脐带间充质干细胞向汗腺样细胞分化后的表型变化

目的：比较人脐带间充质干细胞（hUC-MSCs）向汗腺样细胞诱导前后表型特征的变化.方法：对hUC-MSCs进行分离、培养、鉴定,通过显微镜观察、免疫细胞化学、流式细胞术等方法比较hUC-MSCs经汗腺分化诱导培养液培养前后细胞形态变化及癌胚抗原（CEA）、角蛋白7（CK7）、CK8、CK14、CK18、CK19表达的差异.结果：hUC-MSCs向汗腺样细胞诱导前呈梭形,呈成纤维细胞样;流式细胞仪检测发现CD29、CD90表达阳性;而CD34、CEA、CK14、CK19表达阴性.经汗腺诱导培养基诱导后hUC-MSCs分化为外形肥大、不规则、类似铺路石样的细胞,聚集性增殖;免疫细胞化学检测显示CK7、CK8、CK18抗原表达阳性;流式细胞仪检测结果显示CEA、CK14、CK19的阳性表达率分别为77.98%,48.47%,20.85%.结论：hUC-MSCs经过汗腺分化诱导培养基培养后能够分化为表达汗腺细胞标记物抗原的汗腺样细胞.     

人骨髓间充质干细胞向汗腺样细胞诱导分化的研究

目的：观察体外热休克汗腺细胞（SGCs）和人骨髓间充质干细胞（BM-MSCs）共培养体系中 BM-MSCs的形态和表型变化,为进一步表观遗传学表达谱的检测及汗腺诱导关键转录因子的研究提供实验基础。方法：体外分离、培养、扩增人BM-MSCs和 SGCs,成骨和成脂诱导分化以鉴定BM-MSCs 的分化功能。在 Tran-swell间接共培养体系中,培养的BM-MSCs和经47℃高温处理造成热休克的 SGCs 在 Transwell 板中间接共培养;在Transwell＋诱导因子共培养体系中,上室的BM-MSCs培养基中添加了汗腺诱导因子（无汗性外胚叶发育不良蛋白、重组人表皮生长因子和胰岛素-转铁蛋白-亚硒酸钠）。监测共培养过程中BM-MSCs的细胞形态变化,免疫荧光法检测诱导后BM-MSCs的表型改变。结果：经与热休克 SGCs 共培养诱导10 d后,部分 BM-MSCs 有由长梭形变为扁平状多边形的趋势,且局部细胞间连接紧密成片。BM-MSCs 诱导前不表达 CEA 和 CK19;BM-MSCs诱导后,Transwell间接共培养体系部分细胞 CEA 和 CK19表达阳性,Transwell＋诱导因子共培养体系CEA和CK19阳性细胞数明显多于 Transwell 间接共培养体系。结论：热休克汗腺细胞与 BM-MSCs 在 Tran-swell间接培养以及相关汗腺诱导因子的共培养体系下,BM-MSCs呈现向 SGCs诱导分化趋势。     

蜕皮甾酮对人脐带间充质干细胞冻存复苏后生物学活性的影响

目的：研究体外条件下蜕皮甾酮（EDS）对冻存复苏后人脐带间充质干细胞（hUCMSCs）生物学活性的影响。方法：hUCMSCs采用梯度冷冻技术冻存,6个月后复苏,扩增、传代,分3组培养：空白对照组用普通培养基培养;低剂量EDS组在普通培养基中加入100μg／mlEDS;高剂量EDS组在普通培养基中加入200μg／mlEDS。显微镜下观察细胞形态,10d时计算克隆形成能力,绘制细胞生长0～7d的细胞生长曲线,流式细胞仪鉴定hucMscs的细胞表面特异标记（CD34、CD45、CD29、CD105）,油红0染色及茜素红染色观察huCMSCs向脂肪细胞、成骨细胞分化的能力。结果：两EDS组克隆形成率约为75％,空白对照组约为40％。生长曲线显示两EDS组增殖速度较空白对照组快,但两EDS组增殖速度相近。流式检测结果显示两EDS组的CD29、CD105阳性率明显高于空白对照组,CD34、CD45里阴性表达,其表达明显低于空白对照组（P〈0．05）,两EDS组之间差异无统计学意义;成骨、成脂分化能力检测发现,各组细胞均能够向脂肪细胞、成骨细胞分化,而高剂量EDS组细胞在未加诱导培养基的情况下仍出现向成骨细胞分化的趋势。结论：在一定浓度范围内,EDS对细胞复苏后恢复细胞活性以及提高存活率方面具有积极作用,但是较高浓度的EDS有诱导细胞向成骨细胞方向分化的趋势。     

