改良组织块贴壁法制备人脐带间充质干细胞

目的采用改良组织块贴壁法制备人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,hUCMSCs)。方法无菌条件下取足月婴儿脐带,采用改良组织块贴壁法分离间充质干细胞,台盼蓝染色法计数单个核细胞数,倒置相差显微镜下观察细胞形态,流式细胞仪检测细胞周期及免疫表型。结果原代hUCMSCs的数量为(1~5)×105个。培养至8 d,组织块边缘处有单细胞爬出;培养至2周,贴壁生长的细胞散在分布或形成小克隆;培养至20 d,细胞呈梭型、三角形或多角形。培养第20天的原代hUCMSCs的G0/G1期细胞占88.12%,S期细胞占1.23%,G2/M期细胞占10.65%,大多数细胞处于细胞增殖的潜伏期,CD105阳性率为97.65%,CD34阳性率为2.54%。结论采用改良组织块贴壁法分离了hUCMSCs,其生物学特性与骨髓间充质干细胞相似,为其临床应用奠定了基础。     

血小板裂解液大规模扩增人脐带间充质干细胞

目的用血小板裂解液(platelet lysate,PL)大规模扩增人脐带间充质干细胞(umbilical cord mesenchymal stem cell,UCMSC),并检测其生物学特性,为临床应用提供实验依据。方法分别采用PL和胎牛血清(FBS)低密度扩增人UCMSC,比较两组UCMSC的细胞形态、大小、克隆形成率、增殖能力、细胞表型和分化能力。结果 PL扩增的UCMSC形态细长;直径明显小于FBS扩增的UCMSC(P<0.05);克隆形成率与FBS扩增的UCMSC差异无统计学意义(P>0.05);有更高的细胞累积群倍数;与FBS扩增的UCMSC有相似的细胞表型;与FBS扩增的UCMSC均具有成骨、成脂诱导分化能力,但PL扩增的UCMSC成骨分化能力更强。结论 PL可取代FBS用于大规模扩增UCMSC。     

二次贴壁法高效制备人脐带间充质干细胞

目的采用二次贴壁法高效制备人脐带间充质干细胞(human umbilical cord derived mesenchymal stem cells,hUC-MSCs)。方法将传统组织块贴壁法弃掉的脐带组织块转移至新的培养瓶中进行二次贴壁,分离hUC-MSCs,并用无血清培养体系连续传代,镜下观察细胞形态;分别检测不同代次细胞的增殖能力、细胞周期、免疫表型、多向分化能力。结果二次贴壁法分离的hUC-MSCs在第4天即出现细胞克隆,第8天汇合度可达70%,经过二次贴壁法,1根20 cm的脐带组织共获得P3间充质干细胞(MSCs)总数为1×10~9个。二次贴壁分离的细胞增殖能力旺盛,与一次贴壁获得的干细胞同代次平均倍增时间差异无统计学意义(P0.05)。传统贴壁法与二次贴壁分离的细胞均表达超过98%的CD73、CD90、CD105和低于2%的CD34、CD45、CD14、CD79a、HLA-DR,且该细胞具有分化为成骨、成软骨和成脂能力。结论经无动物源培养体系体外扩增的二次贴壁分离方法可以获得大量具有MSCs生物学特性的hUC-MSCs,为其规模化临床应用奠定了基础。     

一种分离培养人脐带Wharton's jelly间充质干细胞的新方法

目的探讨一种分离培养人脐带Wharton′s jelly间充质干细胞(mesenchymal stem cell,MSC)的新方法。方法取人脐带组织,除去动静脉后剪碎成2～5 mm3,将组织碎片浸入4 g/LⅠ型胶原酶和1 g/L透明质酸酶的混合液中,于37℃处理1 h,再用0.25%胰蛋白酶在相同条件下消化30 min,得到的消化液经70μm细胞滤网过滤后,制备单个细胞悬液,培养并传代。取P1、P3、P7代脐带Wharton′s jelly MSC,绘制细胞生长曲线;取P3代细胞,采用流式细胞术检测细胞表面标记分子,并分别采用成骨和成脂诱导培养基进行成骨及成脂诱导分化,茜素红染色和油红O染色观察结果。结果 P1、P3代脐带Wharton′s jelly MSC的增殖能力强,且P1代细胞的增殖能力强于P3代,P7代细胞的增殖能力较P3代细胞有所减弱。P3代脐带Wharton′s jelly MSC高表达CD90(99.8%)、CD105(100%)和CD166(100%),低表达CD45(0.3%)、CD14(0.1%)、CD34(0.2%)和CD79a(0.3%),不表达HLA-DR。P3代Wharton′s jellyMSC经成骨诱导后,茜素红染色可见红色结节;经成脂诱导后,油红O染色可见脂质沉积。结论本方法获得的Wharton′s jelly MSC活性好,增殖能力强,为后续实验研究及临床应用提供了理想的种子细胞。     

