Biological Characteristics of Human Bone Marrow Mesenchymal Stem Cell Cultured in Vitro

Some biological characteristics of human bone marrow mesenchymal stem cells (MSCs) cultured in vitro were observed, hMSCs were isolated from bone marrow and purified by density gradient eentrifugation method, and then cultured in vitro. The proliferation and growth characteristics of hMSCs were observed in primary and passage culture. MSCs of passage 3 were examined for the purify by positive rate of CD29 and CD44 through flow eytometry. Human bone marrow MSCs showed active proliferation capacity in vitro. The purify of MSCs separated by our method was higher than 90%. It was concluded that hMSCs have been successfully cultured and expanded effectively. It provided a foundation for further investigation and application of MSCs。     

Evaluation of CD24 as a marker to rapidly define the mesenchymal stem cell phenotype and its differentiation in human nucleus pulposus

Background Recent studies have indicated that human nucleus pulposus contain mesenchymal stem cells （NP-MSCs）. However, the immunophenotypic variation of NP-MSCs in vitro was unclear. The present study was conducted to address the immunophenotypic variation of mesenchymal stem cells in nucleus pulposus under continuous proliferation in vitro and show the difference between mesenchymal stem cells and nucleus pulposus cell. Methods Tissue samples were obtained from thoracolumbar burst fracture patients and degenerative disc disease patients who underwent discectomy and fusion procedures. Flow cytometric and laser scanning confocal microscope （LSCM） were used to detect the variation of mesenchymal stem cells in nucleus pulposus which were expressing CD105 and CD24 in condition with or without transforming growth factor [31 （TGF-131）. Results More than 90% of the analyzed primary cells of mesenchymal stem cells in nucleus pulposus fulfilled the general immunophenotyping criteria for MSCs, such as CD44, CD105 and CD29, but the marker of mature NP cells characterized as CD24 was negative. In continuous cultures, the proportion of mesenchymal stem cells which were expressing CD44, CD105 and CD29 in nucleus pulposus gradually decreased. The mesenchymal stem cells in nucleus pulposus cells were positive for CD105 and CD29, with slight positivity for CD44. The CD24 expression gradually increased in proliferation. Bi- parametric flow cytometry and laser scanning confocal microscopy confirmed the presence of cells which were expressing CD105 and CD24 independently, and only a small part of cells expressed both CD105 and CD24 simultaneously. TGF-{31 could stimulate mesenchymal stem cells in nucleus pulposus to express CD24. Conclusions Non-degenerative and degenerative NP contains mesechymal stem cells. The variation of CD24 can be used as a marker to identify the NP-MSCs differentiation into NP-like cells.     

人骨髓间充质干细胞向血管内皮细胞诱导的研究

目的 研究人骨髓间充质干细胞(HBMCs)的体外培养和向血管内皮细胞的诱导分化.方法 利用密度梯度离心法将HBMCs从人骨髓中分离出来,体外扩增.将第三代的细胞以含VEGF,bFGF的培养基定向诱导,使其向内皮细胞方向分化.利用免疫细胞化学和流式细胞学检测诱导后的细胞表型.结果 原代未经诱导的骨髓干细胞,培养3周后细胞形态呈梭形,诱导后第7天的细胞呈椭圆形或不规则形,第14天细胞大致呈铺路石样改变.免疫细胞化学显示CD31、CD34、vWF因子呈阳性,流式细胞仪测定CD31、vWF因子阳性率分别为87.5%、82.6%,双阳性率为71.2%.结论 骨髓间充质干细胞在内皮细胞生长因子和碱性成纤维细胞因子的诱导下向血管内皮细胞方向分化. Abstract： Objective To study the culture methods of human bone marrow mesenchymal stem cells(MSCs) and differentiation into vascular endothelial cells in vitro. Methods Bone marrow mesenchymal stem cells were isolated and cultivated by density gradient centrifugation method. Induce the third generation to vascular endothelial cells with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Immunophenotypes of cells were detected by flow cytometry techniques and immunocyte chemistry after the transfection. Results After three weeks of primary culture of MSCs, the cell showed on fusiform shape. After 7 days induction, the cell showed on ellipse and irregular shape. After two weeks transfection, the cell exhibited a Cobblestone-like morphology. The cell expressed CD34,CD31,vWF after transfection by immunocyte chemistry. The positive rates of CD31 vWF were 87.5% and 82.6%, and the double positive rate was 71.2%. Conclusions Bone marrow mesenchymal stem cells can differentiate into vascular endothelial cells by treating with vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF).     

