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21.
目的探讨体外培养大鼠外周血内皮前体细胞(EPCs)与自体骨髓基质细胞(BMSCs)共培养时对BMSCs成骨作用的影响。方法采用密度梯度离心法分离、培养大鼠BMSCs和EPCs,培养细胞分为四组:A组(BMSCs组)、B组(EPCs组)、C组(BMSCs成骨诱导组)及D组(BMSCs和EPCs联合培养组)。通过观察细胞克隆形态、免疫细胞化学、细胞增殖、碱性磷酸酶活性,从酶学、组织学及生化等不同方面观察EPCs对BMSCs成骨活性及生长情况的影响。结果免疫细胞化学染色证实C组培养的细胞具有晚期EPCs的特性。倒置相差显微镜、HE染色均证实共培养的BMSCs和EPCs生长良好,并能够形成与单纯成骨诱导培养的BMSCs相似的钙结节。MTr检测结果:各组细胞增殖差异无统计学意义(P〉0.05)。碱性磷酸酶活性检测结果:C、D组显著高于A、B组(P〈0.05)。结论EPCs和BMSCs联合培养具有良好的细胞相容性,EPCs能够增强成骨细胞的ALP活性,提高成骨细胞的增殖能力。  相似文献   
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人早期胚胎共培养是模拟早期胚胎在体内的发育环境,将体细胞作为营养细胞与胚胎共同培养,一般利用人的输卵管上皮细胞、子宫内膜细胞、卵丘细胞等作为营养细胞;共培养体系通过分泌一些对早期胚胎发育有利的物质和代谢降解胚胎发育过程中产生的有毒物质等,在体外为胚胎发育提供一种更类似于体内的环境,能在一定程度上克服胚胎体外发育阻滞,促进早期胚胎发育,提高胚胎质量,增加胚胎种植率和妊娠率,降低流产率。但共培养涉及到大量的干扰因素,致使对培养液的营养成分和胚胎代谢的研究非常困难。进一步深入研究体细胞共培养对早期胚胎体外发育的影响及其作用机制将为改善体外培养环境和研制复杂培养液提供模型。  相似文献   
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Glutamate toxicity was compared in substantia nigra (SN)/striatum (STR) and SN/cerebellum (CRB) co-cultures on both the entire neuronal population (neuron specific enolase (NSE) immunopositive cells) and dopaminergic neurons (tyrosine hydroxylase (TH) immunopositive cells). In SN/CRB co-cultures NSE- and TH-positive cells were more sensitive to glutamate-induced toxicity than in SN/STR co-cultures. Moreover, in SN/STR co-cultures as compared to SN/CRB and SN cultures, glutamate toxicity was prevented to a larger extent by TCP, a non-competitive NMDA antagonist. These results suggest that target cells induce a differential expression of the different glutamate receptor subtypes in mesencephalic dopaminergic cells. Alternatively, the presence of target cells may induce the selective development of a subpopulation of dopaminergic neurons expressing predominantly NMDA receptors.  相似文献   
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Previously, we had addressed the issues of shape control/maintenance of in vitro engineered human-ear-shaped cartilage. Thus, lack of applicable cell source had become a major concern that blocks clinical translation of this technology. Autologous microtia chondrocytes (MCs) and bone marrow stromal cells (BMSCs) were both promising chondrogenic cells that did not involve obvious donor site morbidity. However, limited cell availability of MCs and ectopic ossification of chondrogenically induced BMSCs in subcutaneous environment greatly restricted their applications in external ear reconstruction. The current study demonstrated that MCs possessed strong proliferation ability but accompanied with rapid loss of chondrogenic ability during passage, indicating a poor feasibility to engineer the entire ear using expanded MCs. Fortunately, the co-transplantation results of MCs and BMSCs (25% MCs and 75% BMSCs) demonstrated a strong chondroinductive ability of MCs to promote stable