干细胞移植治疗心血管系统疾病的体内示踪影像学研究

干细胞移植已被广泛地应用于细胞死亡相关性心脏病的治疗。胚胎干细胞（embryonic stem cells）、骨骼成肌细胞（skeletal myoblasts）、骨髓来源的干细胞（bone marrow—derived stem cells）及心脏固有的干细胞（cardiac resident stem cells）等几个类型细胞均被试验,并且临床前期试验显示对于急性和慢性心肌损伤,     

干细胞移植临床应用研究进展

干细胞(stem cells,SCs)通常是指具有通过复制和向特异细胞系分化而具有自我更新能力的细胞.干细胞按分化能力可分为几群.一类细胞由受精卵子代细胞进化为8分化桑葚胚而来,能分化为各种器官组织细胞,被称为"全能"干细胞;如胚胎干细胞(ESCs)可生成所有胚层的细胞,包括内胚层、中胚层和外胚层的细胞;后天诱导产生的成体干细胞(adult stem cells,ASCs)就只能生成有限亚群的细胞.另一种分类方法是基于来源细胞所处的进化阶段分类,源于胚胎的胚胎干细胞和后天诱导产生的ASCs.     

人骨髓间充质干细胞诱导分化的内皮细胞相关鉴定及活性检测

目的探讨将人骨髓间充质干细胞（Human bone mesenchymal stem cells,HBMCs）诱导为内皮细胞（endothelial cells,ECs）的可行性。方法将HBMCs分离、培养后,加入诱导因子定向诱导为ECs,并对细胞进行鉴定和细胞活性检测。结果经鉴定,HBMCs在特定环境下分化为了ECs,而且后者与人正常血管ECs的细胞活性无显著差异性。结论以HBMCs诱导的ECs作为种子细胞,具有可行性。     

神经生长因子对骨髓基质细胞成骨分化影响的研究进展

神经生长因子（nerve growth factor,NGF）的来源十分广泛,可以由不同来源的细胞所分泌,组成结构认识的较为清楚,其促进成骨的作用近年来成为研究的热点。骨髓基质细胞（bone marrow—derived mesenchymal stem cells,BMSCs）向成骨细胞的分化潜能也为众多研究所认可,本文就NGF促进BMSCs成骨作用的可行性作一综述。     

间充质干细胞对恶性肿瘤影响的研究进展

<正>间充质干细胞(mesenchymal stem cells,MSCs)是一种起源于中胚层发育早期的具有全能干细胞特点的造血干细胞以外的另一类干细胞,因具有自我更新、多向分化以及免疫调节等功能,临床已被广泛应用于脊髓损伤、糖尿病足和一些自身免疫性疾病的治疗。     

人参皂苷Rg1通过miR-138-5p/SIRT1轴诱导骨髓间充质干细胞向髓核样细胞增殖分化

目的 探讨人参皂苷Rg1诱导大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)向髓核样细胞(nucleus pulposus cells,NPCs)分化的机制.方法 从成年SD大鼠中分离培养BMSCs.通过CCK-8法检测不同浓度人参皂苷Rg1(0,2.5,5,10...     

中药调节PMOP成骨与成脂分化平衡的研究进展

绝经后骨质疏松症发病风险逐年上升,其发病与骨平衡的破坏有关,成骨细胞功能衰减、骨形成不足,最终导致净骨量丢失。而骨形成又与骨髓间充质干细胞(Bone marrow mesenchymal stem cells,BMSCs)的成骨分化和成脂分化关系密切,其分化受多条信号通路调控。本文主要对中药调控骨髓间充质干细胞的分化及其机制进行总结与分析。     

间充质干细胞膜微粒的临床应用研究进展

由于干细胞具有自我更新和分化为其他类型细胞的能力,因此,干细胞在临床上的应用也越来越广泛。而间充质干细胞(mesenchymal stem cells,MSCs)不仅具有自我更新的能力,而且具有多向分化潜能,在不同的诱导条件下可以分化为不同组织[1],同时,MSCs来源方便,易于分离、培养、扩增和纯化,多代扩增后仍具有干细胞特性,不存在免疫排斥,体外基因转染率高并能稳定     

