首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 780 毫秒
1.
Orthotopic liver transplantation (OLT) is the only proven effective treatment for both end-stage and metabolic liver diseases. Hepatocyte transplantation is a promising alternative for OLT, but the lack of available donor livers has hampered its clinical application. Hepatocyte-like cells (HLCs) differentiated from many multi-potential stem cells can help repair damaged liver tissue. Yet almost suitable cells currently identified for human use are difficult to harvest and involve invasive procedures. Recently, a novel mesenchymal stem cell derived from human menstrual blood (MenSC) has been discovered and obtained easily and repeatedly. In this study, we examined whether the MenSCs are able to differentiate into functional HLCs in vitro. After three weeks of incubation in hepatogenic differentiation medium containing hepatocyte growth factor (HGF), fibroblast growth factor-4 (FGF-4), and oncostain M (OSM), cuboidal HLCs were observed, and cells also expressed hepatocyte-specific marker genes including albumin (ALB), α-fetoprotein (AFP), cytokeratin 18/19 (CK18/19), and cytochrome P450 1A1/3A4 (CYP1A1/3A4). Differentiated cells further demonstrated in vitro mature hepatocyte functions such as urea synthesis, glycogen storage, and indocyanine green (ICG) uptake. After intrasplenic transplantation into mice with 2/3 partial hepatectomy, the MenSC-derived HLCs were detected in recipient livers and expressed human ALB protein. We also showed that MenSC-derived HLC transplantation could restore the serum ALB level and significantly suppressed transaminase activity of liver injury animals. In conclusion, MenSCs may serve as an ideal, easily accessible source of material for tissue engineering and cell therapy of liver tissues.  相似文献   

2.
Embryonic stem(ES)cells are widely used for different purposes,including gene targeting,cell therapy,tissue repair,organ regeneration,and so on.However,studies and applications of ES cells are hindered by ethical issues regarding cell sources.To circumvent ethical disputes,great efforts have been taken to generate ES cell-like cells,which are not derived from the inner cell mass of blastocyst-stage embryos.In 2006,Yamanaka et al.first reprogrammed mouse embryonic fibroblasts into ES cell-like cells called induced pluripotent stem(iPS)cells.About one year later,Yamanaka et al.and Thomson et al.independently reprogrammed human somatic cells into iPS cells.Since the first generation of iPS cells,they have now been derived from quite a few different kinds of cell types.In particular,the use of peripheral blood facilitates research on iPS cells because of safety,easy availability,and plenty of cell sources.Now iPS cells have been used for cell therapy,disease modeling,and drug discovery.In this review,we describe the generations,applications,potential issues,and future perspectives of iPS cells.  相似文献   

3.
In this study, we examined 96 undergraduate non-science majors’ conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before and after instruction. Two goals of the instruction were to: (1) help students construct accurate scientific ideas, and (2) enhance their reasoning about socioscientific issues. The course structure included interactive lectures, case discussions, hands-on activities, and independent projects. Overall, students’ understandings of stem cells, stem cell research, and cloning increased from pre-test to post-test. For example, on the post-test, students gained knowledge concerning the age of an organism related to the type of stem cell it possesses. However, we found that some incorrect ideas that were evident on the pre-test persisted after instruction. For example, before and after instruction several students maintained the idea that stem cells can currently be used to produce organs.  相似文献   

4.
INTRODUCTION Congestive heart failure is the end stage of manycardiovascular diseases. Myocardial infarction (MI)is a life-threatening event that may cause suddencardiac death and heart failure. Despite considerableadvances in diagnosis and treatment of heart disease,cardiac dysfunction after MI is still the majorworldwide cardiovascular disorder. Damaged myo-cardium after acute MI is gradually replaced by fi-brotic noncontractile cells to form scar tissue. Thedeveloping ventricul…  相似文献   

5.
Stem cells constitute an important class of cells in the body that have the ability to perpetuate themselves and remain in an uncommitted state by a process of self-renewal as well as to specialize into new cell types. Their ability to differentiate into multiple cell types marks the tremendous potential of stem cells for tissue repair and organ regeneration. Realization of this potential is rapidly opening up unexplored avenues for curing several ailments including diabetes and neurodegenerative diseases. However, very little is understood about the basic biology of stem cells. For example, what are the biochemical tags that allow us to identify stem cell? Which are the signaling pathways that regulate their function? How does the environment (niche) influence major decisions made by stem cell? Is stem cell therapy the end to all woes, or is there a flip side to the story? This article aims to give an overview of the current status of stem cell research and raises some alarming issues related to stem cell-based therapies.  相似文献   

6.

