脑微血管内皮细胞条件培养液对星形胶质细胞活性的影响

目的:观察脑微血管内皮细胞与星形胶质细胞的相互关系,探讨血脑屏障维持脑内环境稳定的生理学基础.方法:原代培养大鼠脑皮质微血管内皮细胞,传至三代,收集在指数生长期细胞生长48 h后的务件培养液;将条件培养液分别按20%、30%、40%、50%、60%、70%、80%、90%、100%不同浓度作用于星形胶质细胞,MTT法检测不同浓度内皮细胞条件培养液作用于星形胶质细胞24 h、48h后的活性变化.结果:48h时间点的各浓度内皮细胞条件液组与相应的正常对照组相比差异均有显著统计学意义(P<0.01),内皮细胞条件液对星形胶质细胞表现出显著的抑制效应,而24 h的70%、80%、90%、100%浓度组与相应正常对照组相比也有显著统计学意叉的差异(P<0.01),且有浓度依赖性.结论:正常脑微血管内皮细胞条件培养液抑制了正常星形胶质细胞的活性.     

通络救脑注射液对脑微血管内皮细胞活性影响的特征

目的：观察通络救脑注射液对培养的正常及缺血脑微血管内皮细胞的活性影响。揭示其通络作用的效应靶点与特征。方法：原代培养大鼠脑皮质微血管内皮细胞,传至第三代。分为正常及拟缺血组,采用培养基氧糖刺夺（OGD）法建立拟缺血模型。通过四甲基偶氮唑盐（MTT）比色分析法测定不同浓度的通络救脑注射液对正常及OGD内皮细胞的活性影响。结果：通络救脑注射液作用于正常脑微血管内皮细胞,与未加药组比较,小剂量药物抑制细胞活性趋势,大剂量促进细胞活性趋势,剂量总趋势呈反抛物线形;通络救脑注射液作用于OGD组脑微血管内皮细胞,小剂量范围促进内皮细胞的增殖活性,呈显著和极显著差异,而大剂量组则抑制细胞活性,剂量总趋势呈抛物线形。结论：通络救脑注射液对正常及缺血脑微血管内皮细胞具有双向调节作用,药物剂量与细胞增殖活性呈非线性关系。天剂量与小剂量可能是不同的作用机制,反映了中药复方药效的多维性。     

脑微血管内皮细胞条件培养液对星形胶质细胞的影响及通络中药的干预特征

目的:揭示脑微血管内皮细胞生理、病理及通络中药处理后不同状态的培养液对正常星形胶质细胞影响的特征,从细胞间相互作用角度探讨脑微血管内皮细胞与星形胶质细胞的生物学关系,为阐释脑微环境稳定的血脑屏障维护机制以及通络中药通过内皮细胞调节脑内微环境理论假说提供新的证据。方法:制备正常、拟缺血和拟缺血合并通络救脑注射液处理的大鼠脑微血管内皮细胞条件培养液,观察其对星形胶质细胞活性和凋亡率的影响。结果:与正常星形胶质细胞相比,正常内皮细胞条件培养液能够降低正常星形胶质细胞的活性,并促进星形胶质细胞的凋亡;而拟缺血处理的内皮细胞条件培养液能够提高正常星形胶质细胞的活性和凋亡率;拟缺血合并通络药物处理的内皮细胞条件培养液对正常星形胶质细胞的活性有提高作用,并显著降低其凋亡率。结论:三种不同处理方式的内皮细胞条件培养液对正常星形胶质细胞活性和凋亡产生不同的影响,提示不同状态的微血管内皮细胞对脑内微环境产生影响,通络救脑注射液可能通过调节微血管内皮细胞的分泌而对星形胶质细胞发挥作用。     

川芎嗪对PC12细胞氧糖剥夺后细胞内抗超氧阴离子能力和过氧化氢的影响

目的:探讨川芎嗪(Tetramethylpyrazine,TMP)对PC12细胞氧糖剥夺/复氧复糖损伤后细胞内抗超氧阴离子能力和过氧化氢(H2O2)的影响.方法:建立PC12细胞氧糖剥夺(Oxygen-Glucose Deprivation,OGD)模型,复氧复糖给予不同浓度(0.01、0.02、0.04、0.08、0.16、0.32、0.64、1.28、2.56、5.12、10.24 μmol/L)的川芎嗪,培养24 h后行MTT和LDH的检测.采用四甲基偶氮唑(Methyl Thiazolyl Tetrazolium,MTT)比色检测细胞生存率,并检测细胞内抗超氧阴离子能力和过氧化氢.结果:氧糖剥夺可明显降低PC12细胞活性(55.05％),而川芎嗪可以显著提高PC12细胞活性,其作用呈现一定的剂量—效应相关性.复氧复糖后给予0.16 μmol/L川芎嗪可以提高PC12细胞的活性到75.38％.氧糖剥夺/复氧复糖后6h、24h,TMP组(川芎嗪组)抗超氧阴离子能力明显高于OGD组(模型组)(P＜0.05),而H2O2的含量TMP组明显低于OGD组(P＜0.05).结论:川芎嗪可能提高抗超氧阴离子能力,减少H2O2的产生,从而减轻PC12细胞氧糖剥夺/复氧复糖损伤,具有较好的治疗作用.     