Human umbilical cord mesenchymal stem cells and the treatment of spinal cord injury

Objective To review the recent studies about human umbilical cord mesenchymal stem cells （hUCMSCs） and advances in the treatment of spinal cord injury. Data sources Published articles （1983-2007） about hUCMSCs and spinal cord injury were selected using Medline. Study selection Articles selected were relevant to development of mesenchymal stem cells （MSCs） for transplantation in spinal cord injury therapy. Of 258 originally identified articles 51 were selected that specifically addressed the stated purpose. Results Recent work has revealed that hUCMSCs share most of the characteristics with MSCs derived from bone marrow and are more appropriate to transplantation for cell based therapies. Conclusions Human umbilical cord could be regarded as a source of MSCs for experimental and clinical needs. In addition, as a peculiar source of stem cells, hUCMSCs may play an important role in the treatment of spinal cord injury. Chin Med J 2009;122（2）：225-231     

Monitoring the source of mesenchymal stem cells in patients after transplantation of mismatched-sex hematopoietic stem cells plus third-party cells

Background In bone marrow transplant patients, the microenvironment in bone marrow is damaged after chemotherapy or radiotherapy. Subsequent to allogenic hematopoietic stem cell transplantation in patients with clinically successful engraftments, the source of mesenchymal stem cells （MSCs） remains controversial. To further verify the stimulatory effect of the simultaneous transplantation of cells from second donors on engraftment success for hematopoietic stem cell transplantation in support of donor MSCs engraftments, the aim of this study is to monitor the dynamics of the engraftment of bone marrow-derived MSCs in patients after transplantation with mismatched-sex hematopoietic stem and third-party cells. Methods In this study, the hematopoietic stem cells from 32 clinical donors of different sexes that resulted in successful engraftments were selected for transplantation and were classified into three groups for research purposes： group A consisted of 14 cases of transplantation with bone marrow and recruited peripheral hematopoietic stem cell transplantation, group B contained 8 cases of simultaneous re-transfusion of MSCs from the second donor, and group C contained 10 cases of simultaneous re-transfusion of umbilical blood from the second donor. The bone marrow from 32 patients with successful engraftments of hematopoietic transplantation were selected and sub-cultured with MSCs. Flow cytometry （FCM） was used to measure the expression of surface antigens on MSCs. Denaturing high-performance liquid chromatography （DHPLC） in combination with polymerase chain reaction amplification of short tandem repeats （STR- PCR） was used to measure the engraftment status of fifth-generation MSCs in patients. Fluorescence in situ hybridization （FISH） revealed the sex origin of the fifth-generation MSCs in 32 patients. Dynamic examinations were performed on patients receiving donor transplantations. Results The progenies of fifth-generation MSCs were successfully cultured in 32 cases. The results of FCM demonstrated that the expression levels of CD14＋ and CD45＋ cells were lower than 0.04% in the fifth-generation MSCs. The analysis using DHPLC and FISH showed similar results. One patient from group B also received a temporary transplantation of MSCs from the donor. The MSCs in the remaining 31 patients all originated from the patients themselves. Conclusions After transplantation, the MSCs present in patients originated from the host. In patients transplanted with MSCs from a second donor, the phenomenon of temporary chimerization of MSCs was observed.     

In Vitro Chondrogenic Phenotype Differentiation of Bone Marrow-derived Mesenchymal Stem Cells

In order to study the chondrogenic phenotype differentiation of adult sheep bone marrowderived mesenchymal stem cells (MSCs) in a defined medium as potential seed cells for cartilage tissue engineering, MSCs were isolated by density centrifugation with Percoll solution from bone marrow aspirated from sheep iliac crest. The third passage of MSCS were induced with H-DMEM containing TGF-β3 .IGF-I, Dexamethasone and VitC. The shape and ultrastructure of cells were observed, toluidine blue stain for GAG and immunohistochemistry for type II collagen were applied for chondrogenic phenotype identification. After 14 days of induction, MSCs changed from a spindlelike appearance to a polynal shape, a large amount of endoplasmic reticulum, Golgi complex and mitochondria were observed, and the differentiation of MSCs chondrogenic phenotype was verified by positive staining of toluidine blue and immunohistochemistry. MSCs derived from bone marrow can differentiate to chondrogenic phenotype when induced in vitro and can be used as optimal seed cells for cartilage tissue engineering.     

