α在异体异种皮肤移植局部免疫与排斥反应中发挥了重要作用。但在组织工程人工皮肤移植过程中局部皮肤组织内白细胞介素10和肿瘤坏死因子α的表达情况目前尚不清楚。目的:采用表皮干细胞联合脱细胞真皮构建人工皮肤并移植修复兔全层皮肤缺损创面,观察创面修复效果和局部皮肤组织白介素10与肿瘤坏死因子α的表达变化。方法:将体外培养的人表皮干细胞或角质细胞接种到脱细胞真皮支架中,构建组织工程人工皮肤;取新西兰白兔常规制作背部全层皮肤缺损创面随机分为4组,表皮干细胞组、角质细胞组用含表皮干细胞或角质细胞的组织工程皮肤移植于皮肤缺损创面;脱细胞真皮组移植单纯脱细胞真皮;对照组创面空置。观察创面修复情况,局部炎症反应,创面愈合时间。各组分别于术后7d在部分创面取材观察组织形态和白细胞介素10与肿瘤坏死因子α表达。结果与结论:含表皮干细胞的人工皮肤移植后创面愈合良好,局部炎症反应轻微,无出血、积脓、坏死,创面愈合时间较角质细胞组明显缩短。白细胞介素10在各组均有表达,其中表皮干细胞组表达最强,角质细胞组次之,脱细胞真皮组和对照组最弱。肿瘤坏死因子α在各组也均有表达,其中角质细胞组表达最强,表皮干细胞组次之,脱细胞真皮组和对照组较弱。说明以表皮干细胞作为种子细胞联合脱细胞真皮构建人工皮肤可用有效促进皮肤缺损创面的修复治疗,创面修复过程中局部皮肤组织内白细胞介素10和肿瘤坏死因子的表达变化可能是其取得较好效果的主要机制之一。     

Using stem cells in skin regeneration: possibilities and reality

Tissue-engineered skin has a long history of clinical applications, yet current treatments are not capable of completely regenerating normal, uninjured skin. Nonetheless, the field has experienced a tremendous development in the past 10 years, encountering the summit of tissue engineering (TE) and the arising of stem cell research. Since then, unique features of these cells such as self-renewal capacity, multi-lineage differentiation potential, and wound healing properties have been highlighted. However, a realistic perspective of their outcome in skin regenerative medicine applications is still absent. This review intends to discuss the directions that adult and embryonic stem cells (ESCs) can take, strengthening the skin regeneration field. Distinctively, a critical overview of stem cells' differentiation potential onto skin main lineages, along with a highlight of their participation in wound healing mechanisms, is herein provided. We aim to compile and review significant work to allow a better understanding of the best skin TE approaches, enabling the embodiment of the materialization of a new era in skin regeneration to come, with a conscious overview of the current limitations.     

表皮干细胞在组织工程创面修复中的应用

背景：随着细胞生物学、分子生物学技术、组织工程学的快速发展,探寻组织工程化皮肤创面覆盖物的“种子细胞”的研究逐渐增多。 目的：总结表皮干细胞的生物学特性,探讨其在皮肤创面修复过程中的再生作用与临床应用价值。 方法：应用计算机检索CNKI和PubMed数据库中2002-07/2011-12关于表皮干细胞修复皮肤损伤研究的文章,以“表皮干细胞,创面修复,组织工程,皮肤”或“epidermal stem cells,tissue engineering skin,wound surface”为检索词进行检索。选择文章内容与表皮干细胞修复皮肤损伤研究进展有关的文章,同一领域文献则选择近期发表或发表在权威杂志文章。初检得到129篇文献,根据纳入标准选择28篇文献进行综合分析。 结果与结论：表皮干细胞是表皮发生、分化和创面修复的基础,其正常增殖分化是维持皮肤正常组织结构和细胞内环境稳定的基本要求,也是皮肤组织工程理想的种子细胞。对烧伤、创伤等大面积皮肤缺损的治疗,对皮肤疾病的细胞疗法、基因治疗等方面都有很好的应用前景。表皮细胞的体外培养是复合人工皮肤组织工程学研究的先决条件。随着对表皮干细胞分离、纯化和培养技术的不断完善,可达到迅速构建表皮层的目的。但表皮干细胞的应用研究仍需要进一步的探索。     

壳多糖组织工程皮肤治疗糖尿病足性溃疡

目的比较壳多糖组织工程皮肤、亲水性敷料（多爱肤）和传统纱布对糖尿病足性溃疡治疗疗效。方法将53例糖尿病足皮肤溃疡患者随机分为多爱肤组、壳多糖组及常规治疗组,以溃疡愈合率及平均愈合时间为观察指标。结果多爱肤组愈合率与常规治疗组比较,差异有统计学意义（P〈0.05）;壳多糖组愈合率与多爱肤组相比,差异有统计学意义（P〈0.05）;常规治疗组与多爱肤组及壳多糖组比较,平均愈合时间差异有统计学意义（P〈0.05）,多爱肤组与壳多糖组比较,平均愈合时间无统计学差异（P〉0.05）。结论多爱肤组可提高溃疡愈合率,缩短平均愈合时间;壳多糖组织工程皮肤与多爱肤相比较能显著提高溃疡愈合率。     

