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1.
大鼠胚胎视网膜祖细胞分离培养及其分化特性   总被引:1,自引:1,他引:0  
李艳  佘振珏  周国民 《解剖学杂志》2005,28(3):249-251,F002
目的:建立大鼠胚胎视网膜祖细胞体外培养方法并观察其分化特性。方法:取孕18d大鼠胚胎,用无血清培养技术扩增视网膜祖细胞;用免疫细胞化学、扫描电镜与透射电镜技术对祖细胞的特性及诱导分化的细胞类型进行鉴定。结果:从胚胎大鼠视网膜神经部分离的细胞具有增殖能力,可进行传代培养,获得的细胞球能表达Nestin并具有掺入BrdU的能力。诱导分化后的细胞表达,其中,Thy1.1^ 细胞最多,Opsin^ 细胞次之,GS^ 细胞较少,PKC^ 细胞少,Syntaxin^ 及Peripherin^ 细胞极少,不表达Calbindin D-28K。结论:从胚胎大鼠分离的细胞具有自我增殖能力和多向分化潜能,属于视网膜祖细胞;诱导分化产生5种视网膜细胞,以节细胞最多,未见水平细胞。  相似文献   

2.
背景:国内对视网膜干细胞的体外分离培养及鉴定仍处于初步探索阶段。 目的:体外分离、培养及鉴定新生大鼠视网膜干细胞,探讨其多向分化潜能。 方法:用神经干细胞无血清培养方法分离和培养新生24 h的SD大鼠睫状体细胞,第6代视网膜干细胞经胎牛血清诱导分化,应用免疫细胞化学方法检测视网膜干细胞的分化特性。 结果与结论:体外培养的细胞球具有连续克隆能力,Nestin抗原阳性,BrdU 标记结果显示悬浮细胞团主要由分裂增殖的细胞组成,并表达胚胎发育早期视网膜内原始细胞的特异性抗原Chx-10;诱导分化后的细胞表达星形胶质细胞特异性标志物GFAP、神经元特异性标志物NSE、感光细胞标志物Opsin、双极细胞特异性抗原PKC和节细胞特异性抗原β-tubulin,实验初步证实培养的视网膜干细胞具有神经干细胞特性,能自我更新和增殖分化成为感光细胞类型的细胞。 关键词:视网膜干细胞;细胞培养;无血清;细胞分化;大鼠 doi:10.3969/j.issn.1673-8225.2012.06.015  相似文献   

3.
目的: 大鼠视网膜干细胞的培养及鉴定。方法: 用神经干细胞无血清培养方法从出生10 d的大鼠睫状体部分离出具有单细胞克隆能力的细胞球,用MTT法检测单克隆细胞增殖能力,应用免疫组织化学的方法检测干细胞分化特性。结果: 所获得的细胞球具有连续克隆的能力,nestin抗原阳性,分化后的细胞表达星形胶质细胞、神经元、感光细胞和双极细胞特异性抗原。结论: 成功培养出大鼠视网膜干细胞。  相似文献   

4.
背景:研究已证实神经干细胞能促进脊髓损伤大鼠神经功能的恢复,但对移植细胞在体内的增殖、分化、迁移的研究有限。 目的:观察神经干细胞移植对脊髓损伤大鼠后肢运动功能修复的影响。 方法:SD大鼠制成T10脊髓全横断损伤模型,于造模成功后1周采用局部微量注射法。随机数字表法分为3组:损伤对照组仅打开椎管暴露脊髓;移植对照组:注射10 μL DMEM/F12培养液;细胞移植组:造模后移植浓度为1.0×109 L-1的神经干细胞悬液10 μL。移植后通过不同时间点BBB行为评分、病理组织学、免疫荧光技术评价大鼠脊髓功能修复情况及移植细胞在体内的存活、迁移、分化。 结果与结论:在体外成功建立SD大鼠海马源性神经干细胞培养体系;移植对照组、细胞移植组大鼠随着时间延长BBB评分均不同程度提高,从移植后2周起细胞移植组大鼠评分明显高于移植对照组(P < 0.05);神经干细胞移植后能够在体内继续存活、迁移并且分化为NF-200、GFAP表达阳性的神经元及星形胶质细胞。提示神经干细胞移植治疗脊髓损伤是一种有效的方法。  相似文献   