Objective  

Human embryonic stem cells (hESCs) have recently been reported as an unlimited source of mesenchymal stem cells (MSCs). The present study not only provides an identical and clinically compliant MSC source derived from hESCs (hESC-MSCs), but also describes the immunomodulative effects of hESC-MSCs in vitro and in vivo for a carbon tetrachloride (CCl4)-induced liver inflammation model.  相似文献   

7.
目的体外分离胰腺干细胞,选择最佳培养条件探索胰腺干细胞在体外环境下向β细胞的分化情况.方法取SD大鼠胰腺组织,胶原酶消化,密度梯度离心获得纯化的胰腺导管上皮细胞.采用分步诱导法诱导胰腺导管上皮细胞向胰岛β细胞分化;用胰岛素释放实验检测胰岛功能,免疫荧光法检测nestin,PDX-1,CK-19,CK-20胰岛素及胰高血糖素等的表达.结果胰腺消化培养6～12h,可看到胰腺导管上皮细胞贴壁生长,通过4步诱导培养,nestin阳性细胞快速生长,并可分泌胰岛素.结论体外分离的成人胰岛前体细胞,在诱导因子的作用下,胰腺干细胞可定向分化为β细胞,有望应用于糖尿病的治疗.  相似文献   

8.
To examine the effects of co-culture with bone marrow mesenchymal stem cells on expansion of hematopoietic stem/progenitor cells and the capacities of rapid neutrophil engraftment and hematopoietic reconstitution of the expanded cells, we expanded mononuclear cells (MNCs) and CD34+/c-kit+ cells from mouse bone marrow and transplanted the expanded cells into the irradiated mice. MNCs were isolated from mouse bone marrow and CD34+/c-kit+ cells were selected from MNCs by using MoFlo Cell Sorter. MNCs and CD34+/c-kit+ cells were co-cultured with mouse bone marrow-derived mesenchymal stem cells (MSCs) under a two-step expansion. The expanded cells were then transplanted into sublethally irradiated BDF1 mice. Results showed that the co-culture with MSCs resulted in expansions of median total nucleated cells, CD34+ cells, GM-CFC and HPP-CFC respectively by 10.8-, 4.8-, 65.9- and 38.8-fold for the mononuclear cell culture, and respectively by 76.1-, 2.9-, 71.7- and 51.8-fold for the CD34+/c-kit+ cell culture. The expanded cells could rapidly engraft in the sublethally irradiated mice and reconstitute their hematopoiesis. Co-cultures with MSCs in conjunction with two-step expansion increased expansions of total nucleated cells, GM-CFC and HPP-CFC, which led us to conclude MSCs may create favorable environment for expansions of hematopoietic stem/progenitor cells. The availability of increased numbers of expanded cells by the co-culture with MSCs may result in more rapid engraftment of neutrophils following infusion to transplant recipients. Project supported by NIH-Blood, Heart & Lung (National Institute of Health, USA, IR 01 4L70593-01) and Zhejiang Provincial Science Foundation (No. 011103397), China  相似文献   

9.
  相似文献   

10.
This paper aims to screen and identify sphere clone cells with characteristics similar to cancer stem cells in human gallbladder cancer cell line GBC-SD. GBC-SD cells were cultured in a serum-free culture medium with different concentrations of the chemotherapeutic drug cisplatin for generating sphere clones. The mRNA expressions of stem cell-related genes CD133, OCT-4, Nanog, and drug resistance genes ABCG2 and MDR-1 in sphere clones were detected by quantitative real-time polymerase chain reaction (PCR). Stem cell markers were also analyzed by flow cytometry and immunofluorescent staining. Different amounts of sphere clones were injected into nude mice to test their abilities to form tumors. Sphere clones were formed in serum-free culture medium containing cisplatin (30 μmol/L). Flow cytometry results demonstrated that the sphere clones expressed high levels of stem cell markers CD133+ (97.6%) and CD44+ (77.9%) and low levels of CD24+ (2.3%). These clones also overexpressed the drug resistance genes ABCG2 and MDR-1. Quantitative real-time PCR showed that sphere clones expressed stem cell genes Nanog and OCT-4 284 and 266 times, respectively, more than those in the original GBC-SD cells. Immunofluorescent staining showed that sphere clones overexpressed OCT-4, Nanog, and SOX-2, and low expressed MUC1 and vimentin. Tumor formation experiments showed that 1×103 sphere clone cells could induce much larger tumors in nude mice than 1×105 GBC-SD cells. In conclusion, sphere clones of gallbladder cancer with stem cell-like characteristics can be obtained using suspension cultures of GBC-SD cells in serum-free culture medium containing cisplatin.  相似文献   

11.
Liver fibrosis is the end-stage of many chronic liver diseases and is a significant health threat. The only effective therapy is liver transplantation, which still has many problems, including the lack of donor sources, immunological rejection, and high surgery costs, among others. However, the use of cell therapy is becoming more prevalent, and mesenchymal stem cells (MSCs) seem to be a promising cell type for the treatment of liver fibrosis. MSCs have multiple differentiation abilities, allowing them to migrate directly into injured tissue and differentiate into hepatocyte-like cells. Additionally, MSCs can release various growth factors and cytokines to increase hepatocyte regeneration, regress liver fibrosis, and regulate inflammation and immune responses. In this review, we summarize the current uses of MSC therapies for liver fibrosis and suggest potential future applications.  相似文献   

