体外诱导人类诱导性多能干细胞分化为造血干 / 祖细胞的研究简

本研究探讨体外诱导人诱导性多能干细胞（induced pluripotent stem cell,iPSC）分化为造血干/祖细胞的能力.在体外用小鼠骨髓基质细胞OP9与人类iPSC共培养的方法,将iPSC诱导分化为造血干/祖细胞;用流式细胞术检测造血干/祖细胞表面标志物的表达水平;用实时定量PCR检测分化过程中iPSC及造血干/祖细胞的相关基因mRNA表达水平的变化;用免疫磁珠法分离CD34＋造血干/祖细胞并进行半固体集落形成实验检测细胞的集落形成能力.结果表明,iPSC与OP9细胞共培养诱导造血分化的第4天即可观察到iPSC形态变化;流式细胞术检测显示,分化得到的细胞表达已知的造血干/祖细胞相关表面标志物CD34和CD43分子.在体外分化过程中多能性的标志基因Oct4的表达逐渐下降,造血相关转录因子Gata-2的表达逐渐升高,而Runx-1的表达量则呈波浪式变化,CD34表达量逐渐升高.集落培养14 d能够得到红系集落（CFU-E）,粒系集落（CFU-G）,巨核系集落（CFU-M）,粒-巨核系集落（CFU-GM）和混合系集落（CFU-GEMM）.结论：iPSC细胞能够在体外通过与OP9细胞共培养分化为造血干/祖细胞.     

Maturation of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes by Soluble Factors from Human Mesenchymal Stem Cells

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Impedance of Novel Therapeutic Technologies: The Case of Stem Cells

Embryonic stem cell (ES) technology has advanced considerably within the past three decades and has gained prominent distinction within the emerging field of regenerative medicine. As it now enters the nascent stages of clinical application, many hopes and expectations arise along with questions as to where the technology will go. This paper evaluates the technical and practical obstacles that must be overcome before it can fully translate into the clinical context, the existence of strong opposition to the technology, political and legal barriers that have impeded its progression, and the role of healthcare reform in creating new social and economic priorities. In contrast to the technological imperative, a driving force seeking to implement the most recent scientific advances into medical practice, we refer to such translational obstacles as “technological impedance.” Rather than expending inordinate effort to preserve existing systems that continue to possess major hurdles, we advocate fostering interdisciplinary approaches in the development of new generation platforms and embracing disruptive innovations that create solutions to technological impedance and move us forward in healthcare delivery. Clin Trans Sci 2012; Volume 5: 422–427     

非基因整合建立人诱导多能性干细胞方法的优化研究

诱导多能性干细胞（iPSC）技术具有临床应用前景,但iPSC的遗传稳定性和成瘤性阻碍了其可能的临床应用。非整合质粒（Episomal）方法无外源基因整合到宿主基因组上并且方法简单,适宜推广,是目前保证iPSC遗传安全性的最佳方案之一,但其诱导效率偏低,严重阻碍了其应用。本研究旨在优化Episomal方法,将脐血单个核细胞（CBMNC）重编程为诱导多能性干细胞（iPSC）,建立无基因整合的iPSC的高效生成技术体系,为以后建立疾病iPSC奠定基础。利用CBMNC,通过比较不同氧含量,诱导质粒,MNC培养方法和预刺激时间等条件对Episo—mal方法进行优化。结果表明：CBMNC采用红系培养液,培养8d,使用启动子为sFFV（spleen focus forming virus）的Episomal载体,在低氧（3％）条件下诱导,CBMNC重编程效率最高,可达到0．12％。通过分析最佳条件下供体细胞成分发现,表型为CD36＋CD71＋CD235alow的有核红细胞是重编程最主要的供体细胞来源。结论：本研究成功建立并优化出一种可推广的高效安全的,可以用于临床应用研究的iPSC诱导技术。     

An Overview of Current Position on Cell Therapy in Transfusion Science and Medicine: From Fictional Promises to Factual and Perspectives from Red Cell Substitution to Stem Cell Therapy

Stem cell therapy is a relatively novel field of investigation, in which either differentiated cells or stem cells capable of differentiation are transplanted into an individual with the objective of yielding specific cell types in the damaged tissue and consequently restoring its function. The most successful example of cell therapy is hematopoietic stem cell transplantation, leading to regeneration of a patient’s blood cells, now a widely established procedure for many oncologic and non–oncologic diseases. Innovative cell-based therapies are being developed to replace, regenerate or repair injured, absent, or diseased tissues and organs. However, cell therapy bioproducts are based on their inherent biological features such as proliferation, migratory, capability, plasticity, and capacity of self-renewal, posing serious challenges during such bioproduct development. The extraordinary promise of stem cells for future treatments of otherwise intractable diseases has raised great hope and expectations in patients, advocates, physicians, and researchers alike. However, despite thousands of scientific publications and research programs, increased efforts need to be put into the identification of the factors involved, biological mechanisms and materials that affect safety/ efficacy, and into the design of cost-effective methods for the harvesting, expansion, manipulation and purification of the cells.     