IFATS collection: Using human adipose-derived stem/stromal cells for the production of new skin substitutes

The ability to harvest and culture stem cell populations from various human postnatal tissues is central to regenerative medicine applications, including tissue engineering. The discovery of multipotent mesenchymal stem cells within the stromal fraction of adipose tissue prompted their use for the healing and reconstruction of many tissues. Here, we examined the influence of adipose-derived stem/stromal cells (ASCs) on skin's regenerative processes, from a tissue engineering perspective. Using a self-assembly approach, human skin substitutes were produced. They featured a stromal compartment containing human extracellular matrix endogenously produced from either dermal fibroblasts or adipose-derived stem/stromal cells differentiated or not toward the adipogenic lineage. Human keratinocytes were seeded on each stroma and cultured at the air-liquid interface to reconstruct a bilayered skin substitute. These new skin substitutes, containing an epidermis and a distinctive stroma devoid of synthetic biomaterial, displayed characteristics similar to human skin. The influence of the type of stromal compartment on epidermal morphogenesis was assessed by the evaluation of tissue histology, the expression of key protein markers of the epidermal differentiation program (keratin [K] 14, K10, transglutaminase), the expression of dermo-epidermal junction components (laminins, collagen VII), and the presence of basement membrane and hemidesmosomes. Our findings suggest that adipose-derived stem/stromal cells could usefully substitute dermal fibroblasts for skin reconstruction using the self-assembly method. Finally, by exploiting the adipogenic potential of ASCs, we also produced a more complete trilayered skin substitute consisting of the epidermis, the dermis, and the adipocyte-containing hypodermis, the skin's deepest layer. Disclosure of potential conflicts of interest is found at the end of this article.     

Regulation of the Matrix Microenvironment for Stem Cell Engineering and Regenerative Medicine

The extracellular matrix (ECM) microenvironment consists of structural and functional molecules. The ECM relays both biochemical and biophysical cues to and from the cells to modulate cell behavior and function. The biophysical cues can be engineered and applied to cells by means of spatial patterning, matrix rigidity, and matrix actuation. Tissue engineering strategies that utilize ECMs to direct stem cell organization and lineage specification show tremendous potential. This review describes the technologies for modulating ECM spatial patterning, matrix rigidity, chemical composition, and matrix actuation. The role of ECMs in vascular tissue engineering is then discussed as a model of tissue engineering and regenerative medicine.     

Static Magnetic Field (SMF) as a Regulator of Stem Cell Fate – New Perspectives in Regenerative Medicine Arising from an Underestimated Tool

Tissue engineering and stem cell-based therapies are one of the most rapidly developing fields in medical sciences. Therefore, much attention has been paid to the development of new drug-delivery systems characterized by low cytotoxicity, high efficiency and controlled release. One of the possible strategies to achieve these goals is the application of magnetic field and/or magnetic nanoparticles, which have been shown to exert a wide range of effects on cellular metabolism. Static magnetic field (SMF) has been commonly used in medicine as a tool to increase wound healing, bone regeneration and as a component of magnetic resonance technique. However, recent data shed light on deeper mechanism of SMF action on physiological properties of different cell populations, including stem cells. In the present review, we focused on SMF effects on stem cell biology and its possible application as a tool for controlled drug delivery. We also highlighted the perspectives, in which SMF can be used in future therapies in tissue engineering due to its easy application and a wide range of possible effects on cells and organisms.     

Concise review: Transplantation of human hematopoietic cells for extracellular matrix protein deficiency in epidermolysis bullosa

The skin is constantly exposed to environmental insults and requires effective repair processes to maintain its protective function. Wound healing is severely compromised in people with congenital absence of structural proteins of the skin, such as in dystrophic epidermolysis bullosa, a severe congenital mechanobullous disorder caused by mutations in collagen type VII. Remarkably, stem cell transplantation can ameliorate deficiency of this skin-specific structural protein in both animal models and in children with the disorder. Healthy donor cells from the hematopoietic graft migrate to the injured skin; simultaneously, there is an increase in the production of collagen type VII, increased skin integrity, and reduced tendency to blister formation. How hematogenous stem cells from bone marrow and cord blood can alter skin architecture and wound healing in a robust, clinically meaningful way is unclear. We review the data and the resulting hypotheses that have a potential to illuminate the mechanisms for these effects. Further modifications in the use of stem cell transplantation as a durable source of extracellular matrix proteins may make this regenerative medicine approach effective in other cutaneous and extracutaneous conditions.