5.
目的: 观察视神经(ON)微挤压断后玻璃体内移植神经干细胞(NSCs)的分化情况及其对视网膜节细胞(RGCs)轴突再生的促进作用。方法: 在成年大鼠球后1 mm处微挤压断ON,在玻璃体内注入Hoechst33342标记的NSCs 2×104个,实验动物分对照组(MC组、MC+PBS组)、实验组(MC+NSCs组),各组动物分别存活3、4、5周。用粒蓝逆行标记再生的RGCs,在荧光镜下观察视网膜平铺片再生RGCs的数量变化。另取实验组5只动物存活4周后取眼球切片观察NSCs分化情况。结果: 存活3、4 、5周,再生的RGCs 数目实验组与对照组有显著差异(P<0.01)。4周后移植的NSCs表达NF、CNP、GFAP;未见NSCs迁移至视网膜内。结论: 玻璃体内注入NSCs可显著促进ON微挤压断后RGCs轴突的再生,并在玻璃体内分化为神经元、星形胶质细胞和少突胶质样细胞。  相似文献   

6.
背景:视网膜神经节细胞的损害是不可逆性视力丧失的重要原因,干细胞在此类疾病的治疗研究中显示出巨大的潜力,但关于干细胞与眼部组织关系、发挥视神经保护机制的综合性描述较少。目的:从干细胞来源及其对视网膜神经节细胞功能维持的作用出发,阐述干细胞在视网膜神经节细胞保护和再生研究中的作用与进展。方法:以“干细胞、视网膜前体细胞、视网膜祖细胞、转分化”与“视网膜神经节细胞、视网膜退行、视网膜变性”为中文关键词在万方和中国知网数据库中进行检索,以“stem cell,retinal precursor cell,retinal progenitor cell,trans differentiation”与“retinal ganglion cell,RGC,retinal degeneration”为英文关键词,分别在PubMed数据库中搜索,最终按入组标准纳入文献102篇进行综述分析。结果与结论:(1)哺乳动物眼内存在着视网膜干细胞和视网膜祖细胞,但其数量稀少、分化潜能受到限制,导致眼内视网膜神经节细胞的再生能力低下。(2)体外培养显示眼内组织中有多种细胞能直接分化为视网膜神经节细胞、另外部分细胞...  相似文献   

7.
不同时期视网膜前体细胞的培养   总被引:2,自引:0,他引:2  
姚静  孙兴怀  汪洋 《解剖学报》2007,38(5):614-617
目的 研究不同时期视网膜前体细胞的培养.方法 分离E14和E18 SD大鼠的视网膜前体细胞,用改进DMEM/F12无血清培养基悬浮培养并利用体外诱导分化、免疫细胞化学、扫描电镜和透射电镜等方法对细胞进行鉴定.结果 视网膜前体细胞在DMEM/F12无血清培养基中悬浮成球,贴壁后,细胞逐渐从细胞球向周围迁移分化.扫描电镜可见细胞球和分化细胞的形态,透射电镜可见细胞球和分化细胞的超微结构.免疫细胞化学显示,悬浮培养的细胞球中大部分细胞表达神经外胚层源性干细胞标志物nestin和细胞分裂增殖标志物BrdU.贴壁后,视网膜前体细胞能分化为多种视网膜细胞类型,包括Thy1.1阳性的视网膜神经节细胞.E14和E18视网膜神经节细胞的百分比分别为16.91%±4.05%和4.65%±1.88%,两组比较,差异有统计学意义(t=15.04,P<0.001).结论 改进DMEM/F12无血清培养基可成功培养视网膜前体细胞,培养的细胞具有无限增殖和多向分化潜能.早期视网膜前体细胞向视网膜神经节细胞分化的百分比较高.  相似文献   