维生素C可提高iPS细胞诱导效率

诱导多能性干细胞（induced pluripotent stem cells，iPS cells）是具有胚胎干细胞特性的一种细胞。由体细胞诱导而来，可作为胚胎干细胞最好的替代品用于科学研究和临床治疗。但iPS细胞的成功诱导比较复杂．诱导效率一直是科学界的难题，通常每万个细胞才能诱导成功一例iPS细胞。     

In vitro and in vivo induction of bone formation based on adeno-associated virus-mediated BMP-7 gene therapy using human adipose-derived mesenchymal stem cells

Aim： To determine whether adeno-associated virus （AAV）-2-mediated, bone morphogenetic protein （BMP）-7-expressing human adipose-derived mesenchymal stem cells （ADMS） cells would induce bone formation in vitro and in vivo. Methods： ADMS cells were harvested from patients undergoing selective suction-assisted lipectomy and transduced with AAV carrying the human BMP-7 gene. Non-trans- duced cells and cells transduced with AAV serotype 2 carrying the enhanced green fluorescence protein gene served as controls. ADMS cells were qualitatively assessed for the production of BMP-7 and osteocalcin, and subjected to alkaline phosphatase （ALP） and Chinalizarin staining. A total of 2.5×10^6 cells mixed with type I collagen were implanted into the hind limb of severe combined immune-deficient （SCID） mice and subjected to a histological analysis 3 weeks post implantation. Results： Transfection of the ADMS cells achieved an efficiency of 99% at d 7. Transduction with AAV2-BMP-7 induced the expression of BMP-7 until d 56, which was markedly increased by d 7. The cells were positively stained for ALP. Osteocalcin production and matrix mineralization further con- firmed that these cells differentiated into osteoblasts and induced bone formation in vitro. A histological examination demonstrated that implantation of BMP-7- expressing ADMS cells could induce new bone formation in vivo. Conclusion： The present in vitro and in vivo study demonstrated that human ADMS cells would be a promising source of autologous mesenchymal stem cells for BMP gene therapy and tissue engineering.     

Genetically manipulated adult stem cells for wound healing

New knowledge of the signal controls and activities of adult stem cells (ASCs) involved in wound repair have led to extensive investigation of the topical delivery of biomacromolecules and multipotent stem cells to injured tissues for scar-less regeneration. The transplantation of genetically recombinant stem cells, which have roles as both therapeutics and carriers for gene delivery to wound sites, represents an attractive strategy for wound treatment. Here, we compare viral and non-viral vectors and three-dimensional scaffold-based transfection strategies in terms of their biosafety, recombinant efficiency and influence on the differentiation of ASCs, to indicate the future direction of the application of recombinant ASCs in wound treatment.     

Stem cell therapy for neurologic disorders: therapeutic potential of adipose-derived stem cells

There is growing evidence to suggest that reservoirs of stem cells may reside in several types of adult tissue. These cells may retain the potential to transdifferentiate from one phenotype to another, presenting exciting possibilities for cellular therapies. Recent discoveries in the area of neural differentiation are particularly exciting given the limited capacity of neural tissue for intrinsic repair and regeneration. Adult adipose tissue is a rich source of mesenchymal stem cells, providing an abundant and accessible source of adult stem cells. These cells have been termed adipose derived stem cells (ASC). The characterization of these ASCs has defined a population similar to marrow-derived and skeletal muscle-derived stem cells. The success seen in differentiating ASC into various mesenchymal lineages has generated interest in using ASC for neuronal differentiation. Initial in vitro studies characterized the morphology and protein expression of ASC after exposure to neural induction agents. Additional in vitro data suggests the possibility that ASCs are capable of neuronal activity. Progress in the in vitro characterization of ASCs has led to in vivo modeling to determine the survival, migration, and engraftment of transplanted ASCs. While work to define the mechanisms behind the transdifferentiation of ASCs continues, their application to neurological diseases and injuries should also progress. The subject of this review is the capacity of adipose derived stem cells (ASC) for neural transdifferentiation and their application to the treatment of various neurologic disorders.     