冻存复苏人脐带间充质干细胞体外扩增和向脂肪细胞分化的研究

目的：分离培养人脐带间充质干细胞（human Umbilical Cord Mesenchymal Stem Cells hUCMSCs）,观察其冻存复苏后向脂肪细胞定向分化的能力。方法：将剔除动静脉的新鲜人脐带组织切成小块培养,得到贴壁细胞,观察细胞生长及检测其表面抗原。将第1代的hUCMSCs采用梯度冷冻技术冻存5个月,复苏后培养至第12代时,加入成脂诱导剂培养。当诱导至21天时行油红O染色,7天及14天时用RT—PCR技术分别检测成脂转化基因过氧化物酶增殖剂受体（PPAR γ-2）和脂蛋白酯酶（LPL）。结果：组织块培养法收获的单个核细胞培养传代后,能获得均一贴壁的间充质干细胞,hUCMSCs冻存复苏后,活细胞约为86％,流式细胞仪分析这些细胞表达CDI3、CD44和CD71等MSCs标志物,不表达CD14、CD34和HLA—DR表面抗原。复苏细胞在成脂诱导剂的作用下,细胞中有脂滴产生,通过油红0染色显示细胞核周围有脂滴聚集,通过RT—PCR检测有LPL及PPARγ2 mRNA的表达。结论：采用组织块贴壁培养法分离获得的人脐带间充质干细胞可冷冻保存。复苏后培养至第12代仍具有向脂肪细胞分化的潜能,可作为脂肪组织工程种子细胞来源。     

汗腺再生的研究进展

<正>严重皮肤烧、创伤的治疗目的是加快创面愈合速度和提高创面愈合质量。目前,加快创面愈合速度的问题已基本得到解决,而人们则越来越重视创面愈合的质量,即如何减少瘢痕和重建皮肤附属器,更好地恢复皮肤功能。汗腺功能的恢复具有重要的意义,本文回顾了近年来汗腺再生的研究进     

干细胞及组织工程诱导皮肤汗腺再生的研究进展

皮肤作为哺乳动物最大器官,是抵御外界刺激的第1道防护屏障。汗腺是皮肤重要附属器之一,在维持电解质平衡和调节体温方面起着重要作用。大面积深度烧伤患者通常损伤会达真皮深层甚至皮肤全层,损伤汗腺修复困难,甚至无法再生,患者排汗和体温调节功能受到严重影响,生活质量降低。如何实现汗腺的功能化成为损伤皮肤再生医学的重要研究内容之一...     