通络救脑注射液对大鼠脑微血管内皮细胞活性 及其条件培养液影响的初步研究

目的：观察通络救脑注射液对正常及拟缺血大鼠脑微血管内皮细胞的活性影响,并初步探讨细胞条件培养液内蛋白分泌的时效特征、奠定可溶性蛋白深入分析的技术基础。方法：通络救脑注射液作用于正常夏拟缺血脑微血管内皮细胞之后,用MTS／PMS比色分析法测定细胞的活性,Bradford法测定细胞培养液总蛋白含量,比色分析法测定细胞培养液乳酸脱氢酶（LDH）漏出值,同步观察了5个时间点的细胞活性及条件培养液总蛋白量及LDH释放量。结果：通络救脑注射液能够提高拟缺血细胞的活性,且抑制LDH释放量;正常组分泌总蛋白量3h达到高峰,此时细胞活性最佳,LDH释放量亦少。拟缺血组分泌总蛋白量是6h达到高峰,此时LDH释放量最少,但细胞活性与3h比较有所下降。结论：通络救脑注射液对拟缺血细胞损伤具有保护作用：以3h至6h的细胞条件培养液做为收集目标是研究条件培养液的最佳时间段。     

氨磷汀对氧糖剥夺引起的PC12 细胞缺血再灌注损伤的保护作用研究

目的:研究氨磷汀对体外培养的神经元样细胞的缺血再灌注损伤的保护作用,为其最终用于临床脑缺血的治疗打下基础。方法:体外培养的PC12细胞氧糖剥夺4h后复氧复糖,给予不同浓度的氨磷汀处理,20h后镜下观察细胞形态学变化,用MTT和LDH检测细胞活力和损伤情况,免疫荧光染色观察凋亡细胞,流式细胞仪计数凋亡细胞的比例。结果:高浓度氨磷汀对正常PC12细胞活力有抑制作用(P<0.05),而低浓度则无。氨磷汀可以提高缺血再灌注损伤PC12细胞活力(P<0.05),减少LDH释放(P<0.05),保护细胞正常形态,抑制细胞凋亡(P<0.05)。结论:氨磷汀对氧糖剥夺引起的神经元样细胞的缺血再灌注损伤具有保护作用。     

氨磷汀对氧糖剥夺引起的PC12细胞缺血再灌注损伤的保护作用研究

目的：研究氨磷汀对体外培养的神经元样细胞的缺血再灌注损伤的保护作用,为其最终用于临床脑缺血的治疗打下基础。方法：体外培养的PC12细胞氧糖剥夺4h后复氧复糖,给予不同浓度的氨磷汀处理,20h后镜下观察细胞形态学变化,用MTT和LDH检测细胞活力和损伤情况,免疫荧光染色观察凋亡细胞,流式细胞仪计数凋亡细胞的比例。结果：高浓度氨磷汀对正常PC12细胞活力有抑制作用（P〈0.05）,而低浓度则无。氨磷汀可以提高缺血再灌注损伤PC12细胞活力（P〈0.05）,减少LDH释放（P〈0.05）,保护细胞正常形态,抑制细胞凋亡（P〈0.05）。结论：氨磷汀对氧糖剥夺引起的神经元样细胞的缺血再灌注损伤具有保护作用。     

