利用共培养法诱导人胎盘间充质干细胞向成骨细胞分化

目的观察体外人足月胎盘间充质干细胞(h PMSCs)和成骨细胞共培养体系条件下成骨细胞对h PMSCs分化的影响。方法采用胶原酶消化法从人足月胎盘中分离纯化间充质干细胞(MSCs),检测细胞表面标志物、生长曲线、细胞超微结构及成骨能力并对h PMSCs进行鉴定。共培养组将成骨细胞接种于Transwell双层培养皿底层,h PMSCs接种于上层;对照组上层与底层均接种h PMSCs。对诱导后细胞进行碱性磷酸酶染色鉴定。结果胎盘分离细胞经形态、生长速度、细胞表面标志物(CD44和CD29阳性表达为99%,CD34和CD106为1%),确定为胎盘间充质干细胞;头盖骨分离细胞经碱性磷酸酶染色确定为成骨细胞。采用Transwell共培养h PMSCs和成骨细胞组碱性磷酸酶活性染色阳性率为(21.7±5.3)%,表现成骨细胞特性,对照组染色呈阴性。结论人足月胎盘含MSCs,与其他来源MSCs生物学特性相似,成骨细胞生长过程提供的微环境对h PMSCs分化为成骨细胞具有诱导促进作用。     

17β-雌二醇在大鼠骨髓间充质干细胞向成骨细胞转换中的作用

目的探讨17β-雌二醇对大鼠骨髓间充质干细胞(BMSCs)的作用。方法体外分离培养SD大鼠MSCs,诱导大鼠MSCs向成骨细胞定向分化,应用放免法、酶联免疫吸附法观察应用17β-E2对成年大鼠来源的MSCs成骨分化的影响。结果分离得出BMSCs细胞为长梭形或纺锤形,诱导7 d时,大部分细胞逐渐变为多边形,可见碱性磷酸酶(ALP)染色呈阳性;诱导约14 d,细胞互相聚集周围有钙盐晶体形成;诱导培养21 d,细胞聚集形成典型的骨小结,茜素红染色将骨结节中沉积的钙盐染成红色。结论密度梯度离心与贴壁筛选法相结合,是体外分离、纯化MSCs的理想方法;雌激素能通过增强MSCs的成骨分化能力来发挥促骨形成作用。     

鼠成骨细胞诱导兔BMSCs成骨的实验观察

目的观察乳鼠成骨细胞诱导乳兔骨髓间充质干细胞（BMSCs）的成骨情况。方法取SD大鼠乳鼠颅盖骨,采用组织块培养法培养成骨细胞;取乳兔长骨,采用全骨髓培养法培养BMSCs;用Transwell双层细胞培养板共育,实验组于培养上室接种成骨细胞,对照组培养上室不接种细胞,两组培养下室均接种BMSCs。观察BMSCs形态变化,用酶标仪检测诱导分化后BMSCs的ALP活性,RT—PCR检测BMSCs中的骨钙素、骨形态发生蛋白-2（BMP-2）、Ⅰ型胶原基因。结果共培养后实验组BMSCs形态逐渐向成骨样细胞转化,对照组无明显变化;实验组BMSCs中ALP活性高于对照组,实验组的BMSCs的骨钙素、BMP-2、Ⅰ型胶原基因有所表达,对照组无表达。结论乳鼠成骨能够诱导乳兔BMSCs向成骨细胞分化。     

大鼠脑组织匀浆对其BMSCs向神经元样细胞分化的影响

目的:探讨大鼠脑组织匀浆上清对大鼠骨髓间充质干细胞(BMSCs)向神经元样细胞分化的影响.方法:全骨髓培养法从wistar大鼠中分离培养BMSCs,流式细胞仪鉴定,预诱导24h后,分为4组.空白对照组(A组)、碱性成纤维细胞生长因子(bFGF)20ng/mL组(B组)、bFGF20ng/mL+正常脑匀浆上清100μg/mL组(C组)、bFGF 20ng/mL+损伤脑匀浆上清100μL/mL组(D组),诱导48h至细胞分化.免疫细胞化学染色分别检测各组诱导分化后神经特异性烯醇化酶(NSE)、微管相关蛋白-2(MAP-2)和胶质纤维酸性蛋白(GFAP)的表达.结果:第4代BMSCs CD29、CD44和CD34的表达率为99.8%、99.7%和2.2%,诱导后的细胞均具有神经细胞形态特征.免疫组化染色结果:NSE在诱导各组(B组、C组、D组)的表达率为44.50%,63.10%和73.30%,MAP-2的表达率为45.70%、65.30%和75.60%,各组均不表达GFAP.结论:大鼠脑组织匀浆上清能提高BMSCs向神经细胞方向分化的阳性率,损伤脑匀浆的作用更强.     