人脐带间充质干细胞来源工程化纳米囊泡的制备与鉴定

目的：探索来源于人脐带间充质干细胞（hUC-MSCs）的工程化纳米囊泡（Nanovesicle,NVs）的制备与鉴定方法,为深入了解工程化NVs的生物学功能提供数据基础。方法：采用物理方式破碎hUC-MSCs以获取NVs,并采用改良的超速离心法进行分离和纯化;通过纳米颗粒跟踪分析（NTA）、透射电镜（TEM）观察、蛋白质免疫印迹（WB）及生物学活性分析方法鉴定NVs的特性。结果：建立的方法成功分离出NVs,TEM下观察到NVs呈中间凹陷的茶杯样结构;NTA结果显示NVs直径在100 nm左右;Western Blot实验证实NVs几乎不表达外泌体特异性蛋白TSG101;生物学活性实验表明NVs不能促进人皮肤成纤维（HSF）细胞增殖。结论：本研究建立的hUC-MSCs来源的NVs提取及鉴定方法可行,为NVs在未来的临床研究提供了数据基础。     

干扰素γ对血小板裂解液扩增的人脐带间充质干细胞免疫调节功能的影响

目的探讨干扰素(interferonγ,IFNγ)对血小板裂解液扩增的人脐带间充质干细胞(umblical cord mesenchymal stem cells,UCMSCs)免疫调节功能的影响。方法采用血小板裂解液(platelet lysate,PL)扩增UCMSCs,通过细胞形态、细胞表型和分化能力检测IFNγ(10 ng/m L)对UCMSCs生物学特性的影响。同时采用ELISA法分析IFNγ对UCMSCs分泌免疫相关因子PGE-2、TGF-β1和IL-6的影响,CCK-8法检测IFNγ对UCMSCs抑制人外周血单个核细胞(peripheral blood mononuclear cells,PBMCs)增殖的影响。结果 IFNγ预处理对UCMSCs在细胞形态、细胞表型、细胞成骨和成脂肪的分化能力方面无明显影响(P0.05);IFNγ预处理可显著促进UCMSCs的TGF-β1及IL-6分泌(P0.05),但对PGE-2的分泌无明显影响(P0.05);IFNγ预处理可增强UCMSCs对PBMCs增殖的抑制作用(P0.05)。结论 IFNγ预处理可增强UCMSCs的免疫调节功能。     

人脐带华通氏胶间充质干细胞的生物学特性及其向肌源性细胞分化的能力

目的探讨人脐带华通氏胶间充质干细胞(human umbilical cord Wharton′s Jelly mesenchymal stem cells,hUCMSCs)的生物学特性及其向肌源性细胞分化的能力。方法收集健康足月产胎儿脐带组织,采用酶消化法从华通氏胶中分离hUCMSCs,选取第3代对数生长期细胞,显微镜观察细胞形态,流式细胞术检测细胞免疫表型分子的表达,免疫荧光染色检测干细胞标记物及其体外向肌源性细胞的分化,荧光显微镜观察及流式细胞术检测携带绿色荧光蛋白(green fluorescent protein,GFP)的慢病毒转染hUCMSCs后GFP的表达。结果采用酶消化法获得可贴壁生长的大量hUCMSCs,其能在体外成功进行扩增培养。hUCMSCs可高表达CD29、CD44、CD73、CD90和CD105,而极低表达CD14、CD34、CD45和HLA-Ⅱ;能表达干细胞标记物Oct4和Sox2,且在体外特殊培养条件下表达骨骼肌干细胞标记物Pax7和Myo D;转染的hUCMSCs可稳定表达GFP,转染率高达50%~70%。结论人脐带华通氏胶组织存在间充质干细胞,且其具有向肌源性细胞分化的潜能。     