Stathmin 在微血管内皮细胞的表达与胶质瘤恶性程度关系

目的:检测Stathmin在正常脑组织及不同级别胶质瘤微血管内皮细胞中的表达情况。方法:利用结合CD105单克隆抗体的免疫磁珠内皮细胞分选系统特异性分选出68例胶质瘤微血管内皮细胞(其中低级别胶质瘤(WHO分级Ⅰ-Ⅱ)24例,高级别胶质瘤(WHO分级Ⅲ-Ⅳ)44例)和20例正常脑组织微血管内皮细胞。应用免疫组化、RT-PCR和Western blot检测Stathmin在胶质瘤微血管内皮细胞和正常脑组织微血管内皮细胞中的表达。结果:免疫组化证实Stathmin在正常脑组织微血管内皮细胞、低级别胶质瘤微血管内皮细胞和高级别胶质瘤微血管内皮细胞的表达百分率分别是20%,66%和95%(P<0.05)。RT-PCR和Western blot法检测显示,Stathmin在胶质瘤微血管内皮细胞中的表达明显增高。低级别胶质瘤组、高级别胶质瘤组分别与正常组比较,均有显著性差异(P<0.01);且低级别胶质瘤组与高级别胶质瘤组比较,有显著性差异(P<0.01),随着胶质瘤恶性程度的增加,Stathmin表达上调,具有统计学意义。结论:Stathmin在脑胶质瘤微血管内皮细胞中表达随肿瘤恶性程度增高而增加,可能为脑胶质瘤的生物治疗提供一个新靶点。     

Trx通过Sirt3-P53通路促进自噬并改善高糖诱发的CMECs损伤

目的:明确硫氧还蛋白(Thioredoxin,Trx)通过自噬调节对大鼠心脏微血管内皮细胞损伤的保护作用及相关机制。方法:分离成年大鼠心脏微血管内皮细胞并分为:(1)正常对照组;(2)高糖组;(3)高糖+Trx组;(4)高糖+Trx+Ad-sh Sirt3组;(5)高糖+Trx+Ad-sh P53组;(6)高糖+DMSO空载组。通过In Vitro Vascular Permeability Assay Kit检测单层心脏微血管内皮细胞通透性,TUNEL染色检测细胞凋亡,Western blot法检测Sirt3、P53、Atg5、LC3BI/II等相关自噬相关信号通路关键蛋白的表达水平。结果:与正常对照组相比,高糖引起单层心脏微血管内皮细胞通透功能损伤,增加细胞凋亡,抑制自噬,且Sirt3、Atg5、LC3BI/II表达下降而P53表达上升;给予Trx可以上调Sirt3、Atg5、LC3BI/II蛋白表达水平,抑制P53表达,并显著减轻上述高糖引起的细胞损伤;但是,分别干扰Sirt3和P53表达后,Trx的作用明显减弱。结论:Trx通过Sirt3-P53信号通路促进心脏微血管内皮细胞自噬,降低细胞凋亡,改善高糖诱发的大鼠心脏微血管内皮细胞损伤。     

鼠脑微血管内皮细胞的分离与长期培养

采用胶原酶消化、差速离心、尼龙网滤过技术分离和获取鼠脑微血管内皮细胞,接种后4h换液使获得的内皮细胞纯化,体外进行长期培养。细胞在体外生长176天,传至30代,细胞初期成活率为92％,纯度近90％。经形态学、超微结构和免疫组化鉴定,培养细胞为血管内皮细胞。培养至第30代的细胞仍能合成和分泌PGI2、ACE等,ⅧF:Ag阳性表达,染色体为二倍体(2n=42),基本保持着细胞的主要特征。该分离和培养方法的建立,将为研究与脑血管相关疾病提供有用工具。     

Fusion of Tumour Cells with Host Cells

THE A9 cell is an 8-azaguanine-resistant derivative of the L cell line¹. It lacks the enzyme inosinic acid pyrophosphorylase and is thus unable to grow in media such as HAT² in which endogenous synthesis of nucleic acid is blocked by aminopterin. The A9 line has little ability to grow progressively in vivo. Inocula of 5 × 10⁴ to 2 × 10⁶ cells produced progressive tumours in only 12% of X-irradiated newborn syngeneic C3H mice³. One of these tumours was explanted as a cell suspension into Eagle's minimal essential medium containing 15% foetal calf serum and then subcultivated in this medium with 5% foetal calf serum. At each passage, cells were inoculated into X-irradiated newborn syngeneic C3H or semi-allogeneic C3H×X F₁ mice (X designates a number of different allogeneic parents). Between 80 and 90% of the inoculated animals developed progressive tumours. The cell line was therefore designated A9HT (high take incidence). The karyotype of the A9HT line was found to be similar to that of the A9 line, but with a slightly reduced total chromosome number. The modal chromosome number of A9HT was about 53, compared with about 57 for A9 (see ref. 4). A9 and A9HT both had between 20 and 30 bi-armed chromosomes and a number of marker chromosomes in common. A detailed comparison of the karyotypes of the two lines examined by the quinacrine fluorescence technique has been made⁵. The A9HT line, like its A9 parent, lacks inosinic acid pyrophos-phorylase and is unable to grow in HAT medium.     