8.
目的:探索通过玻璃体内细胞移植预防和治疗早产儿视网膜病(retinopathy of prematurity,ROP)的可能途径。方法:获取成年大鼠骨髓基质细胞(marrow stromal cells,MSC),并连续传代。应用免疫组织化学和ELISA技术检测MSC中及MSC条件培养基(MSC-CM)中生长因子的表达。通过体外检测内皮细胞增殖、迁移和管腔形成确认MSC-CM的作用。将DiI标记的MSCs细胞移植入氧诱导视网膜病(oxygen induced retinopathy,OIR)模型小鼠玻璃体腔。应用免疫荧光技术检测神经或胶质细胞分布与分化标志。采用视网膜整装片ADP酶组织化学染色和视网膜前内皮血管细胞核计数方法评估新生血管的抑制作用。转染血管内皮生长因子(vascular endothelial growth factor,VEGF)干扰RNA质粒的MSCs验证VEGF的保护作用。结果:体外培养的MSCs表达VEGF,胰岛素生长因子(insulin-like growth factors,IGF)和神经生长因子(nerve growth factor,NGF)。MSC-CM促进体外培养内皮细胞的增殖,迁移和管型形成。发现眼内移植后,标记的MSCs聚集在视网膜前的玻璃体内,或者整合入视网膜,并表达胶质纤维酸性蛋白(glial fibrillary acidic protein,GFAP)。吸入高氧前玻璃体内注射MSCs能显著缓解视网膜新生血管。体外和体内研究证实转染VEGF干扰RNA质粒的MSCs后其保护作用减弱。结论:在OIR早期移植MSCs能显著减少新生血管形成。VEGF等因子的旁分泌,可能在此过程发挥重要作用;通过细胞移植保护视网膜血管可以作为治疗ROP的潜在途径。  相似文献   

9.
本研究的目的是 :将体外培养的小鼠胚胎大脑皮层和脊髓的神经干细胞经单细胞悬液微移植后观察其在大鼠纹状体的存活、迁移和分化的状况。实验在无血清条件下将这些细胞扩增、培养再经活细胞荧光染料 Di I标记后 ,采用微移植的方法 ,通过脑立体定位仪上用微玻璃针将干细胞分别植入成年大鼠双侧纹状体的对称部位。大鼠存活 8周后 ,经灌注固定、恒冷箱切片 ,在荧光显微镜下观察标记的移植细胞的迁移状况 ;用星形胶质细胞特异性抗体观察移植区 GFAP的表达 ,以显示移植细胞分化状况。结果表明 :来源于胚胎小鼠大脑皮层和脊髓的体外培养神经干细胞经微移植后 ,均可在成年大鼠脑内纹状体区域存活 ,移植的神经干细胞可向周围的脑实质内迁移 ,迁移细胞沿特定的纹状体结构分布。神经干细胞主要分化成星形胶质细胞。本实验结果提示 ,移植的神经干细胞可在脑实质内存活、迁移和分化。  相似文献   

10.
背景:有研究发现硫酸软骨素酶降解硫酸软骨素蛋白多糖能够促使视网膜上Müller细胞的移行,但硫酸软骨素酶降解硫酸软骨素蛋白多糖是否能促进脂肪间充质干细胞在视网膜变性大鼠视网膜的移行尚不明确。目的:探讨硫酸软骨素酶降解硫酸软骨素蛋白多糖对脂肪间充质干细胞治疗大鼠视网膜变性的影响。方法:分离并培养人脂肪间充质干细胞,建立视网膜变性大鼠模型,向视网膜变性大鼠视网膜下腔注射脂肪间充质干细胞+硫酸软骨素酶,观察移植后大鼠脂肪间充质干细胞迁移率和视网膜细胞凋亡情况。结果与结论:人脂肪间充质干细胞能够成功培养,Brd U对人脂肪间充质干细胞的标记率达90.0%以上。建模后7 d,视网膜外核层塌陷,光感受器细胞大量外节迸解,外核层贴附在Bruch’s膜上,视网膜呈拱桥样,中央视网膜和外周视网膜均受到损伤;正常大鼠视网膜各层清晰,光感受器细胞排列规律,视网膜色素上皮层完整。脂肪间充质干细胞+硫酸软骨素酶组脂肪间充质干细胞迁移率高于脂肪间充质干细胞组,且2组视网膜细胞凋亡率比较差异无显著性意义。表明硫酸软骨素酶降解硫酸软骨素蛋白多糖可提高人脂肪间充质干细胞在视网膜上的迁移能力。  相似文献   