大鼠骨髓间充质干细胞向肝样细胞的定向诱导分化

目的 探讨肝细胞生长因子(Hepatocyte growth factor,HGF)和碱性成纤维细胞生长因子(Basic fibroblast growthfactor,bFGF)诱导大鼠骨髓间充质干细胞(Bone marrow mesenchymal stem cells,BM-MSCs)分化为肝样细胞的可行性。方法取SD大鼠股骨骨髓,直接贴壁法分离纯化BM-MSCs,并体外传代,流式细胞术和成骨诱导对其进行鉴定。取第3代BM-MSCs,分为2组:实验组用HGF(20 ng/ml)和bFGF(10 ng/ml)进行诱导,阴性对照组不加诱导剂,倒置显微镜下观察细胞形态变化;RT-PCR法检测诱导后细胞甲胎蛋白(Alpha fetoprotein,AFP)和白蛋白(Albumin,ALB)基因mRNA的转录水平;免疫细胞化学染色法检测诱导后细胞的AFP和ALB蛋白的表达。结果第3代BM-MSCs表型标志和功能特性均符合MSCs的特点。BM-MSCs经HGF和bFGF诱导后呈肝样细胞形态。实验组细胞可检测出AFP和ALB基因mRNA的表达。实验组细胞诱导后第7天,AFP蛋白开始表达,第14天时表达降低,第21天时不表达;ALB于诱导后第14天出现表达,并随诱导时间的延长表达逐渐增加。结论 HGF和bFGF具有体外诱导BM-MSCs向肝样细胞分化的作用。     

脐带间充质干细胞长期体外培养的生物学特性及遗传稳定性

目的观察脐带间充质干细胞(umbilical cord mesenchymal stem cells,UC-MSCs)体外长期培养的生物学特性及遗传稳定性。方法从剖宫产足月健康新生儿脐带中分离培养UC-MSCs,并连续传代,显微镜下观察细胞形态。分别检测P3和P12代UC-MSCs的增殖能力、免疫表型、向成脂肪细胞和成骨细胞的分化诱导率、衰老情况、成纤维细胞集落形成单位(CFU-F)及染色体核型。结果 P3代UC-MSCs为形态相对均一的梭形贴壁细胞,呈平行排列生长或旋涡状生长;P12代UC-MSCs宽大扁平,贴壁性减退,漂浮细胞增多,胞浆内出现黑色颗粒和空泡;P3和P12代UCMSCs均表达CD73、CD90、CD105,不表达CD34、CD45、HLA-DR;P3较P12代UC-MSCs的细胞增殖能力及向成脂肪细胞分化诱导率均明显升高(P均0.05);向成骨细胞分化诱导率及细胞衰老率均明显降低(P均0.05);成纤维细胞集落数及染色体中期分裂相明显增多(P0.05)。结论长期体外培养的UC-MSCs生物学特性发生改变,遗传学特性稳定,但染色体中期分裂相减少。     

骨髓间充质干细胞对大鼠胰腺损伤组织的修复作用

目的观察骨髓间充质干细胞(MSCs)对大鼠胰腺损伤组织的修复作用。方法应用贴壁法分离、纯化、扩增大鼠MSCs,经流式细胞仪检测其细胞周期及表面标志后,用DAPI标记,经尾静脉注入胰腺损伤模型大鼠体内,15d后,在激光共聚焦显微镜下观察MSCs在大鼠胰腺组织的定位,组织病理切片观察胰腺损伤组织的病理改变,PCR检测胰腺损伤区组织的Sry基因。结果体外纯化、扩增、富集的MSCs经流式细胞仪检测,86.67%的细胞处于G0/G1期,细胞表面CD34呈阴性表达,CD44呈阳性表达。DAPI标记的MSCs移植治疗15d后,激光共聚焦显微镜下可见,MSCs在损伤的胰腺组织中多见,在正常胰腺组织中偶见;组织病理切片可见损伤的胰腺组织结构开始恢复,胰岛再建;PCR结果显示,治疗组胰腺组织可扩增出Sry基因。结论MSCs对大鼠胰腺损伤组织可能具有修复作用。     

Platelet lysate and adipose mesenchymal stromal cells on silk fibroin nonwoven mats for wound healing

In this work platelet lysate (PL) and adipose‐derived mesenchymal stromal cells (ASCs) seeded on nonwoven fibroin mats were in vitro and in vivo evaluated for tissue regenerative applications. Nonwoven mats obtained by a large scale water entanglement technique were characterized for their physico‐chemical properties. Results indicated a high purity of fibroin fibers, their stability after sterilization process and appropriate technological properties suitable for tissue engineering. Moreover, the scaffolds in vitro supported adhesion and migration of ASCs and the presence of PL improved the cell proliferation. The products were then applied on epithelial/dermal wounds carried out on the dorsal surface of rabbit: the skin reparative process was solved in 9 days, with a completely restitutio ad integrum of the epithelium in animals treated with PL alone; ASCs did not further improve the wound healing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42942.     