不同冻存液对人脐带间充质干细胞生物学特性的影响

观察不同冻存液对人脐带间充质干细胞(human umbilical cord mesenchymal stem cell,hUC-MSC)冻存复苏后生物学特性的影响,优化冻存方法.方法 脐带取自2011年1月至2011年12月在中山大学附属第三医院产科剖宫产的足月健康产妇.从脐带分离得到的hUC-MSC培养传代,取第3代细胞.根据冻存液不同分为3组,A组冻存液为二甲基亚砜(dimethyl sulfoxide,DMSO):胎牛血清(fetal bovine serum,FBS):低糖杜氏培养基(low glucose Dulbecco's modified Eagle's medium,LG-DMEM)为1∶2∶7,B组为DMSO:FBS:LG-DMEM为1∶5∶4,C组为DMSO∶ FBS为1∶9,不含LG-DMEM.经冻存12个月,复苏细胞,以第3代未冻存细胞悬液作为对照组,采用台盼蓝染色法比较hUC-MSC的细胞存活率,采用噻唑蓝(methyl thiazolyl tetrazolium,MTT)法比较细胞的生长情况绘制生长曲线,倒置显微镜下观察细胞的生长状况,采用流式细胞仪检测各组细胞的表面标记.结果 A、B、C三组的细胞存活率分别为(20±4)%、(71±8)%和(85±7)%.与C组比较,A组和B组的细胞存活率降低,差异有统计学意义(均为P <0.05).细胞生长曲线显示,与对照组相比,C组hUC-MSC在各时间点细胞生长迅速,但差异无统计学意义(P>0.05);B组hUC-MSC在24 h、48 h、72 h细胞生长差异无统计学意义(P>0.05),在96 h时间点生长速率低于对照组,差异有统计学意义(P<0.05);而A组hUC-MSC在各个时间点细胞生长减慢,差异有统计学意义(均为P<0.05).形态学观察显示,A组细胞胞体宽大多角,并且较多分支,B组和C组细胞饱满,折光性好,呈长梭形、纺锤形或多角形.A组细胞复苏后细胞数目过少无法进行表面标记,B组和C组hUC-MSC表面标记物CD31、CD34、CD45、人类白细胞抗原(HLA)-DR表达阴性,CD105、CD90、CD44表达阳性.结论 含高浓度血清的冻存液适合hUC-MSC的长期保存,含90% FBS的冻存液为hUC-MSC的最佳冻存保护液.     

间充质干细胞在肝再生研究中的应用

间充质干细胞(mesenchymal stem cells,MSCs)移植治疗肝损伤及肝衰竭已取得令人瞩目的成就.但是,细胞定植能力弱以及潜在致瘤性、促纤维化的可能,阻碍了MSCs的临床应用.因此,有必要探索更优化的治疗方式,以提高MSCs治疗的安全性及有效性.迄今,MSCs来源的肝细胞、基因修饰的MSCs及MSCs培养液成分运用促进肝再生已取得鼓舞人心的成果.本文就近些年MSCs在肝再生研究中的应用作一综述.     

黄芪诱导人脐带间充质干细胞分化为神经样细胞的实验研究

目的 研究原代人脐带间充质干细胞(UCMSCs)的生物学特性及其体外向神经细胞诱导分化的条件,为组织化人工神经的制备提供干细胞资源.方法 无菌条件下从人脐带华尔通胶(Wharton jelly)分离并贴壁培养人UCMSCs,免疫组化技术检测UCMSCs表面特异标志物表达;四组细胞分别加入单纯培养液空白对照组(A组)、单纯生长因子诱导组(B组)、单纯黄芪诱导组(C组)和黄芪联合生长因子诱导液(D组),倒置显微镜下观察其形态并检测NSE、NF和GFAP的阳性表达,结果进行统计学分析.结果 人UCMSCs表面标记CD29、CD44、CD105强阳性,CD106弱阳性,CD34、CD45阴性,符合人UCMSCs的特征;人UCMSCs经黄芪诱导后细胞表面GFAP、NSE均为强阳性表达.结论 人UCMSCs可以在体外采用组织块贴壁培养法培养成功,黄芪可将人UCMSCs成功的诱导为神经样细胞,为组织化人工神经的制备和周围神经缺损的治疗提供了新的方法.

Abstract：

Objective To investigate the biological characteristics of human umbilical cord derived mesenchymal stem cells(UCMSCs) and inducing them to differentiate into neurons in vitro,in order to provide stem cell resource for the tissue engineering artificial nerve. Methods UCMSCs were cultured from Wharton jelly of human umbilical cord in the condition of sterilitas,surface antigens of UCMSCs were detected by immunohistochemistry.The frist group of cells were added by virgin nutrient,the second group of cells were induced by merely growth factors,the third of cells were induced by merely astragalus mongholicus and the fourth by the astragalus mongholicus with growth factor,observed the morphology of the cells of the two groups under inverted microscope,and determine the positive expression rate of nerve cells' markers,such as NSE,NF and GFAP.The results were statistically analyzed.Results UCMSCs were strongly positive for CD29,CD44,CD105,weakly positive for CD105 and negative for CD34,CD45.After induced by Astragalus mongholicus,UCMSCs were strongly positive for GFAP,NSE. Conclusion UCMSCs can be successfully cultured from the adherent tissue pieces,Astragalus mongholicus can successfully induce them to differentiate into neurons in vitro,to provide a new method of making the tissue engineering artificial nerve and treat theperipheraly nervus defect.     