Adipose-derived stem cells decolonize skin Staphylococcus aureus by enhancing phagocytic activity of peripheral blood mononuclear cells in the atopic rats

Staphylococcus aureus (S. aureus) is known to induce apoptosis of host immune cells and impair phagocytic clearance, thereby being pivotal in the pathogenesis of atopic dermatitis (AD). Adipose-derived stem cells (ASCs) exert therapeutic effects against inflammatory and immune diseases. In the present study, we investigated whether systemic administration of ASCs restores the phagocytic activity of peripheral blood mononuclear cells (PBMCs) and decolonizes cutaneous S. aureus under AD conditions. AD was induced by injecting capsaicin into neonatal rat pups. ASCs were extracted from the subcutaneous adipose tissues of naïve rats and administered to AD rats once a week for a month. Systemic administration of ASCs ameliorated AD-like symptoms, such as dermatitis scores, serum IgE, IFN-γ⁺/IL-4⁺ cell ratio, and skin colonization by S. aureus in AD rats. Increased FasL mRNA and annexin V⁺/7-AAD⁺ cells in the PBMCs obtained from AD rats were drastically reversed when co-cultured with ASCs. In contrast, both PBMCs and CD163⁺ cells bearing fluorescent zymosan particles significantly increased in AD rats treated with ASCs. Additionally, the administration of ASCs led to an increase in the mRNA levels of antimicrobial peptides, such as cathelicidin and β-defensin, in the skin of AD rats. Our results demonstrate that systemic administration of ASCs led to decolonization of S. aureus by attenuating apoptosis of immune cells in addition to restoring phagocytic activity. This contributes to the improvement of skin conditions in AD rats. Therefore, administration of ASCs may be helpful in the treatment of patients with intractable AD.     

Generation of reactive oxygen species in adipose-derived stem cells: friend or foe?

INTRODUCTION: Reactive oxygen species (ROS) participate in cellular apoptosis and are involved in pathophysiological etiology of degenerative diseases. However, recent studies suggest that ROS at low levels may play a pivotal role as second messengers and activate normal cellular processes. Intracellular ROS increase the proliferation, migration, and regenerative potential of adipose-derived stem cells (ASCs). In contrast, manipulations that diminish intracellular ROS levels interfere with normal ASC function. ROS generation therefore acts like a double-edged sword. AREAS COVERED: This review discusses the following research questions: i) Do ROS stimulate or suppress ASCs? ii) How are ROS generated from ASCs? iii) Which function(s) is/are regulated by intracellular ROS generation? In addition, the antioxidant/antiapoptotic effect of ASCs is briefly introduced. EXPERT OPINION: Whether ROS is harmful or beneficial is primarily a question of dosage. Low or moderate ROS generation increases the proliferation, migration and regenerative potential of ASCs. Therefore, it is beneficial to expose ASCs to moderate oxidative stress during manipulation. The addition of a ROS donor in culture can reduce the cost for the expansion of ASCs and a ROS preconditioning can enhance the regenerative potential of ASCs.     

3D organoids derived from the small intestine: An emerging tool for drug transport research

Small intestine in vitro models play a crucial role in drug transport research. Although conventional 2D cell culture models, such as Caco-2 monolayer, possess many advantages, they should be interpreted with caution because they have relatively poor physiologically reproducible phenotypes and functions. With the development of 3D culture technology, pluripotent stem cells (PSCs) and adult somatic stem cells (ASCs) show remarkable self-organization characteristics, which leads to the development of intestinal organoids. Based on previous studies, this paper reviews the application of intestinal 3D organoids in drug transport mediated by P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) and multidrug resistance protein 2 (MRP2). The advantages and limitations of this model are also discussed. Although there are still many challenges, intestinal 3D organoid model has the potential to be an excellent tool for drug transport research.     