11.
Retinal dystrophies are rarely curable diseases and several avenues of research are being pursued, such replacement therapies and pharmacological treatment. Among them, the transplantation of functional retinal cells has been envisaged in order to restore vision in patients who have these diseases by repopulating the damaged retina and/or by rescuing retinal neurons from further degeneration. Over the past few years, identification and characterization of stem cells has opened new avenues in cell-replacement therapy. Since retinal stem cells are already present during embryonic development, they persist in the adult mammalian eye only in the ciliary marginal zone, even a stem cell potential has been described for the Müller glia in the retina. This result opened possibilities of regeneration by mobilizing endogenous stem cells to respond to injury. Regarding the transplantation studies, in all experiments using different types of stem cells (retinal progenitors, neural stem cells, bone marrow-derived stem cells and ES cells), despite their incorporation within the host's retina, the transplanted cells failed to express retina-specific markers and to establish synaptic connections. Therefore, the true potential of the different stem cells in retina repair can only be realized with more information about mechanisms that regulate their proliferation and differentiation; and by development of techniques that allow their prospective identification and enrichment.  相似文献   

12.
Retinal degeneration is a leading cause of irreversible blindness in the developed world. Differentiation of retinal cells, including photoreceptors, from both mouse and human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), potentially provide a renewable source of cells for retinal transplantation. Previously, we have shown both the functional integration of transplanted rod photoreceptor precursors, isolated from the postnatal retina, in the adult murine retina, and photoreceptor cell generation by stepwise treatment of ESCs with defined factors. In this study, we assessed the extent to which this protocol recapitulates retinal development and also evaluated differentiation and integration of ESC-derived retinal cells following transplantation using our established procedures. Optimized retinal differentiation via isolation of Rax.GFP retinal progenitors recreated a retinal niche and increased the yield of Crx(+) and Rhodopsin(+) photoreceptors. Rod birth peaked at day 20 of culture and expression of the early photoreceptor markers Crx and Nrl increased until day 28. Nrl levels were low in ESC-derived populations compared with developing retinae. Transplantation of early stage retinal cultures produced large tumors, which were avoided by prolonged retinal differentiation (up to day 28) prior to transplantation. Integrated mature photoreceptors were not observed in the adult retina, even when more than 60% of transplanted ESC-derived cells expressed Crx. We conclude that exclusion of proliferative cells from ESC-derived cultures is essential for effective transplantation. Despite showing expression profiles characteristic of immature photoreceptors, the ESC-derived precursors generated using this protocol did not display transplantation competence equivalent to precursors from the postnatal retina.  相似文献   

13.
胚胎干细胞裸鼠眼内诱导形成髓上皮瘤   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:观察小鼠胚胎干细胞在裸鼠眼内生长的形态变化。方法:将胚胎干细胞在体外培养,并维持在未分化的状态,再移植到Balb/c裸小鼠眼内。6-45d处死裸鼠,形态学和免疫组化观察其变化。结果:胚胎干细胞移植到裸小鼠右眼后,在眼前房和玻璃体腔内生长。形态学检查在前房和玻璃体腔内见到各种形态的细胞,出现囊样、腺样、管样、菊花样等结构。免疫组化NSE染色多数细胞呈强阳性反应,部分细胞GFAP也呈中强度阳性反应。结论:胚胎干细胞D3株在Balb/c裸小鼠眼内发育分化成了髓上皮瘤样组织。  相似文献   

14.
背景:视网膜疾病以视网膜细胞损伤或凋亡为特点,缺乏理想的治疗方法。诱导多功能干细胞具有自我更新和多向分化潜能,不存在伦理道德问题,为干细胞移植治疗提供了新的来源,是当前研究的热点。 目的:综述诱导多功能干细胞在视网膜疾病治疗中应用的研究进展。 方法:第一作者应用计算机检索PubMed 相关文献,检索时间为2006年至2011年,检索词“induced pluripotent stem cells,retinal,photoreceptor,retinal pigment epithelium,retinal ganglion cell”并限定文献语言种类为English。共纳入42篇文章进行综述。 结果与结论:诱导多功能干细胞可以诱导分化为视网膜细胞,为细胞移植治疗提供来源,也可以作为疾病的模型来研究发病机制或者药物筛选,因此诱导多功能干细胞治疗视网膜疾病具有很大前景。然而,体细胞成功诱导为诱导多功能干细胞的效率低,并且存在致瘤的风险,有待更进一步研究。  相似文献   