CD34+细胞在干细胞旁分泌下向内皮细胞分化的研究

目的 探讨人脐血CD34+细胞在脐带间充质干细胞(UC-MSCs)旁分泌作用下向内皮细胞诱导分化的可行性.方法 收集20份脐血,体积(103.80±19.77)ml.免疫磁珠(MACS)分选CD34+细胞;取脐带用消化贴壁法获得UC-MSC.流式鉴定干细胞表型.实验分单纯培养组、诱导组、共培养组.结果 流式鉴定CD34+细胞纯度(95.02±3.81)%.培养14 d流式检测共培养组表达CD31、CD144、VWF分别为(65.43±5.61)%、(54.40±4.13)%、(47.53±3.96)%(与单纯培养组比较P＜0.05),部分表达CD34,阴性表达CD45,这与诱导组及成熟脐静脉内皮细胞表达率一致.结论 UC-MSCs旁分泌作用与外源性细胞因子都具有促分化作用,均能使脐血CD34+细胞向内皮细胞分化.

Abstract：

Objective To study whether the paracrine action of umbilical cord-derived mesenchymal stem cells (UC-MSC) can induce differentiation of human umbilical cord blood-derived CD34+ cells into endothelial cells in vitro. Methods The 20 fresh umbilical cord blood samples were collected with volume of (103. 80 ± 19. 77) ml. CD34+ cells were isolated from the mononuclear cells by magnetic activated cell sorting system (MACS) , and mesenchymal stem cells (MSCs) were isolated from umbilical cord by collagenase and trypsin digestion. Three groups were set up: CD34+ cells pure culture group, cytokineinduced group and two stem cells co-culture group with noncontact. Results The average purity of enriched CD34+ cells as assessed by FACS was (95. 02 ± 3. 81) %. Freshly isolated CD34+ cells were small and round which suspended in culture medium. Attached cord-like structure cells of CD34+ cells appeared after 7 days coculture with noncontacted MSC, and when the CD34+ cells grew into large number, they formed colonies. These cells expressed endothelial specific markers, including CD144 (54. 40 ±4. 13)% ,vWF (47. 53 ± 3. 96) % , CD31 (65. 43 ± 5. 61) % ( P ＜ 0. 05, as compared with CD34+ cells pure culture group) , partially expressed CD34 and, the leukocyte common antigen CD45 was negatively expressed.Conclusion Human umbilical cord blood-derived CD34+ cells could be induced into endothelial cells under the paracrine action of umbilical cord-derive mesenchymal stem cells which has the same effect of cytokines.     

人脐带间充质干细胞分泌物对肝细胞增殖和凋亡的影响

Objective To investigate the effect of human umbilical cord mesenchymal stem cell paracrine substance on proliferation and apoptosis of liver cells in vitro. Methods Mesenchymal stem cells (MSC)were separated from human umbilical cord with type Ⅳ collagenase and trypsogen digestion method and cultured in vitro. The human umbilical cord mesenchymal stem cells-conditioned medium(MSC-CM) which contain paracrine substance of human umbilical cord mesenchymal stem cells (HUCMSC) was prepared. Hepatocytes were isolated from SD rats by low concentration collagenase perfusion procedure. There were three groups in the experiment, control group, 2% MSC-CM group and 8% MSC-CM group. The proliferation of normal hepatocytes were assayed with MTT method. We detected the urea and albumin level in culture supernatant to assay the hepatocyte function under different concentration MSC-CM. Hepatocytes were induced for apoptosis by Actinomycin D and tumor necrosis factor alpha (TNF-α),and the apoptosis effect of different concentration MSC-CM was assayed with LIVE/DEAD Viability/Cytotoxicity Kit. Results The MTT assay showed that the absorbance of 2% MSC-CM group was significantly increased (P＜0. 01), and the urea and albumin levels of 2 % MSC-CM group were also significantly increased when compared with control group(P＜0. 01).LIVE/DEAD Viability/Cytotoxicity Kit revealed that hepatocyte survival rate of 2 % MSC-CM group was increased when compared with control group(P＜0. 05), there were no significant differences in above-mentioned experiments when 8% MSC-CM group compared with control group. Conclusion The low concentration MSC-CM could stimulate normal hepatocyte proliferation, inhibit impaired hepatocyte apoptosis and improve hepatocyte function.     