树突细胞联合细胞因子诱导的杀伤细胞对急性白血病细胞的体外杀伤作用

目的:研究细胞因子诱导的杀伤细胞(CIK)与同源树突状细胞(DC)共培养后CIK细胞的表型、增殖活性的变化,及抗急性白血病细胞活性.方法:正常人外周血单个核细胞诱导DC和CIK细胞,将DC与CIK共培养,以CIK细胞单独培养为对照.用台盼蓝活细胞计数计算细胞扩增倍数,MTT法测定杀伤活性,流式细胞术分析免疫表型.结果:DC-CIK细胞增殖能力明显高于CIK细胞(P＜0.05); DC、CIK细胞共培养后,CD3+ CD8+、CD3+ CD56+双阳性细胞比率较同条件下CIK细胞组显著增多(P＜0.05);在2.5∶1-20∶1的效靶比范围内,DC-CIK共培养物对AML细胞的杀伤率显著高于CIK细胞(P＜0.05),且杀伤率与效靶比呈正相关.结论:DC-CIK细胞的增殖能力、对AML细胞的杀伤活性均高于CIK细胞,为DC-CIK细胞免疫治疗提供了实验和理论依据.     

Activation of Glioma Cells Generates Immune Tolerant NKT Cells

Therapeutic outcomes of glioma are currently not encouraging. Tumor tolerance plays an important role in the pathogenesis of glioma. It is reported that micro RNAs (miR) are associated with tumor development. This study aims to investigate the role of miR-92a in the development of tolerant natural killer T (NKT) cells. In this study, U87 cells (a human glioma cell line) and primary glioma cells were prepared. The assessment of miR-92a was performed by real time RT-PCR. The expression of interleukin (IL)-10 and IL-6 in NKT cells was evaluated by flow cytometry. Results showed that abundant IL-6⁺ IL-10⁺ NKT cells were detected in glioma tissue. Cultures of glioma cells and NKT cells induced the expression of IL-6 and IL-10 in NKT cells. Glioma cells expressed miR-92a; the latter played a critical role in the induction of IL-6 and IL-10 expression in NKT cells. The expression of the antitumor molecules, including perforin, Fas ligand, and interferon-γ, was significantly attenuated compared with control NKT cells. The IL-6⁺ IL-10⁺ NKT cells showed less capability in the induction of apoptosis in glioma cells, but showed the immune suppressor functions on CD8⁺ T cell activities. We conclude that glioma-derived miR-92a induces IL-6⁺ IL-10⁺ NKT cells; this fraction of NKT cells can suppress cytotoxic CD8⁺ T cells.     

诱导性多能干细胞与肝样细胞分化

肝脏疾病正逐渐成为全球棘手的医疗问题。肝细胞是肝脏生理活动的主要承担者,在肝脏疾病的研究以及药物的研发和测试方面有着举足轻重的作用。然而,体外分离培养的原代肝细胞面临在体外不能无限增殖和稳定表达肝脏特异基因等问题。有强大的自我更新能力和三胚层分化潜能的诱导性多能肝细胞(iPSCs)能被诱导因子、外源基因和小分子化合物等定向诱导分化为功能性肝细胞。同时,还避免了伦理、宗教以及免疫排斥等诸多问题。本文简要综述了从不同策略诱导iPSCs成为功能性肝细胞的研究方法和成果,并对该领域进行小结和展望。     

Derivation of Cardiac Progenitor Cells from Embryonic Stem Cells

Cardiac progenitor cells (CPCs) have the capacity to differentiate into cardiomyocytes, smooth muscle cells (SMC), and endothelial cells and hold great promise in cell therapy against heart disease. Among various methods to isolate CPCs, differentiation of embryonic stem cell (ESC) into CPCs attracts great attention in the field since ESCs can provide unlimited cell source. As a result, numerous strategies have been developed to derive CPCs from ESCs. In this protocol, differentiation and purification of embryonic CPCs from both mouse and human ESCs is described. Due to the difficulty of using cell surface markers to isolate embryonic CPCs, ESCs are engineered with fluorescent reporters activated by CPC-specific cre recombinase expression. Thus, CPCs can be enriched by fluorescence-activated cell sorting (FACS). This protocol illustrates procedures to form embryoid bodies (EBs) from ESCs for CPC specification and enrichment. The isolated CPCs can be subsequently cultured for cardiac lineage differentiation and other biological assays. This protocol is optimized for robust and efficient derivation of CPCs from both mouse and human ESCs.     