15.
背景:骨髓间充质干细胞向神经细胞诱导分化可为神经系统受损伤后的修复和再生带来了新的希望。 目的:探讨骨髓间充质干细胞在视网膜干细胞培养上清液诱导条件下向神经元细胞分化。 方法:采用全骨髓培养方法,用视网膜干细胞培养上清液诱导骨髓间充质干细胞,通过免疫荧光染色鉴定其分化的结果。 结果与结论:诱导72 h,骨髓间充质干细胞表达神经干细胞的特异性抗体巢蛋白和神经元中的标志性微管相关蛋白微管相关蛋白2。视网膜干细胞培养上清液能够促进骨髓间充质干细胞向神经元样细胞分化,提示视网膜干细胞可能分泌神经生长因子。  相似文献   

16.
We previously reported that transfection of Pax6 gene which regulated early events in eye development into mouse ES cells brought about their differentiation into retinal progenitors. Here, we attempted to establish cloned retinal progenitors which had ability to further differentiate into photoreceptor like cells by transfecting mouse induced pluripotent stem (iPS) cells with Pax6 gene. Undifferentiated iPS cells were transfected with Pax6 cDNA, followed by selection with G418. After limiting dilution culture, we selected cloned Pax6-transfected cells, which simultaneously expressed mRNAs of Nestin, Musashi1, Six3 and Chx10 for further characterization. We obtained totally 8 clonally expanding Pax6-transfected cells. They started to express mRNAs of Brn3b, Cone-rod homeobox (Crx), pkc, CD73, rhodopsin and the γ-subunit of rod cGMP phosphodiesterase (PDEγ). Flow cytometric analysis revealed that almost half of the cells were CD73+, a marker of photoreceptor precursors. Western blotting confirmed cytoplasmic protein expression of rhodopsin. High KCl stimulation increased free Ca influx into the cells on Ca2+ imaging. iPS cells transfected with Pax6 gene, followed by subsequent limiting dilution culture became retinal progenitors including photoreceptor like cells. The cloned cell lines may be useful for analyzing differentiation requirement of retinal progenitors.  相似文献   

17.
骨髓间充质干细胞对成年大鼠视网膜节细胞再生的影响   总被引:4,自引:1,他引:3  
项平  黄锦桃  李海标 《解剖学杂志》2005,28(3):252-254,272
目的:探讨骨髓间充质干细胞(MSCs)对受损成年大鼠视网膜节细胞(RGCs)轴突再生的影响。方法:切断大鼠视神经,缝接自体坐骨神经(AG)。动物分对照组、AG MSCs组、AG MSCs tPNS(三七总皂苷)组。各组动物存活3、4周,用粒蓝逆行标记再生的RGCs,荧光镜下观察视网膜平铺片中再生RGCs的数量变化。免疫组化检测MSCs在玻璃体内的分化。结果:动物存活3、4周,再生的RGCs数目实验组与对照组有显著性差异。AG MSC组和AG MSCs tPNS组,存活的细胞表达Vimentin、NF和GFAP,Laminin无表达。结论:玻璃体植入MSCs可促进受损伤的视网膜节细胞轴突再生。  相似文献   