阿霉素体外抑制成骨分化和促进破骨形成的机制研究

目的:研究阿霉素在体外对大鼠骨髓间充质干细胞(BMSCs)向成骨细胞分化和骨髓单核细胞(BMMs)向破骨细胞分化的影响。方法:将大鼠BMSCs在成骨培养基中用不同浓度的阿霉素处理,以CCK-8法检测其对BMSCs活性的影响,通过碱性磷酸酶(ALP)染色、茜素红染色以及ALP活性的测定检测阿霉素对成骨细胞分化的影响。实时...     

尿酸下调人骨髓间充质干细胞体外诱导为成骨细胞过程中11β-HSD1的表达

目的探讨体外诱导人骨髓间充质干细胞(hBMSCs)向成骨细胞分化过程中,尿酸对其成骨能力以及对11β-羟化类固醇脱氢酶1(11β-HSD1)表达及功能的影响。方法全骨髓体外分离培养健康成年人骨髓间充质干细胞,用细胞形态学及细胞表面标志物对其进行鉴定,培养hBMSCs至第3代后分别以完全培养基(含体积分数10%FBS、1%双抗、89%低糖DMEM)为空白对照组、以成骨培养基(含10-8mol/L地塞米松、50mg/L维生素C、10-2mol/Lβ-甘油磷酸钠的完全培养基)和尿酸干预成骨培养基(分别含0.2、0.4、0.8mmol/L尿酸的成骨培养基)为条件对照组进行培养和诱导。培养诱导14d后,倒置显微镜下观察细胞形态,用碱性磷酸酶染色和茜素红染色进行成骨细胞鉴定,用11β-HSD1免疫细胞化学染色、RT-PCR技术检测各组11β-HSD1 mRNA的表达。结果分离培养的细胞表面标志物CD44表达阳性,CD34表达阴性。成骨培养基和各尿酸干预成骨培养基诱导的细胞碱性磷酸酶染色和茜素红染色均为阳性,钙结节数量随尿酸浓度增高逐渐增多(P0.05)。免疫细胞化学染色结果显示各组细胞胞质均可见棕黄色阳性染色颗粒.病理图象分析软件测定11β-HSD1含量结果显示随尿酸浓度增高,成骨能力增加,光密度值逐渐减少(P0.05)。RT-PCR结果显示各组细胞均有11β-HSD1 mRNA表达,随尿酸浓度增高和成骨能力的增加,11β-HSD1 mRNA表达逐渐减少(P0.05)。结论尿酸能促进hBMSCs向成骨细胞增生和分化,具有浓度依赖性和时间依赖性,尿酸通过下调11β-HSD1 mRNA的表达促进hBMSCs向成骨细胞分化。     

丹参酮ⅡA对大鼠骨髓间充质干细胞成骨分化的影响

目的研究丹参酮ⅡA（TanⅡA）对体外培养的SD大鼠骨髓间充质干细胞（BMSCs）成骨分化能力的影响。方法扩增传代至第3代的SD大鼠BMSCs向成骨诱导分化培养,分为实验组和对照组,采用MTT比色法检测细胞的增殖能力;采用RT—PCR方法检测成骨相关细胞因子mRNA的表达;通过钙结节染色对比观察细胞形态情况。结果实验组各浓度TanⅡA较对照组BMSCs增殖速度提高（P〈0．05）,细胞增殖速率随TanⅡA浓度的增高而加快（P〈0．05）;实验组各浓度TanⅡA成骨相关细胞因子mRNA的表达较对照组提高（P〈0．05）;钙结节染色观察TanⅡA各浓度组均阳性显色,对照组显色不明显。结论TanⅡA能够提高体外培养的BMSCs增殖速率,对BMSCs向成骨细胞分化有明确的诱导作用,缩短骨细胞的成熟时间。     

骨碎补总黄酮对大鼠骨髓间充质干细胞成骨分化过程中TGF-β1、BMP-2分泌的影响

将大鼠分为空白对照组、经典组和骨碎补组,采用全骨髓贴壁法分离纯化大鼠骨髓间充质干细胞(BMSCs),检测BMSCs成骨分化过程碱性磷酸酶活性、矿化结节、转化生长因子-β1(TGF-β1)和骨形态发生蛋白2(BMP-2)的分泌.结果显示,骨碎补总黄酮促进成骨分化同时增加TGF-β1、BMP-2分泌(均P＜0.05).骨碎补总黄酮可能通过上调二者的表达促进成骨,对骨质疏松症可能有积极的治疗意义.     