ectopic chondrogenesis of BMSCs in subcutaneous environment. Moreover, cell labeling demonstrated that BMSCs could transform into chondrocyte-like cells under the chondrogenic niche provided by co-cultured MCs. Most importantly, a human-ear-shaped cartilaginous tissue with delicate structure and proper elasticity was successfully constructed by seeding the mixed cells (MCs and BMSCs) into the pre-shaped biodegradable ear-scaffold followed by 12 weeks of subcutaneous implantation in nude mouse. These results may provide a promising strategy to construct stable ectopic cartilage with MCs and stem cells (BMSCs) for autologous external ear reconstruction.  相似文献   
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目的 探讨体外联合HaCaT细胞共同培养诱导骨髓间充质干细胞(MSCs)向表皮细胞分化的可行性.方法 用聚碳酸酯细胞插入板分层后联合共同培养HaCaT细胞与MSCs,观察培养3、6、9d后的细胞形态,进行角蛋白(CK-19、CK-10)、整合素(α6、β1)染色并用流式细胞仪统计细胞阳性率.结果 共同培养后细胞形态变化明显,共培养3、6d后表皮细胞标志物CK-19、α6整合素、β1整合素免疫荧光染色阳性,细胞阳性率分别为9.3%、8.2%、11.5%和21.7%、34.1%、39.6%,CK10表达呈阴性;共培养9d后CK-19、α6整合素、β1整合素、表达较前减少,阳性率为12.2%、18.6%、16.3%,CK1O出现阳性表达,细胞阳性率为10.7%.结论 分层联合HaCaT细胞共同培养可以诱导骨髓干细胞向表皮细胞进行分化.  相似文献   
29.
目的 探讨软骨共培养体系诱导小鼠ES细胞向软骨细胞分化的可行性.方法 GFP标记的小鼠ES细胞初步分化为EB后,将EB消化为单个细胞,同猪关节软骨细胞按一定比例(1∶3)昆合后接种于PGA材料,体外培养1周后植入裸鼠皮下3周取材.对照组为EB细胞接种组及软骨细胞接种组.取材后行连续冰冻切片,切片分别做荧光拍照,HE染色及甲苯胺蓝染色.结果 组织学结果显示,EB细胞接种组形成畸胎瘤;软骨细胞对照组形成软骨组织;实验组形成软骨组织和畸胎瘤的混合体.甲苯胺蓝染色结果和荧光照片对照结果显示,部分软骨组织GFP阳性,由小鼠ES细胞分化而来.结论 软骨共培养体系可以诱导小鼠ES细胞向软骨细胞分化,但得到的软骨组织不纯,混有畸胎瘤组织.  相似文献   
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It was recently shown that exposure to ZnO nanoparticles (NPs) could induce endoplasmic reticulum (ER) stress both in vivo and in vitro, but the role of ER stress in ZnO NP induced toxicity remains unclear. Because macrophages are sensitive to ER stress, we hypothesized that stressing macrophages with ER stress inducer could enhance the toxicity of ZnO NPs. In this study, the effects of ER stress inducer thapsigargin (TG) on the toxicity of ZnO NPs to THP-1 macrophages were investigated. The results showed that TG enhanced ZnO NP induced cytotoxicity as revealed by water soluble tetrazolium-1 (WST-1) and neutral red uptake assays, but not lactate dehydrogenase (LDH) assay. ZnO NPs dose-dependently enhanced the accumulation of intracellular Zn ions without the induction of reactive oxygen species (ROS), and the presence of TG did not significantly affect these effects. In the co-culture, exposure of THP-1 macrophages in the upper chamber to ZnO NPs and TG significantly reduced the viability of human umbilical vein endothelial cells (HUVECs) in the lower chamber, but the release of tumor necrosis factor α (TNFα) was not induced. In summary, our data showed that stressing THP-1 macrophages with TG enhanced the cytotoxicity of ZnO NPs to macrophages and macrophage-endothelial co-cultures.  相似文献   
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