12.
端粒是真核细胞染色体末端的特殊结构,主要功能是保护染色体不被核酸降解,防止染色体末端的丢失和融合,维持基因的稳定.端粒酶则是能合成端粒DNA的酶,使得端粒的长度和结构得以保持.端粒和端粒酶的发现激起了生命科学对衰老、肿瘤、干细胞等的研究热潮.从端粒和端粒酶与运动员科学选材、运动组织损伤的修复、对成体干细胞的修饰与应用、保护提高线粒体功能、调节胞浆Ca2＋和细胞因子、参与细胞周期调控等诸方面进行综述,旨在为端粒和端粒酶这一最新成果引进运动科学研究提供参考依据.  相似文献   

13.
The in vitro isolation and analysis of pancreatic stem/progenitor cells are necessary for understanding their properties and function; however, the preparation of high-quality single-cell suspensions from adult pancreas is prerequisite. In this study, we applied a cold trypsin-ethylenediaminetetraacetic acid (EDTA) digestion method to disassociate adult mouse pancreata into single cells. The yield of single cells and the viability of the harvested cells were much higher than those obtained via the two commonly used warm digestion methods. Flow cytometric analysis showed that the ratio of ductal or BCRP1-positive cells in cell suspensions prepared through cold digestion was consistent with that found in vivo. Cell culture tests showed that pancreatic epithelial cells prepared by cold digestion maintained proliferative capacity comparable to those derived from warm collagenase digestion. These results indicate that cold trypsin-EDTA digestion can effectively disassociate an adult mouse pancreas into viable single cells with minimal cell loss, and can be used for the isolation and analysis of pancreatic stem/progenitor cells.  相似文献   

14.
  相似文献   

15.
目的从昆明鼠睾丸中克隆Bmi1基因,构建真核表达载体,并转染支持细胞,以便用作培养精原干细胞（SSCs）的滋养层.方法以5日龄昆明鼠为材料,提取小鼠睾丸组织中总RNA后,以RT-PCR技术克隆小鼠睾丸Bmi1基因,构建真核表达载体,并转染TM4细胞（睾丸支持细胞株）,在转染后40 h进行免疫荧光鉴定.结果成功克隆小鼠睾丸Bmi1基因的cDNA,测序正确;免疫荧光细胞染色显示,转染后的支持细胞中有Bmi1蛋白表达.结论本研究为以转染了Bmi1基因的支持细胞作饲养层培养SSCs奠定了基础.  相似文献   

16.
It is generally agreed that adipocytes originate from mesenchymal stem cells in what can be divided into two processes: determination and differentiation. In the past decade, many factors associated with epigenetic signals have been proved to be pivotal for the appropriate timing of adipogenesis progression. A large number of coregulators at critical gene promoters set up specific patterns of DNA methylation, histone acetylation and methylation, and nucleosome rearrangement, that act as an epigenetic code to modulate the correct progress of adipocyte differentiation and adipogenesis during adipogenesis. In this review, we focus on the functions and roles of epigenetic processes in preadipocyte differentiation and adipogenesis.  相似文献   

17.
细胞凋亡是细胞接受某种信号或受到某种因素刺激后,为了维持内环境稳定而发生的一种主动性消亡过程,但是过度的细胞凋亡与多种疾病有关。运动性骨骼肌微损伤是运动过程中肌肉受到牵拉及肌组织内生理生化环境改变而造成的骨骼肌细胞超微结构的损伤。很多实验表明运动训练开始后骨骼肌内的生理生化环境都会导致骨骼肌细胞凋亡,而且细胞凋亡与运动性骨骼肌微损伤具有相同的时相性,显示凋亡可能是运动性骨骼肌微损伤的一个重要因素,从而探讨运动性骨骼肌微损伤的机制。  相似文献   

18.
目的：从新生SD大鼠脑室下区分离并培养神经干细胞．观察其生长、增殖及分化．方法：采取无血清培养和单细胞克隆技术．采用原代贴壁及传代悬浮方法．培养获得细胞克隆．利用免疫细胞化学方法鉴定神经干细胞．结果：从新生SD大鼠脑室下区分离的组织，经原代和传代培养均可形成细胞克隆．且具有增殖能力．原代和传代细胞巢蛋白(Nestin)、神经元特异性烯醇化酶(Neuron specific enolase．NSE)抗原呈阳性．神经干细胞可分化为神经元．结论：用上述方法分离的细胞具有自我更新能力和分化潜能以及很强的增殖能力．属于中枢神经系统的干细胞．  相似文献   

19.
  相似文献   

20.
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号