人脐带间充质干细胞分泌物对肝细胞增殖和凋亡的影响

Objective To investigate the effect of human umbilical cord mesenchymal stem cell paracrine substance on proliferation and apoptosis of liver cells in vitro. Methods Mesenchymal stem cells (MSC)were separated from human umbilical cord with type Ⅳ collagenase and trypsogen digestion method and cultured in vitro. The human umbilical cord mesenchymal stem cells-conditioned medium(MSC-CM) which contain paracrine substance of human umbilical cord mesenchymal stem cells (HUCMSC) was prepared. Hepatocytes were isolated from SD rats by low concentration collagenase perfusion procedure. There were three groups in the experiment, control group, 2% MSC-CM group and 8% MSC-CM group. The proliferation of normal hepatocytes were assayed with MTT method. We detected the urea and albumin level in culture supernatant to assay the hepatocyte function under different concentration MSC-CM. Hepatocytes were induced for apoptosis by Actinomycin D and tumor necrosis factor alpha (TNF-α),and the apoptosis effect of different concentration MSC-CM was assayed with LIVE/DEAD Viability/Cytotoxicity Kit. Results The MTT assay showed that the absorbance of 2% MSC-CM group was significantly increased (P＜0. 01), and the urea and albumin levels of 2 % MSC-CM group were also significantly increased when compared with control group(P＜0. 01).LIVE/DEAD Viability/Cytotoxicity Kit revealed that hepatocyte survival rate of 2 % MSC-CM group was increased when compared with control group(P＜0. 05), there were no significant differences in above-mentioned experiments when 8% MSC-CM group compared with control group. Conclusion The low concentration MSC-CM could stimulate normal hepatocyte proliferation, inhibit impaired hepatocyte apoptosis and improve hepatocyte function.     

人脐带间充质干细胞分泌物对肝细胞增殖和凋亡的影响

目的 探讨人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,HUC MSC)旁分泌物质在体外对肝细胞再生和凋亡的影响.方法 利用Ⅳ型胶原酶和胰酶消化法从脐带中分离间充质干细胞,制备含有HUCMSC旁分泌物质的条件培养基(mesenchymal stem cells-conditioned medium,MSC-CM),采用低浓度胶原酶原位循环灌流法分离肝细胞.试验分为对照组、2%MSC-CM组和8%MSC-CM组三组.采用MTT比色法观察不同浓度MSC-CM对正常肝细胞增殖的影响.测定上清中尿素、白蛋白的含量,观察不同浓度MSC-CM对肝细胞功能的影响.利用放线菌素D和肿瘤坏死因子α诱导肝细胞凋亡,采用细胞活性分析试剂盒检测不同浓度MSC-CM对肝细胞凋亡的影响.结果 与对照组比较,2%MSC-CM组吸光度(A)540nm值(P＜0.01)以及上清尿素和白蛋白含量显著升高(P＜0.01),肝细胞存活率增加(P＜0.05);8%MSC-CM组与对照组无显著差异.结论 低浓度的MSC-CM在体外可以刺激正常肝细胞再生,抑制受损肝细胞凋亡,改善肝细胞功能.     