胰岛素样生长因子-1参与诱导小鼠诱导多潜能干细胞的研究

目的:观察胰岛素样生长因子-1(IGF-1)对小鼠诱导多潜能干(iPS)细胞诱导效率的影响。方法:将鼠胚成纤维细胞分为对照组和实验组,2组均予经典四因子的逆转录病毒载体感染,实验组在培养基里加入IGF-1,进行iPS细胞诱导,并对其进行鉴定。结果:对照组和实验组的iPS细胞诱导效率分别为(0.05±0.0002)%和(0.01±0.0005)%,所获iPS细胞为阳性。结论:IGF-1提高小鼠iPS细胞的诱导效率。     

Application of Epigenome‐Modifying Small Molecules in Induced Pluripotent Stem Cells

Recent breakthroughs in generating induced pluripotent stem cells (iPSCs) using four defined factors have revealed the potential utility of stem cells in biological research and clinical applications. However, the low efficiency and slow kinetics of reprogramming related to producing these cells and underlying safety issues, such as viral integration and genetic and epigenetic abnormalities of iPSCs, hamper the further application of iPSCs in laboratory and clinical settings. Previous studies have suggested that reprogramming efficiency can be enhanced and that reprogramming kinetics can be accelerated by manipulating epigenetic status. Herein, we review recent studies on the application of epigenome‐modifying small molecules in enhancing reprogramming and functionally replacing some reprogramming factors. We mainly focus on studies that have used small molecules to interfere with epigenome‐modifying enzymes, such as DNA methyltransferase, histone acetyltransferase, and histone methyltransferase. The potential use of these small molecules in inducing iPSCs and new ways to identify small molecules of higher potency and fewer side effects are also discussed.     

人参皂苷Rg1参与诱导小鼠多潜能干细胞的研究

目的:观察人参皂苷Rg1对鼠胚成纤维细胞(MEF)向诱导多潜能干细胞(iPSCs)诱导转化效率的影响。方法:采用经典四因子的逆转录病毒载体感染,在细胞感染后3 d内在MEF培养基里加入人参皂苷Rg1(0、0.3、1、3、10μg/mL),进行iPSCs诱导及鉴定。结果:人参皂苷Rg1(1μg/mL)组可明显提高iPSCs的诱导效率,诱导效率为(0.0450±0.0019)%,人参皂苷Rg1(0μg/mL)组为(0.0100±0.0033)%,所获iPSCs经鉴定为阳性。结论:人参皂苷Rg1可能在提高小鼠iPSCs的诱导效率方面发挥一定作用。     

诱导性多能干细胞在遗传性心脏病实验研究中的应用

人类诱导性多能干细胞(iPS 细胞)的建立是目前最重要的科技进展之一。近年来,iPS 细胞应用于遗传性心脏病细胞模型的建立,及其iPS 细胞治疗动物心梗模型成功,为探索遗传性心脏病的发病机制和治疗带来了光明前景。     

非整合型质粒重编程脐带血CD34~＋细胞形成诱导性多潜能干细胞的研究

本研究探索和优化非整合质粒的方法,将人脐带血来源的CD34＋（CB CD34＋）细胞进行重编程,建立无病毒的iPS技术体系。利用细胞核转染仪将质粒pEB-C5和pEB-Tg转入短暂培养后的CB CD34＋细胞中,使其进行重编程形成iPSC,14 d后观察到2×106CB CD34＋细胞中约有200个类似ES细胞特征的克隆出现,并对产生的iPSC进行体内外多能性鉴定及细胞核型检测。结果表明,重编程后的CB CD34＋细胞的多能性基因表达与ESC类似,细胞核型正常,外源基因无插入,且具有体内分化成三胚层的全能性。结论：利用非整合型质粒的方法重编程CB CD34＋细胞形成iPSC,该方法无外源基因插入、重复性好、操作简单、且效率较高,为建立相对安全的iPSC提供了一个行之有效的途径,为深入探索iPSC应用于临床药物的筛选、组织工程和再生医学研究等提供了很好的研究材料。     