黄芪多糖对兔脂肪来源的间充质干细胞体外增殖的影响

目的黄芪多糖(APS)对兔脂肪来源的间充质干细胞(ASCs)体外增殖的作用。方法提取兔ASCs进行培养,设实验组和对照组,实验组加入不同浓度APS注射液,对照组加常规培养液,四甲基偶氮唑盐(MTT)法观察细胞的增殖率,比较两组之间的差异。结果 APS浓度为1.95～3.90μg/mL时,对ASCs的增殖无明显影响(P>0.05);而浓度为7.80～1 000μg/mL时,对ASCs的增殖有明显抑制作用(P<0.01);在一定浓度范围内(25～100μg/mL),浓度对细胞增殖的影响不大,而与培养的时间有关,随着作用时间的延长,对ASCs的抑制作用更加明显。结论低浓度APS对兔ASCs体外增殖无影响;高浓度APS对ASCs有明显的抑制作用。     

Bone biomimetic microenvironment induces osteogenic differentiation of adipose tissue-derived mesenchymal stem cells

A critical strategy for tissue engineering is to provide the signals necessary for tissue regeneration by mimicking the tissue microenvironment. In this study, we mimicked (1) the bone chemical and the physical microenvironment by fabricating a three-dimensional nanocomposite scaffold composed of biphasic calcium phosphates (BCP) coated with a nanocomposite layer of polycaprolactone (PCL) and hydroxyapatite nanoparticles (nHA) (BCP/PCL-nHA)), and (2) the bone's biological microenvironment by co-culturing with primary human osteoblasts (HOBs), and then investigated their effects on osteogenic differentiation of adipose tissue-derived stem cells (ASCs). In comparison with the ASCs cultured alone on BCP scaffolds that were coated only with PCL, early osteogenic differentiation of ASCs was induced by either seeding ASCs on BCP/PCL-nHA scaffolds or by co-culturing with HOBs; the combination of BCP/PCL-nHA scaffold and HOBs resulted in the synergistic enhancement of osteogenic gene expression. Moreover, we found that BCP/PCL-nHA scaffolds induced early osteogenic differentiation of ASCs through integrin-α2 and an extracellular signal-regulated kinase (ERK) signaling pathway. FROM THE CLINICAL EDITOR: The authors mimicked the physico-chemical environment of bone by fabricating a nanocomposite scaffold, and then co-cultured it with human osteoblasts. Demonstrated enhancement of osteogenic gene expression and early osteogenic differentiation of adipose tissue derived stem cells were found using this approach.     

Generation of reactive oxygen species in adipose-derived stem cells: friend or foe?

Introduction: Reactive oxygen species (ROS) participate in cellular apoptosis and are involved in pathophysiological etiology of degenerative diseases. However, recent studies suggest that ROS at low levels may play a pivotal role as second messengers and activate normal cellular processes. Intracellular ROS increase the proliferation, migration, and regenerative potential of adipose-derived stem cells (ASCs). In contrast, manipulations that diminish intracellular ROS levels interfere with normal ASC function. ROS generation therefore acts like a double-edged sword.

Areas covered: This review discusses the following research questions: i) Do ROS stimulate or suppress ASCs? ii) How are ROS generated from ASCs? iii) Which function(s) is/are regulated by intracellular ROS generation? In addition, the antioxidant/antiapoptotic effect of ASCs is briefly introduced.

Expert opinion: Whether ROS is harmful or beneficial is primarily a question of dosage. Low or moderate ROS generation increases the proliferation, migration and regenerative potential of ASCs. Therefore, it is beneficial to expose ASCs to moderate oxidative stress during manipulation. The addition of a ROS donor in culture can reduce the cost for the expansion of ASCs and a ROS preconditioning can enhance the regenerative potential of ASCs.     