脐带间充质干细胞移植治疗急性脊髓损伤的临床价值

目的:探讨脐带间充质干细胞移植(umbilical cord mesenchymal stem cells,UC-MSC)治疗急性脊髓损伤(acute spinal cord injury,ASCI)的临床价值。方法:选择2017年1月～2018年1月我院收治的50例ASCI患者作为研究组,同时以同期的50例ASCI患者作为对照组。所有患者在受伤后72h内进行减压内固定术,对照组患者给予抗炎、脱水、抗感染及神经营养等常规治疗,研究组患者在对照组的基础上采用腰穿鞘内注射脐带间充质干细胞。比较治疗前及治疗后3、6、12个月两组的功能指标恢复情况,包括ASIA分级与评分、Botsford及脊髓损伤独立量表Ⅲ(spinal cord independence measureⅢ,SCIM-Ⅲ)评分、T细胞亚群(CD3+、CD4+、CD8+、CD4+/CD8+)、免疫球蛋白(Ig G、Ig A、Ig M),观察不良反应(头痛、发热、胃肠功能紊乱、尿路感染等)发生情况。结果:治疗后3、6、12个月,两组的ASIA等级改善率、ASIA运动评分、ASIA感觉评分、Botsford评分及SCIM-Ⅲ评分均呈不断增高趋势(P0.05),CD3+、CD4+、CD4+/CD8+水平呈不断降低趋势(P0.05),CD8+、Ig G、Ig A、Ig M水平均无明显变化(P0.05),研究组的ASIA等级改善率、ASIA运动评分、ASI感觉评分、Botsford评分及SCIM-Ⅲ评分均明显高于对照组(P0.05),两组之间的CD3+、CD4+、CD8+、CD4+/CD8+、Ig G、Ig A、Ig M水平比较差异无统计学意义(P0.05);研究组与对照组的不良反应发生率分别为18.0%、14.0%,两组间比较差异无统计学意义(P0.05)。结论:间充质干细胞能够明显促进ASCI患者的神经功能恢复,不影响体液免疫且不增加不良反应发生率。     

脐带间充质干细胞对重度烧伤大鼠肾脏保护作用的研究

目的：观察脐带间充质干细胞（UCMSCs）移植对大鼠严重烧伤后肾脏损伤的影响,为干细胞应用于烧伤后的脏器保护研究奠定基础。方法：获取并分离培养孕大鼠UCMSCs并用流式细胞技术鉴定细胞表面抗原。48只SD大鼠随机分为4组：正常对照组（n=12）、生理盐水组（n=12）、乌司他丁组（n=12）和UCMSCs组（n=12）。正常对照组不作任何处理,立即活杀取材;其余3组制备20％TBSAIII度烧伤模型（98℃,12s）,于伤后48h分别静脉注射生理盐水0．1ml／g（生理盐水组）、乌司他丁1．6×105U／kg（乌司他丁组）和UCMSCs106／k（uCMSCs组）,于给药后7、14d观察大鼠肾脏组织病理学,免疫组化法观察组织凋亡相关蛋白Bcl-2的表达,并进行血尿素氮（BUN）、肌酐（cr）水平的测定。结果：烧伤后7、14d的组织病理学观察显示,干细胞移植后的大鼠烧伤后肾脏组织充血、肿胀等病理学改变较乌司他丁组及生理盐水组有所减轻,随时间延长减轻更加明显;免疫组化观察显示UCMSCs组伤后7d和14d肾组织中Bcl-2的表达较乌司他丁组和生理盐水组明显增多,表明肾组织抗凋亡能力增强。大鼠烧伤后BUN和Cr均较正常对照组显著升高。乌司他丁治疗组除14dBUN较生理盐水组升高外,其余时间BUN和Cr均明显下降。UCMSCs组伤后7和14d两肾功能指标均明显下降,与生理盐水组和乌司他丁组比较差异均有显著性（P〈0．05）,显示干细胞治疗对肾功能有明显改善作用。结论：UC—MSCs移植可有效减轻重度烧伤后大鼠‘肾脏组织的损伤并改善肾脏功能。     

人脐带间充质干细胞与自体激活雪旺细胞联合移植修复脊髓损伤的实验研究

目的 通过观察人脐带间充质干细胞(hUCMSCs)和大鼠自体激活雪旺细胞(AASCs)联合移植修复脊髓损伤的疗效,探讨AASCs对hUCMSCs体内存活、分化的影响.方法 分离、培养hUCMSCs和大鼠AASCs.通过IMPACTOR MODEL-Ⅱ型打击仪将80只Wistar成年雌性大鼠均制作成T10损伤模型,随机分为四组(n=20):DMEM移植对照组、hUCMSCs移植组、AASCs移植组、hUCMSCs与AASCs联合移植组.比较符组动物恢复情况,进行行为学评分(BBB评分),NF-200和GFAP染色观察细胞存活、分化情况,生物素葡聚糖胺示踪观察皮质脊髓束再生情况.结果 4周后各组间BBB评分差异有统计学意义(P<0.05),6周后联合移植组明显高于其他三组,差异有统计学意义(P<0.05).免疫组化染色示联合移植组的hUCMSCs存活数量,NF-200、GFAP阳性荧光面积均明显高于hUCMSCs移植组,差异有统计学意义(P<0.05),BDA顺行爪踪可见联合移植组于损伤区染色较多,部分纤维延续至损伤远端.结论 AASCs可支持移植的hUCMSCs在损伤部位存活并向神经方向分化,hUCMSCs与AASCs联合移植较二者单独移植能更有效地促进脊髓损伤后运动功能的恢复和轴突再生.     