诱导多能干细胞治疗大鼠糖尿病足溃疡的效果研究

目的观察局部移植异体诱导多能干细胞(induced pluripotent stem cell,IPSC)治疗糖尿病足溃疡SD大鼠的效果及其对外周血血管内皮生长因子(vascular endot growth factor,VEGF)的影响。方法取SD雄性大鼠40只,随机分为IPSC治疗组和对照组,分别对两组造糖尿病足溃疡模型。造模成功后IPSC治疗组在溃疡创面创缘肉膜层多点注射IPSC悬浊液,对照组在溃疡创面创缘肉膜层多点注射等体积Knockout DMEM培养液。观察比较两组治疗第1、5、10天溃疡面积及外周血VEGF水平。结果 40只SD雄性大鼠均成功造模。两组溃疡面积比较,治疗第1天差异无统计学意义(P0.05);治疗第5、10天IPSC治疗组溃疡面积均小于对照组,差异有统计学意义(P0.05)。两组外周血VEGF水平比较,治疗第1天差异无统计学意义(P0.05);治疗第5、10天IPSC治疗组外周血VEGF水平均高于对照组,差异有统计学意义(P0.05)。结论异体移植IPSC可促进糖尿病足溃疡SD大鼠溃疡愈合及局部新生血管形成。     

Mesenchymal Stem Cell-Based Therapy for Cardiovascular Disease: Progress and Challenges

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A Japanese Bioventure Company's Application of Stem Cell Technology in Regenerative Medicine

Regenerative medicine mediated by the transplantation of somatic stem cells and functional cells derived from induced pluripotent stem cells has great potential in the treatment of currently incurable diseases and thus has attracted significant public attention. To put this into practice, several functional cell lines were developed and laws regarding regenerative medicine were put in force in Japan. In this report, we introduce recent efforts of a bioventure company with special attention to the case of Healios K.K.     

Stem Cell‐Based Therapies for Ischemic Stroke: Preclinical Results and the Potential of Imaging‐Assisted Evaluation of Donor Cell Fate and Mechanisms of Brain Regeneration

Stroke is the second most common cause of death and is a major cause of permanent disability. Given the current demographic trend of an ageing population and associated increased risk, the prevalence of and socioeconomic burden caused by stroke will continue to rise. Current therapies are unable to sufficiently ameliorate the disease outcome and are not applicable to all patients. Therefore, strategies such as cell‐based therapies with mesenchymal stem cell (MSC) or induced pluripotent stem cell (iPSC) pave the way for new treatment options for stroke. These cells showed great preclinical promise despite the fact that the precise mechanism of action and the optimal administration route are unknown. To gain dynamic insights into the underlying repair processes after stem cell engraftment, noninvasive imaging modalities were developed to provide detailed spatial and functional information on the donor cell fate and host microenvironment. This review will focus on MSCs and iPSCs as types of widely used stem cell sources in current (bio)medical research and compare their efficacy and potential to ameliorate the disease outcome in animal stroke models. In addition, novel noninvasive imaging strategies allowing temporospatial in vivo tracking of transplanted cells and coinciding evaluation of neuronal repair following stroke will be discussed.     

Robust Cardiac Regeneration: Fulfilling the Promise of Cardiac Cell Therapy

PurposeWe review the history of cardiac cell therapy, highlighting lessons learned from initial adult stem cell (ASC) clinical trials. We present pluripotent stem cell–derived cardiomyocytes (PSC-CMs) as a leading candidate for robust regeneration of infarcted myocardium but identify several issues that must be addressed before successful clinical translation.MethodsWe conducted an unstructured literature review of PubMed-listed articles, selecting the most comprehensive and relevant research articles, review articles, clinical trials, and basic or translation articles in the field of cardiac cell therapy. Articles were identified using the search terms adult stem cells, pluripotent stem cells, cardiac stem cell, and cardiac regeneration or from references of relevant articles, Articles were prioritized and selected based on their impact, originality, or potential clinical applicability.FindingsSince its inception, the ASC therapy field has been troubled by conflicting preclinical data, academic controversies, and inconsistent trial designs. These issues have damaged perceptions of cardiac cell therapy among investors, the academic community, health care professionals, and, importantly, patients. In hindsight, the key issue underpinning these problems was the inability of these cell types to differentiate directly into genuine cardiomyocytes, rendering them unable to replace damaged myocardium. Despite this, beneficial effects through indirect paracrine or immunomodulatory effects remain possible and continue to be investigated. However, in preclinical models, PSC-CMs have robustly remuscularized infarcted myocardium with functional, force-generating cardiomyocytes. Hence, PSC-CMs have now emerged as a leading candidate for cardiac regeneration, and unpublished reports of first-in-human delivery of these cells have recently surfaced. However, the cardiac cell therapy field's history should serve as a cautionary tale, and we identify several translational hurdles that still remain. Preclinical solutions to issues such as arrhythmogenicity, immunogenicity, and poor engraftment rates are needed, and next-generation clinical trials must draw on robust knowledge of mechanistic principles of the therapy.ImplicationsThe clinical transplantation of functional stem cell–derived heart tissue with seamless integration into native myocardium is a lofty goal. However, considerable advances have been made during the past 2 decades. Currently, PSC-CMs appear to be the best prospect to reach this goal, but several hurdles remain. The history of adult stem cell trials has taught us that shortcuts cannot be taken without dire consequences, and it is essential that progress not be hurried and that a worldwide, cross-disciplinary approach be used to ensure safe and effective clinical translation.     