肿瘤干细胞及肝癌肿瘤干细胞

肿瘤干细胞理论认为只有存在于肿瘤中的少量干细胞性质的细胞群体对肿瘤发生和发展起着决定作用,肿瘤是由干细胞突变积累而形成的无限增殖的异常组织,这一理论的提出使人们对肿瘤发生机制的认识上升到了一个新的高度,也引起了研究者的广泛关注;肝癌是我国常见的恶性肿瘤之一,我国肝癌死亡率居世界之首,目前对肝癌的研究是我国恶性肿瘤防治的重点工作,现对当前肿瘤干细胞与肝癌肿瘤干细胞相关方面的最新研究进展作一概述。     

干细胞诱导分化为产胰岛素细胞的研究进展

I型糖尿病(胰岛素依赖型糖尿病)主要是由于自身免疫反应导致胰岛β细胞损伤所致。目前,临床上主要通过口服降糖药物和胰岛素替代疗法等内科措施治疗I型糖尿病,但只能延缓疾病的发展,并不能彻底治愈。迄今为止,已有研究报道利用胚胎干细胞和成体干细胞成功诱导分化为产胰岛素细胞(IPCs),这给I型糖尿病的治疗带来了新的希望。从干细胞诱导成IPCs的诱导方法都是多阶段的,因干细胞来源不同,诱导所需时间从几天到几个月差异很大,不同诱导方法中所用诱导因子也有所不同,主要包括表皮生长因子、碱性成纤维细胞生长因子、激活素A、β细胞素、尼克酰胺、Exendin-4、肝细胞生长因子、胃泌素、葡萄糖和胎牛血清等。目前,尚无统一标准诱导方法可大量并稳定的获得IPCs,并使之分泌的胰岛素量可满足临床治疗。因此,在IPCs临床应用前,关于来源干细胞的选择、诱导方法和诱导所需因子的选用仍需进一步深入探讨。本文主要就干细胞诱导分化为产胰岛素细胞的研究进展进行了综述。     

制备精原干细胞滋养层细胞条件的优化

目的:优化精原干细胞培养滋养层细胞的制备条件。方法:首先根据文献资料报道和实践经验确定丝裂霉素C作用STO细胞的浓度范围和时间范围,利用双因素优选法缩短丝裂霉素C处理STO细胞的试验范围。然后采用MTT检测法确定丝裂霉素C处理STO细胞的最佳浓度和时间。结果:滋养层细胞处理后不经过冷冻保存的情况下,17.64μg/ml 2 h处理条件的STO细胞在培养14天内细胞数量基本保持稳定,其它处理条件的细胞数量均有所增加;经冷冻保存的情况下,14.72μg/ml 2 h处理条件的STO细胞在培养14天内细胞数量基本保持稳定,其它处理条件的细胞数目均有所降低。结论:滋养层细胞处理后不经过冷冻保存的情况下,17.64μg/ml 2 h的处理条件是丝裂霉素C处理STO细胞的最佳条件;经冷冻保存的情况下,14.72μg/ml 2 h的处理条件是丝裂霉素C处理STO细胞的最佳条件。     

Increased Lysis of Stem Cells but Not Their Differentiated Cells by Natural Killer Cells; De-Differentiation or Reprogramming Activates NK Cells

The aims of this study are to demonstrate the increased lysis of stem cells but not their differentiated counterparts by the NK cells and to determine whether disturbance in cell differentiation is a cause for increased sensitivity to NK cell mediated cytotoxicity. Increased cytotoxicity and augmented secretion of IFN-γ were both observed when PBMCs or NK cells were co-incubated with primary UCLA oral squamous carcinoma stem cells (UCLA-OSCSCs) when compared to differentiated UCLA oral squamous carcinoma cells (UCLA-OSCCs). In addition, human embryonic stem cells (hESCs) were also lysed greatly by the NK cells. Moreover, NK cells were found to lyse human Mesenchymal Stem Cells (hMSCs), human dental pulp stem cells (hDPSCs) and human induced pluripotent stem cells (hiPSCs) significantly more than their differentiated counterparts or parental lines from which they were derived. It was also found that inhibition of differentiation or reversion of cells to a less-differentiated phenotype by blocking NFκB or targeted knock down of COX2 in monocytes significantly augmented NK cell cytotoxicity and secretion of IFN-γ. Taken together, these results suggest that stem cells are significant targets of the NK cell cytotoxicity. However, to support differentiation of a subset of tumor or healthy untransformed primary stem cells, NK cells may be required to lyse a number of stem cells and/or those which are either defective or incapable of full differentiation in order to lose their cytotoxic function and gain the ability to secrete cytokines (split anergy). Therefore, patients with cancer may benefit from repeated allogeneic NK cell transplantation for specific elimination of cancer stem cells.