人骨髓间充质干细胞诱导分化为汗腺样细胞过程中microRNA表达谱差异的分析

目的:利用微小RNA (microRNA)表达谱基因芯片检测新技术,寻找人骨髓间充质干细胞(MSCs)分化为汗腺样细胞(SGLCs)过程中的关键microRNAs及其介导的分子信号通路.方法:通过间接培养方法诱导MSCs分化为SGLCs后,利用microRNA基因芯片检测,分析MSCs诱导前后以及MSCs、SGLC与正常成人汗腺细胞(SGCs)之间microRNA差异表达谱,筛选出其中发生极其显著改变的microRNAs,通过microRNA靶点预测软件,进一步筛选出其中直接靶向与汗腺发育、干细胞分化相关基因的microRNAs及其靶基因.结果:microRNA表达谱的差异比对结果显示,SGLCs与MSCs相比,19个microRNAs上调,49个microRNAs下调;SGCs与MSCs相比,120个microRNAs上调,59个microRNAs下调.取SGLCs与MSCs差异表达谱和SGCs与MSCs差异表达谱的交集,发现37个microRNAs在以上两个差异表达谱中均出现,其中12个microRNAs上调,25个microRNAs下调,它们可直接靶向与汗腺发育和干细胞分化相关的CEA等多个细胞因子,并参与EDA/EDAR、NF-κB、Wnt、ERK等多个相关信号通路的调节.结论:通过生物信息学靶点分析,成功寻找到在MSCs分化为SGLCs的过程中,靶向汗腺发育和干细胞分化相关细胞因子和信号通路的关键microRNAs.     

脐带间充质干细胞旁分泌物质对暴发性肝衰竭大鼠肝功能及肝细胞增殖的影响

Objective To investigate the therapeutic effect of human umbilical cord mesenchymal stem cell-paracrine substance on fulminant hepatic failure (FHF) rat, and to study the effect on liver function and hepatocyte proliferation. Methods Mesenchymal stem cells(MSCs)were separated from human umbilical cord, and surface makers of cells were detected by flow cytometry. Human umbilical cord mesenchymal stem cells-conditioned medium(MSC-CM) was prepared. FHF rat model was induced by intraperitoneal injection of D-galactosamine and they were randomly diveded into three groups: MSC-CM group, NS group, PHGF group. 24 h later, 1 ml MSC-CM, 1 ml 0. 9% NaCl solution and lml PHGF solution was injected into the tail vein of MSC-CM, NS, and PHGF rats, respectively. In each group (n=8 per group), blood samples were collected at 12, 24, 36, and 60 h after treatment from inner canthus for analysis of blood ALT and TBIL levels. We used five rats per group for tissue collection after sacrifice at 36 h after treatment and 10 animals per group for survival analysis. PCNA immunohistochemical staining was used in the sections of liver tissue to detect hepatocyte proliferation. Results 24 h after treatment, the levels of ALT and TBIL in the MSC-CM and PHGF groups were lower than those in the NS group(P＜0. 05), but there was no significant difference between the MSC-CM and PHGF groups. There were more PCNA-positive hepatocytes in the MSC-CM and PHGF groups than in the NS group(P＜0.01), but there was no significant difference between MSC-CM and PHGF group. Survival analysis found that the survival rate of rats in the MSC-CM and PHGF groups was higher than that of rats in the NS group (P=0. 049), but there was no significant difference between the MSC-CM and PHGF group. Conclusions The paracrine substance of human umbilical cord mesenchymal stem cells can stimulate hepatocyte proliferation and improve liver function of FHF rats, potentially creating a new avenue for the treatment of FHF.