造血干细胞与基因治疗

国际上临床基因治疗从1991年开始,至今有关的基础研究已取得很大进展,但一些重大难题尚未解决。例如:基因转染的载体、目的基因体内转染的靶向性、目的基因在体内表达的水平和时间的调控以及有治疗效果基因的选择和寻找等。美国几例ADA基因治疗病例,其带有目的基因的细胞在病人体内维持时间太短。为了使目的基因能在病人体内长期或永久地表达,必须选一种能在体内自我更新和自我维持的永不消亡的细胞,作为目的基因的宿主细胞。于是,造血干细胞便成为最理想的目的基     

Stem cell technologies in regenerative medicine

The IIR Life Sciences conference on stem cell technologies in regenerative medicine was held in London, UK on 11 – 12 July 2002. The conference covered not only technologies but also ethical/regulatory and financial aspects of embryonic stem (ES) cell therapy. An excellent introduction to embryonic stem cells was given by Prof. William Kridel (Ferghana Partners, London, UK). Details of basic technologies are not described as they are covered in a detailed report on cell therapy [1]. Due to limitation of space only a selected few of the seventeen presentations are reported here.     

The 6th Annual Meeting of the UK Cord Blood and Adult Stem Cell Group

The meeting was established in 1999 by the UK cord blood immunobiology group. Over the last 6 years the annual meeting has attracted multidiscipline participants interested in the immunobiology of cord blood and the immunology of maternal fetal engraftment from universities, hospitals and cord blood banks throughout the UK and Europe. The 6th annual meeting was held in the Life Bioscience Centre ‘Centre for Life’ in association with the University of Newcastle upon Tyne. The purpose of this meeting was to bring together the most up-to-date scientific results, both the clinical applications and immunobiology of cord blood stem cells. The meeting, although relatively small-scale, was clearly focused on specific topics and was highly interactive between scientists and clinicians. The meeting was introduced and chaired by Professor Anne Dickinson, University of Newcastle upon Tyne, UK.     

我国造血干细胞基础研究的新进展兼论干细胞可塑性

1995年以来我国造血干细胞工程与相关的生物学领域的研究发展迅速。有关造血干 祖细胞基因表达的研究 ,上海国家人类基因组研究中心陈竺、陈赛娟等为正常和急性白血病人骨髓造血干祖细胞cDNA文库的基因表达建立了一套先进的工作体系。他们在许多白血病细胞系的干 祖细胞中发现了 30 0个新的相关基因。中山大学医学院李树浓、黄绍良等从人的桑葚期胚胎干细胞成功地诱导出造血细胞等。北京输血研究所裴雪涛等从成人和胎儿的骨髓分离出成年源干细胞 ,又进一步诱导分化为骨、软骨、脂肪和神经原细胞等。他们成功地构建了胎儿和成人间充质干细胞cDNA扣除文库 ,获得了胎儿和成人间充质干细胞的差异表达基因及在胎儿特异表达基因。中国医学科学院天津血液学研究所、国家血液学重点实验室赵春华等证实从胚胎胰腺、骨髓和肝脏中都可以分离出人间充质干细胞 ,又证明G CSF可以使输注的间充质干细胞在体内促造血重建。北京基础医学研究所毛宁等的实验不支持间充质干细胞可以“横向分化”。最近他们发现小鼠胚胎干细胞的体外分化重现了胚胎早期造血发生的生物学程序以及Smad5基因调控在胚胎造血发生中的必要性和多样性 ,又表明其上游配体TGF beta家族分子在胚胎发生中的作用和特点。本文针对干细胞可塑性研究作了评