Oxidative stress on progenitor and stem cells in cardiovascular diseases

There is accumulating evidence that reactive oxygen species (ROS) play major roles in the initiation and progression of cardiovascular dysfunction associated with diseases such as hyperlipidemia, diabetes mellitus, hypertension, ischemic heart disease, and chronic heart failure. ROS produced by migrating inflammatory cells as well as vascular cells (endothelial cells, vascular smooth muscle cells, and adventitial fibroblasts) have distinct functional effects on each cell type. These effects include cell growth, apoptosis, migration, inflammatory gene expression and matrix regulation. ROS, through regulating vascular cell function, can play a central role in normal vascular physiology, and contribute substantially to the development of cardiovascular diseases. Excessive production of ROS is an essential mechanism underlying the pathogenesis of endothelial dysfunction and cardiovascular disease. Stem cells hold great promise for tissue repair and regenerative medicine, and endothelial progenitor cells (EPC) play a significant role in neovascularization of ischemic tissue. Recent studies have shown that cardiovascular risk factors such as hypertension, hypercholesterolemia, diabetes and cigarette smoking are inversely correlated with EPC number and function. Understanding the mechanisms, that regulate EPC function may provide new insights into the pathogenesis of vasculogenesis and may promote development of specific therapies to prevent ROS production and ultimately correct EPC dysfunction. We have demonstrated the angiotensin II receptor blockers improve EPC dysfunction through antioxidative mechanisms. In the present review, we describe our current understanding of the contributions of oxidative stress to progenitor and stem cell dysfunction in cardiovascular disease and focus on the potential mechanisms that underlie oxidative stress-induced damage of progenitor and stem cells.     

Gene-modified adult stem cells regenerate vertebral bone defect in a rat model

Vertebral compression fractures (VCFs), the most common fragility fractures, account for approximately 700,000 injuries per year. Since open surgery involves morbidity and implant failure in the osteoporotic patient population, a new minimally invasive biological solution to vertebral bone repair is needed. Previously, we showed that adipose-derived stem cells (ASCs) overexpressing a BMP gene are capable of inducing spinal fusion in vivo. We hypothesized that a direct injection of ASCs, designed to transiently overexpress rhBMP6, into a vertebral bone void defect would accelerate bone regeneration. Porcine ASCs were isolated and labeled with lentiviral vectors that encode for the reporter gene luciferase (Luc) under constitutive (ubiquitin) or inductive (osteocalcin) promoters. The ASCs were first labeled with reporter genes and then nucleofected with an rhBMP6-encoding plasmid. Twenty-four hours later, bone void defects were created in the coccygeal vertebrae of nude rats. The ASC-BMP6 cells were suspended in fibrin gel (FG) and injected into the bone void. A control group was injected with FG alone. The regenerative process was monitored in vivo using microCT, and cell survival and differentiation were monitored using tissue specific reporter genes and bioluminescence imaging (BLI). The surgically treated vertebrae were harvested after 12 weeks and subjected to histological and immunohistochemical (against porcine vimentin) analyses. In vivo BLI detected Luc-expressing cells at the implantation site over a 12-week period. Beginning 2 weeks postoperatively, considerable defect repair was observed in the group treated with ASC-BMP6 cells. The rate of bone formation in the stem cell-treated group was two times faster than that in the FG-treated group, and bone volume at the end point was 2-fold compared to the control group. Twelve weeks after cell injection the bone volume within the void reached the volume measured in native vertebrae. Immunostaining against porcine vimentin indicated that the ASC-BMP6 cells contributed to new bone formation. Here we show the potential of injections of BMP-modified ASCs to repair vertebral bone defects in a rat model. Our results could pave the way to a novel approach for the biological treatment of traumatic and osteoporosis-related vertebral bone injuries.