18.
Kumar R  Dutt K 《Tissue engineering》2006,12(1):141-158
One approach to the treatment of retinal diseases, such as retinitis pigmentosa, is to replace diseased or degenerating cells with healthy cells. Even if all of the problems associated with tissue transplant were to be resolved, the availability of tissue would remain an ongoing problem. We have previously shown that transformed human retinal cells can be grown in a NASA-developed horizontally rotating culture vessel (bioreactor) to form three-dimensional-like structures with the expression of several retinal specific proteins. In this study, we have investigated growth of non-transformed human retinal progenitors (retinal stem cells) in a rotating bioreactor. This rotating culture vessel promotes cell-cell interaction between similar and dissimilar cells. We cultured retinal progenitors (Ret 1-4) alone or as a co-culture with human retinal pigment epithelial cells (RPE, D407) in this system to determine if 3D structures can be generated from non-transformed progenitors. Our second goal was to determine if the formation of 3D structures correlates with the upregulation of neurotrophins, basic fibroblast growth factor (bFGF), transforming growth factor alpha (TGFalpha), ciliary neurotrophic factor (CNTF), and brain-delivered neurotrophic factor (BDNF). These factors have been implicated in progenitor cell proliferation, commitment, differentiation, and survival. We also investigated the expression of the following retinal specific proteins in this system: neuron specific enolase (NSE); tyrosine hydroxylase (TH); D(2)D(3), D(4) receptors; protein kinase-C alpha (PKCalpha), and calbindin. The 3D structures generated were characterized by phase and scanning transmission electron microscopy. Retinal progenitors, cultured alone or as a co-culture in the rotating bioreactor, formed 3D structures with some degree of differentiation, accompanied by the upregulation of bFGF, CNTF, and TGFalpha. Brain-derived neurotrophic factor, which is expressed in vivo in RPE (D407), was not expressed in monolayer cultures of RPE but expressed in the rotating bioreactor-cultured RPE and retinal progenitors (Ret 1-4). Upregulation of neurotrophins was noted in all rotating bioreactor-cultured cells. Also, upregulation of D(4) receptor, calbindin, and PKCalpha was noted in the rotating bioreactor-cultured cells. We conclude that non-transformed retinal progenitors can be grown in the rotating bioreactor to form 3D structures with some degree of differentiation. We relied on molecular and biochemical analysis to characterize differentiation in cells grown in the rotating bioreactor.  相似文献   

19.
Retinal photoreceptor degeneration was induced by exposing albino rats to fluorescent illumination at elevated environmental temperatures. Fine carbon particles were injected intravenously or directly into the vitreous body or anterior chamber of the eye. The resulting pattern of invasion, migration, and egression of carbon-filled phagocytes in eyes with degenerated retinas was reconstructed from a time sequence series of light and electron microscopic tissue sections. Retinal debris, such as damaged photoreceptor outer segments and carbon particles, was most frequently removed by two populations of cells possessing phagocytic properties: mononuclear cells of vascular origin and pigment epithelial cells. After retinal damage, mononuclear cells appeared first in the vitreous body and later, in time sequence, progressively deeper in the inner plexiform layer and out to the bipolar nuclear layer, where they were seen within, or partially within, retinal capillaries. After intravenous carbon injection, however, marked phagocytes were not seen in the retina. Carbon-filled phagocytic cells were observed in the choroidal connective tissue and blood vessels after intravenous injection, but not after intravitreal injections of carbon. Therefore, retinal phagocytes did not appear to leave the eye through the choroidal circulation. Pigment epithelial cells proliferated by mitotic activity, occurred as single cells separated from Bruch's membrane, and were seen among the degenerated outer segments. After direct exposure to carbon particles, pigment cell phagosomes contained both carbon and lamellated discs of degenerated outer segments. Whether these cells exited from the eye through retinal capillaries or returned to Bruch's membrane to reestablish continuity in the pigment epithelium could not be determined.  相似文献   

20.
Transplantation of retinal cells has recently provided a promising therapeutic approach for retinal degeneration. Here, we differentiated initially retinal progenitors (RPs) from adherent feeder-free human embryonic stem cells (hESCs) with the use of defined media supplemented with a specific combination of growth factors. The differentiated RPs highly (>80%) expressed related molecular features that included Six3 at an early stage in addition to Crx, Rx, Pax6, Otx2, and Chx10 at later stage. Next, we examined the induction of photoreceptors by Shh and/or the coculture of rabbit retinal pigmented epithelium with hESCs-derived RPs. The differentiation of retinal cells was demonstrated by protein and gene expression in all groups. However, S-Opsin, a cone photoreceptor marker, had higher expression in the presence of Shh, whereas expressions of Gli and Hes1 decreased in the same group. Finally, hESC-derived RPs were treated with Shh transplanted into the subretinal space of sodium iodate-injected albino-type adult rabbits and analyzed 4 weeks later. Transplanted retinal cells survived, migrated into retinal layers, and restored a small but significant B-wave. The grafted cells expressed photoreceptor markers, S-Opsin and Rhodopsin. Our results indicate that putative hESC-derived retinal cells express related genes and proteins. Further, our results show that retinal-like cells can be useful replacements for photoreceptors in retinal diseases.  相似文献   

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