Implication of expression of Nanog in prostate cancer cells and their stem cells

Recent studies suggested that the prostate cancer may arise from prostate cancer stem cells that share some same characteristics with normal stem cells. The purpose of this study was to detect the differences of Nanog expression between PC3 prostate cancer cell line and its tumor stem cells, and the relationship was preliminarily examined between Nanog and prostate cancer and its tumor stem cells. By using magnetic active cell sorting (MACS), we isolated a population of CD44+/CD133+ prostate cancer cells that display stem cell characteristics from PC3 cell line. Immu-nohistochemistry revealed positive expressions of CD44, CD133 and α2β1-integin in the isolated cells. CCK-8 analysis showed that isolated cells had a strong proliferative ability. The formation of the cell spheres in serum-free medium and holoclones in serum-supplied medium showed that the cells were capable of self-renewing, indicating that the isolated cells were a population of cancer stem-like cells derived from PC3 cell line. Western blotting exhibited that the isolated cells had higher experession of Nanog, an embryonic stem marker, as compared with PC3 cells. Our study showed that Nanog might be helpful in sustaining the self-renewal and the undifferentiation of prostate cancer stem cells, and may serve as a marker for prostate cancer stem cells for isolation and identification.     

TISSUE-ENGINEERED GRAFT CONSTRUCTED BY SELF-DERIVED BONE MARROW MONONUCLEAR CELLS AND HETEROGENEOUS ACELLULARIZED TISSUE MATRIX

Objective To create a method for constructing a tissue-engineered graft with self-derived bone marrow cells and heterogeneous acellular matrix. Methods The mononuclear cells were isolated from bone marrows drawn from piglets and cultured in different mediums including either vascular endothelial growth factor （VEGF） or platelet derived growth factor BB （PDGF-BB） to observe their expansion and differentiation. The aortas harvested from canines were processed by a multi-step decellularizing technique to erase. The bone marrow mononuclear cells cultured in the mediums without any growth factors were seeded to the acellular matrix. The cells- seeded grafts were incubated in vitro for 6 d and then implanted to the cells-donated piglets to substitute parts of their native pulmonary arteries. Results After 4 d culturing, the cells incubated in the medium including VEGF showed morphological feature of endothelial cells （ECs） and were positive to ECs-specific monoclonal antibodies of CD31, FLK-1, VE-Cadherin and vWF. The cells incubated in the medium including PDGF-BB showed morphological feature of smooth muscle cells （SMCs） and were positive to SMCs-specific monoclonal antibodies of α-SMA and Calponin. One hundred days after implantation of seeded grafts, the inner surfaces of explants were smooth without thrombosis, calcification and aneurysm. Under the microscopy, plenty of growing cells could be seen and elastic and collagen fibers were abundant. Conclusion Mesenchymal stem cells might exist in mononuclear cells isolated from bone marrow. They would differentiate into endothelial cells or smooth muscle cells in proper in vitro or in vivo environments. The bone marrow mononuclear cells might be a choice of seeding cells in constructing tissue-engineered graft.     

人骨髓间充质干细胞分离培养及多向分化的实验研究

目的:探索体外分离子与培养人骨髓间充质干细胞的方法,同时研究其细胞生物学特性,分析其作为骨组织工程种子细胞的可行性。方法:分离人骨髓间充质干细胞(human bone marrow mesenchymal stemcells,hBMSCs),通过常规培养,在体外观察其生长特性、抗原表达等特征;然后通过条件培养基定向诱导,观察其分化潜能。结果:人骨髓间充质干细胞在体外可以大量增殖,常规培养条件下,原代培养需要2～3周,转代后生长速度加快;应用流式细胞仪检测MSCs的表面抗原,CD44、CD29、CD105阳性,CD45、CD06、CD34以及HLA-DR阴性;在相应条件培养基的诱导作用下,MSCs可以分化为成骨细胞、软骨细胞以及神经细胞。结论:人骨髓间充质干细胞可以从骨髓中分离并在体外培养增殖,同时在体外具有多向分化潜能,可以分化成为骨细胞,符合骨组织工程种子细胞的要求。     