铁离子对人成骨细胞(hFOB1.19)生物活性影响

目的探讨铁离子对成骨细胞株(hFOB1.19)生物活性,包括碱性磷酸酶活性(alkaline phosphatase activity,APA)、细胞凋亡、钙结节、Ⅰ型胶原(type 1 collagen,COL 1)和骨钙素(osteocalcin,OC)的影响。方法成骨细胞(hFOB1.19)于5%CO234℃培养箱内培养,将不同浓度枸橼酸铁铵(ferric ammonium citrate,FAC)50、100、200μmol/L和去铁胺(deferoxamine,DFO)5、10、20μmol/L分别加入细胞培养基中,MTT法检测成骨细胞增生活性;碱性磷酸酶活性试剂盒检测碱性磷酸酶活性;流式细胞仪检测细胞凋亡;Von kossa染色法行钙结节染色;RT-PCR和Western blotting法分别检测COL1和骨钙素(bone gla protein,BGP)的基因及蛋白表达。结果 (1)48 h后增生活性:FAC组细胞增生活性随FAC干预浓度的增加呈剂量依赖性降低(P0.05),DFO组在5μmol/L浓度组时促进成骨细胞增生,在10、20μmol/L浓度组时抑制成骨细胞增生。(2)10 d时碱性磷酸酶活性:FAC组碱性磷酸酶活性随FAC干预浓度的增加而降低,DFO组碱性磷酸酶活性随DFO干预浓度的增加而升高(P0.05);(3)48 h时凋亡:FAC组细胞凋亡率呈剂量依赖性升高(P0.05),DFO组在5、10μmol/L浓度时抑制细胞凋亡(P0.05),在20μmol/L则促进成骨细胞凋亡(P0.05);(4)21 d时钙结节染色:FAC组随铁离子干预浓度增加,成骨细胞矿化面积、钙结节形成数量均减少,DFO组在5、10μmol/L浓度时促进成骨细胞矿化功能,而20μmol/L浓度时对成骨细胞矿化有抑制效应;(5)3 d时基因及蛋白表达:FAC组COL1、BGP基因和蛋白的表达呈剂量依赖性下调(P0.05);DFO组COLⅠ、BGP基因的表达呈剂量依赖性上调(P0.05),DFO在5、10μmol/L浓度时促进COL1、BGP蛋白表达,在20μmol/L浓度时抑制COL1、BGP蛋白表达。结论不同浓度枸橼酸铁铵均抑制成骨细胞功能活性,提示高铁环境不利于成骨细胞的成骨功能。低铁环境对成骨细胞有双重效应,低剂量去铁胺对成骨细胞活性有促进作用,而高剂量去铁胺则对成骨细胞活性有抑制效应。     

丹酚酸B干预内皮祖细胞对骨髓间充质干细胞向心肌分化早期基因表达的影响

目的 探讨中药丹酚酸B预处理的内皮祖细胞(EPCs)对急性心肌梗死(AMI)大鼠移植骨髓间充质干细胞(BMSCs)向心肌分化早期基因表达的影响.方法 密度梯度离心法和贴壁筛选法培养、纯化EPCs与BMSCs;免疫细胞化学法(CD34/CD133/CD44)分别鉴定两种细胞.结扎大鼠左冠状动脉,制作大鼠AMI模型,42只大鼠随机分为假手术组,模型组,BMSCs组,EPCs+BMSCs组,其中治疗组用丹酚酸B最佳药物浓度处理的EPCs与BMSCs混合,在大鼠AMI区周边分五点注射.RT-PCR检测心肌分化早期基因Nkx2.5、GATA-4表达.结果 细胞移植4 w后,EPCs+BMSCs组心肌Nkx2.5、GATA-4表达量分别为2.256±0.524和1.567±0.287,与对照组比较差异显著.结论 丹酚酸B预处理的EPCs联合BMSCs的移植上调了BMSCs向心肌分化过程中Nkx2.5、GATA-4基因的表达,对心肌细胞的数量增加有重要影响,从而有可能改善心功能.     

树突状细胞联合细胞因子诱导的杀伤细胞对胃癌细胞杀伤作用

目的探讨树突状细胞联合细胞因子诱导的杀伤细胞对胃癌细胞的杀伤作用。方法采用胃癌患者自身血液中单个核细胞(peripheral blood mononuclear cells,PBMC),经体外诱导分别扩增出DC和CIK细胞,二者共同培养后,利用MTT法检测DC细胞联合CIK细胞体外杀伤人胃癌细胞株(MNK-45、MNK-28、SG-7901)的活性。结果DC与CIK细胞共培养后得到的细胞群高表达CD3 CD56 ,平均值达到(56.74±7.63)%。通过彼此相互作用诱导出的细胞群体对胃癌细胞株MNK-45、MNK-28、SG-7901有杀伤作用,且杀伤活性随着效靶比的增加而增强。结论DC与CIK细胞共培养后有很强的增殖能力,对胃癌细胞具有杀伤活性,且其杀伤作用与胃癌细胞类型无相关性。     

DC与CIK或LAK联合对结肠癌细胞株SW480杀伤作用的研究

[目的]研究树突状细胞(DC)联合细胞因子诱导或未诱导的杀伤细胞(CIK)或淋巴因子激活的杀伤细胞(LAK)对结肠癌细胞株SW480的杀伤活性.提供DC联合CIK或LAK治疗结肠癌的实验依据.[方法]取人外周血分离出单个核细胞(PBMNC),诱导生成DC、CIK、LAK细胞;流式细胞仪检测DC经SW480肿瘤抗原冲击后的表型变化;以CIK+DC细胞、CIK细胞、LAK+DC细胞及LAK细胞作为效应细胞,SW480为靶细胞,以15∶1、30∶1、45∶1为效靶比,LDH释放法测定细胞杀伤试验活性;ELISA检测杀伤试验中干扰素γ(IFN-γ)、白细胞介素2(IL-2)、IL-12、IL-17的分泌水平.[结果]流式细胞仪检测DC经SW480肿瘤抗原冲击后,其表面分子HLA-DR、CD40、CD80和CD86表达分别平均为90.23％、73.68％、85.96％、57.55％,与未经肿瘤抗原冲击DC比较,DC成熟的表面标志分子表达明显增加(P＜0.01).相同效靶比下,CIK+DC细胞组对SW480的杀伤作用最强,明显高于其他细胞组(P＜0.01);CIK+ DC细胞组在效靶比为45∶1时,杀伤活性最强(P＜0.01);单独CIK细胞组的杀伤活性明显高于LAK+DC细胞组(P＜0.01);LAK+ DC细胞组的杀伤活性明显高于单独LAK细胞组(P＜0.01).效靶比为45∶1时,各杀伤试验细胞组上清液中IFN-γ、IL-2、IL-12、IL-17的分泌量,CIK+DC细胞组的IFN-γ、IL-12的分泌量显著高于其他细胞组(P＜0.05);LAK+DC、单独LAK细胞组IL-2的分泌量明显高于CIK+DC、单独CIK细胞组(P＜0.05);单独CIK细胞组IFN-γ的分泌量明显高于LAK+DC、单独LAK细胞组(P＜0.05).[结论]CIK+DC细胞组对SW480的杀伤活性明显强于单独CIK、LAK+ DC组、单独LAK细胞组.其机制可能是,SW480抗原致敏的DC分泌IFN-γ、IL-12等刺激、诱导CIK细胞的活化和增殖,明显增强CIK细胞杀伤SW480的活性.     

Differentiation of mesodermal cells from pluripotent stem cells

The pluripotency of embryonic stem cells has been well demonstrated by a vast variety of studies showing the induction of differentiation into desired cell types that have the potential to be used not only in basic studies but also in medical applications. The induction of mesodermal cells, especially blood cells, from embryonic stem cells is notable from the point of view of transplantation, and the methods for this induction have improved over the last few years, with more defined culture conditions in place. Concurrently, the generation of induced pluripotent stem cells from somatic cells opens the possibility of autologous transplantation. In fact, there are a growing number of reports demonstrating that several mesodermal cells can be differentiated from induced pluripotent stem cells using the same methods used for embryonic stem cells. This review summarizes recent advances in the differentiation of mesodermal cells from embryonic stem cells and induced pluripotent stem cells.     

Transdifferentiation of glioblastoma cells into vascular endothelial cells

Glioblastoma (GBM) is the most malignant brain tumor and is highly resistant to intensive combination therapies and anti-VEGF therapies. To assess the resistance mechanism to anti-VEGF therapy, we examined the vessels of GBMs in tumors that were induced by the transduction of p53(+/-) heterozygous mice with lentiviral vectors containing oncogenes and the marker GFP in the hippocampus of GFAP-Cre recombinase (Cre) mice. We were surprised to observe GFP(+) vascular endothelial cells (ECs). Transplantation of mouse GBM cells revealed that the tumor-derived endothelial cells (TDECs) originated from tumor-initiating cells and did not result from cell fusion of ECs and tumor cells. An in vitro differentiation assay suggested that hypoxia is an important factor in the differentiation of tumor cells to ECs and is independent of VEGF. TDEC formation was not only resistant to an anti-VEGF receptor inhibitor in mouse GBMs but it led to an increase in their frequency. A xenograft model of human GBM spheres from clinical specimens and direct clinical samples from patients with GBM also showed the presence of TDECs. We suggest that the TDEC is an important player in the resistance to anti-VEGF therapy, and hence a potential target for GBM therapy.     