成人骨髓间充质干细胞的体外分离培养和生物学特性

目的：建立一种成人骨髓间充质干细胞体外分离、培养和扩增的方法，并探讨其部分生物学活性及向脂肪细胞诱导分化的方法，并以此鉴定所获细胞。方法：采用1．073g／ml的Percoll分离液分离成人骨髓间充质干细胞。接种于纤维连接蛋白包被，含有表皮生长因子和血小板原性生长因子BB的2％胎牛血清培养液中，并利用其贴壁性进行纯化；观察其形态学变化及超微结构，流式细胞仪检测其表面标记物；采用10％胎牛血清和尼克酰胺诱导其向脂肪细胞的分化。结果：原代和传代培养均保持较强的增殖能力，超微结构显示了干细胞的幼稚特性，流式细胞仪检测示CD34、CD45、CD19、组织相容性抗原-DR阴性，CD44、CD10、CD29、CD13阳性。体外能够分化成为脂肪细胞，油红O染色阳性。结论：采用该方法骨髓间充质干细胞生长稳定，扩增较快；一定条件下能够定向分化成为脂肪细胞；我们所获得的细胞具有间充质干细胞的特性。     

兔骨髓间充质干细胞培养与多向分化潜能鉴定的实验研究

目的原代培养兔骨髓间充质干细胞(mesenchymal stem cells,MSCs),观察体外培养中MSCs的生物学特性及多向分化潜能。方法通过密度梯度离心联合贴壁培养法,体外分离、纯化、扩增兔骨髓间充质干细胞,观察形态学特点,测绘传代MSCs生长曲线,检测细胞周期及表面标记,体外诱导MSCs向成骨细胞、成脂肪细胞分化并鉴定。结果原代及传代MSCs为长梭形成纤维细胞样细胞;生长曲线显示传代细胞具有类似的生长规律;流式细胞仪分析MSCs CD44表达阳性,CD45表达阴性;细胞周期分析显示87%以上细胞处于G0/G1期;经成骨细胞诱导,细胞碱性磷酸酶染色阳性;经成脂肪细胞诱导,细胞内出现红染脂滴。结论通过密度梯度离心联合贴壁培养法可大量扩增、纯化MSCs,所获细胞具有高度自我更新和多向分化潜能。     

MSCs 2种分离培养方法及其培养液中的 VEGF、SDF-1α浓度比较

目的：通过2种分离培养方法所得骨髓间充质干细胞（MSCs）的生长特征和微环境中细胞因子的比较,提供一种可以快速、安全、高效地为临床和实验提供大量优质MSCs的方法。方法提取C57BL／c小鼠的骨髓,分别作密度梯度离心法和全骨髓贴壁培养分离法分离培养MSCs ,通过流式细胞仪检测细胞表面CD29＋、CD31－、CD34－、CD45－表达水平,并比较各自所得细胞的生长曲线;ELISA检测培养液中的血管内皮生长因子（VEGF）、SDF‐1α浓度并比较二者的差异。结果与密度梯度离心法比较,全骨髓贴壁分离法所得原代细胞有较快的生长速度,较短的生长周期;培养液中VEGF和SDF‐1α浓度也稍高于密度梯度离心法。结论全骨髓贴壁培养法可以快速、方便、有效地为临床和实验提供大量MSCs ,所得细胞的培养环境优于密度梯度离心法,减少了对细胞功能的损害。     

骨髓间质干细胞体外预构组织工程化肌腱的实验研究

目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱.     

大鼠骨髓间充质干细胞的分离培养及表型和功能特点

目的 建立体外分离纯化、培养扩增大鼠骨髓间充质干细胞(mesenchymal stem cells，MSCs)的方法，探讨其表型和功能特点。方法 用密度梯度离心结合贴壁培养法分离纯化大鼠骨髓MSCs，传代扩增，测定生长曲线，通过形态学观察，细胞化学及免疫细胞化学法分析大鼠骨髓MSCs的表型和功能特点。结果 MSCs属骨髓中单个核细胞，密度梯度离心结合贴壁培养法能有效分离纯化大鼠骨髓MSCs，在含10％小牛血清的L-DMEM中，1、3、5代细胞生长曲线基本相同，增殖快，每传代一次细胞约增加2．2倍。细胞呈均一的成纤维细胞样，表达CD44、CD54、纤维粘连蛋白(fibronectin，FN)、Ⅰ型胶原(collagenⅠ)。加入地塞米松(Dex 10^-8mol／L)、β-甘油磷酸钠(β-GP 10mmol／L)、抗坏血酸(AA50μg／ml)可诱导MSCs分化为成骨细胞，碱性磷酸酶(alkaline phosphatase，ALP)活性增高，形成矿化结节。结论 所分离、培养的细胞具有间充质干细胞的表型和功能特点，建立了体外分离纯化、培养扩增大鼠骨髓MSCs的方法。     