Development of hematopoietic cells from embryonic stem cells

Embryonic stem cells are pluripotent stem cells that can differentiate into all somatic cell lineages and germ lineage cells in vivo. In vitro differentiation capacity of the cells is rather limited compared with the in vivo pluripotency. However, differentiation into hematopoietic lineages is easily obtained, and it is a powerful tool to investigate hematopoietic development and differentiation. In this article, we describe a differentiation induction method that we established, the OP9 system, a unique method using the macrophage colony-stimulating factor-deficient stromal cell line OP9. The utility of the OP9 system includes hematopoietic development, differentiation, B-cell formation, osteoclast formation, and so on. The usefulness and limits of embryonic stem cell-derived hematopoietic cells in cell therapy are also discussed.     

Plasma cells induce apoptosis of pre-B cells by interacting with bone marrow stromal cells

By using two-color phenotypic analysis with fluorescein isothiocyanate- anti-CD38 and phycoerythrin-anti-CD19 antibodies, we found that pre-B cells (CD38+CD19+) signifcantly decreased depending on the number of plasma cells (CD38++CD19+) in the bone marrow (BM) in the cases with BM plasmacytosis, such as myelomas and even polyclonal gammopathy. To clarify how plasma cells suppress survival of pre-B cells, we examined the effect of plasma cells on the survival of pre-B cells with or without BM-derived stromal cells in vitro. Pre-B cells alone rapidly entered apoptosis, but interleukin-7 (IL-7), a BM stromal cell line (KM- 102), or culture supernatants of KM-102 cells could support pre-B cell survival. On the other hand, inhibitory factors such as transforming growth factor-beta1 (TGF-beta1) and macrophage inflammatory protein- 1beta (MIP-1beta) could suppress survival of pre-B cells even in the presence of IL-7. Plasma cells alone could not suppress survival of pre- B cells in the presence of IL-7, but coculture of plasma cells with KM- 102 cells or primary BM stromal cells induced apoptosis of pre-B cells. Supernatants of coculture with KM-102 and myeloma cell lines (KMS-5) also could suppress survival of pre-B cells. Furthermore, we examined the expression of IL-7, TGF-beta1, and MIP-1beta mRNA in KM-102 cells and primary stromal cells cocultured with myeloma cell lines (KMS-5). In these cells, IL-7 mRNA was downregulated, but the expression of TGF- beta1 and MIP-1beta mRNA was augmented. Therefore, these results suggest that BM-derived stromal cells attached to plasma (myeloma) cells were modulated to secrete lesser levels of supporting factor (IL- 7) and higher levels of inhibitory factors (TGF-beta1 and MIP-1beta) for pre-B cell survival, which could explain why the increased number of plasma (myeloma) cells induced suppression of pre-B cells in the BM. This phenomenon may represent a feedback loop between pre-B cells and plasma cells via BM stromal cells in the BM.     

B-lymphoid cells with attributes of dendritic cells regulate T cells via indoleamine 2,3-dioxygenase

A discrete population of splenocytes with attributes of dendritic cells (DCs) and coexpressing the B-cell marker CD19 is uniquely competent to express the T-cell regulatory enzyme indoleamine 2,3-dioxygenase (IDO) in mice treated with TLR9 ligands (CpGs). Here we show that IDO-competent cells express the B-lineage commitment factor Pax5 and surface immunoglobulins. CD19 ablation abrogated IDO-dependent T-cell suppression by DCs, even though cells with phenotypic attributes matching IDO-competent cells developed normally and expressed IDO in response to interferon γ. Consequently, DCs and regulatory T cells (Tregs) did not acquire T-cell regulatory functions after TLR9 ligation, providing an alternative perspective on the known T-cell regulatory defects of CD19-deficient mice. DCs from B-cell–deficient mice expressed IDO and mediated T-cell suppression after TLR9 ligation, indicating that B-cell attributes were not essential for B-lymphoid IDO-competent cells to regulate T cells. Thus, IDO-competent cells constitute a distinctive B-lymphoid cell type with quintessential T-cell regulatory attributes and phenotypic features of both B cells and DCs.