人骨髓间充质干细胞的分离培养、多向分化与鉴定

 目的 探索一个高效分离和扩增人骨髓间充质干细胞的方法，并通过形态学和多向分化能力进行鉴定。方法 抽取人胸椎骨髓标本，联合利用密度梯度离心和差异贴壁法分离MSCs，体外扩增后传代，相差显微镜形态学观察和流式细胞仪检测细胞表面标记CD13、CD29、HLA-2、CD34、CD45和HLA-DR。在地塞米松、左旋VitC、b-磷酸甘油、FK506作用下向成骨细胞诱导分化；在TGF-beta 3、重组人胰岛素、丙酮酸钠、亚硒酸等作用下向软骨细胞诱导分化；在地塞米松、IBMX、吲哚美辛的作用下向脂肪细胞诱导分化；在VEGF、bFGF作用下向血管内皮细胞分化。结果 原代和传代细胞呈梭形外观，生长增殖能力良好。细胞表面标记物CD13、CD29，HLA-2阳性，CD34、CD45 和HLA-DR阴性。经定向诱导分化后，细胞分别呈现成骨细胞、软骨细胞、脂肪细胞和血管内皮细胞的表型特征。结论 该方法能从人骨髓中高效分离和扩增MSCs，能成功定向分化为成骨细胞、软骨细胞、脂肪细胞和血管内皮细胞。     

人骨髓间充质干细胞体外分化为雪旺样细胞的方法

目的 :建立人骨髓间充质干细胞体外向雪旺样细胞定向诱导分化的方法。方法 :取健康人骨髓血标本 ,利用percoll(密度为 1.0 73 g·ml-1)分离骨髓单个核细胞 ,在DMEM LG + 10 % (体积分数 )FBS中培养 ,通过流式细胞术对培养细胞进行表型测定 ,对第 2、3、5、8代间充质干细胞进行定向诱导分化 ,用单抗S 10 0、神经胶质纤维酸性蛋白 (glialfibrillargacidicprotein ,GFAP) ,通过免疫组化方法对诱导的细胞进行鉴定。 结果 :经 percoll分离的间充质干细胞可传 16代 ,细胞数增加了大约 6× 10 7倍。流式细胞术结果显示 :percoll分离出来的未经培养的细胞 ,其CD2 9+CD4 4 +CD3 4 -CD4 5 -细胞数为 3 2 .4 7%± 3 .4 9% ,而培养后贴壁细胞中CD2 9+CD4 4 +CD3 4 -CD4 5 -细胞数为 94 .3 8%± 1.5 0 %。诱导后免疫组化染色结果显示 :由 β ME +bFGF预诱导、β ME +bFGF诱导的S 10 0阳性细胞最多 ,可达 90 %± 4 % ,GFAP阳性细胞为 2 1%± 5 %。结论 :人骨髓中间充质干细胞能定向诱导分化成雪旺样细胞。     

Biological characteristics of human bone marrow mesenchymal stem cell cultured in vitro

Summary Some biological characteristics of human bone marrow mesenchymal stem cells (MSCs) culturedin vitro were observed. hMSCs were isolated from bone marrow and purified by density gradient centrifugation method, and then culturedin vitro. The proliferation and growth characteristics of hMSCs were observed in primary and passage culture. MSCs of passage 3 were examined for the purify by positive rate of CD29 and CD44 through flow cytometry. Human bone marrow MSCs showed active proliferation capacityin vitro. The purify of MSCs separated by our method was higher than 90%. It was concluded that hMSCs have been successfully cultured and expanded effectively. It provided a foundation for further investigation and application of MSCs. FA Xian’en, male, born in 1962, Professor     

人骨髓间充质干细胞体外培养及生物学特性观察

目的：观察体外培养的人骨髓间充质干细胞(MSCs)部分生物学特性。方法：自健康人骨髓中分离出MSCs,进行原代培养,第5d首次更换培养液,以去除未贴壁细胞,以后每周换液2次,细胞铺满整个培养瓶底90％时开始传代培养。倒置相差显微镜下观察原代及传代细胞形态及生长特性,并绘制传代细胞的生长曲线。流式细胞仪检测第3代MSCs细胞表面分子CD29、CD44,以进行MSCs鉴定。结果：MSCs体外培养为贴壁生长。MSCs原代培养约18～21d才达传代要求;传代培养细胞生长潜伏期仅24～36h,对数增长期约3～5d,之后为平台期,4～6d传1代。传至第8代,出现凋亡征象。第3代MSCs细胞表面CD29、CD44的表达率分别为90．6％和91．5％,MSCs均一性较高。结论：从人骨髓中分离出的MSCs在体外环境中具有很强的自我更新和分裂增殖能力。