PVA hydrogels loaded with a Brazilian propolis for burn wound healing applications

PVA hydrogels offer many suitable characteristics for burn wound dressings. However, unmodified PVA gels do not act against infection. Propolis is a natural antimicrobial agent suitable for incorporation into PVA gels. PVA–propolis gels were produced by freeze–thawing method, and their microstructure, mechanical, and swelling properties (in standard PBS and a PBS‐based solution with pH 4.0) were characterized. The propolis release profiles and the gel's antibacterial and cytotoxicity properties were also investigated. The presence of propolis in the gels interfered with the PVA crystallization profile and with the mechanical properties. All samples swelled at least 400% in both media. The propolis was mostly released to the media in the first day of immersion. PVA–propolis gels with concentrations of 15% propolis or more were active against the gram‐positive bacterium Staphylococcus aureus, which is associated with initial colonization of the wound. All PVA–propolis samples acted as barriers to microbial penetration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42129.     

人胎盘来源的造血干细胞和间充质干细胞的分离及鉴定

目的建立人胎盘来源的造血干细胞(placenta hematopoietic stem cells,hP-HSCs)和间充质干细胞(placentaderived mesenchymal stem cells,hP-MSCs)的分离方法,并进行鉴定和组分分析。方法选取10份新生健康婴儿胎盘组织,采用机械破碎法联合磁珠分选法分离h P-HSCs,胎盘绒毛膜组织块贴壁法分离hP-MSCs,利用形态学观察、集落培养、流式细胞术等进行鉴定。结果 hP-HSCs:分离后有核细胞数(total nucleated cell number,TNC)为(11. 82±2. 46)×10~8个,TNC回收率≥80%;细胞活性为(99. 7±0. 3)%;细胞表面抗体CD34~+CD45dim表达率为(8. 69±0. 36)%,CD34~+总数为(108. 0±6. 48)×10~6个;集落形成总数为(1. 88±1. 07)×10~6。hP-MSCs:冻存细胞总数为(40. 78±9. 35)×10~7个;细胞活性为(99. 0±1. 5)%;细胞表面抗体CD34~+CD45~+表达率为(0. 1±0. 1)%,CD44~+CD105~+为(99. 6±0. 2)%,CD14~+CD19~+为(0. 1±0. 1)%,CD90~+CD73+为(98. 9±0. 2)%;且具有良好成脂、成骨分化潜能。结论成功建立了hP-HSCs和hP-MSCs体外分离培养方法,为胎盘的临床应用奠定了基础,并提供了细胞种子资源。     

Genotoxicity of graphene nanoribbons in human mesenchymal stem cells

Single-layer reduced graphene oxide nanoribbons (rGONRs) were obtained through an oxidative unzipping of multi-walled carbon nanotubes and a subsequent deoxygenation by hydrazine and bovine serum albumin. Human mesenchymal stem cells (hMSCs) were isolated from umbilical cord blood and used for checking the concentration- and time-dependent cyto- and geno-toxic effects of the rGONRs and reduced graphene oxide sheets (rGOSs). The cell viability assay indicated significant cytotoxic effects of 10 μg/mL rGONRs after 1 h exposure time, while the rGOSs exhibited the same cytotoxicity at concentration of 100 μg/mL after 96 h. The oxidative stress was found as the main mechanism involved in the cytotoxicity of the rGOSs which induced a slight cell membrane damage, while RNA efflux of the hMSCs indicated that neither generation of reactive oxygen species nor the significant membrane damage of the cells could explain the cell destructions induced by the rGONRs. Our results demonstrated that, the rGONRs could penetrate into the cells and cause DNA fragmentations as well as chromosomal aberrations, even at low concentration of 1.0 μg/mL after short exposure time of 1 h.     

高浓度葡萄糖和亮氨酸联合作用对人脐带血间质干细胞增殖和凋亡的影响

目的探讨高浓度葡萄糖和亮氨酸联合作用对人脐带血间质干细胞(human cord blood-derived mesenchymal stem cells,hUCB-MSCs)增殖和凋亡的影响。方法贴壁培养法分离、纯化并传代培养hUCB-MSCs,采用流式细胞术检测第3代hUCB-MSCs表面抗原CD29、CD34和CD44的表达;将hUCB-MSCs分为葡萄糖组、亮氨酸组和联合刺激组,葡萄糖液和亮氨酸液终浓度分别为28和1.35 mmol/L,并设PBS对照组。37℃培养3 d后,采用MTT法检测细胞的增殖活力;流式细胞术Annexin-V/PI染色法检测细胞的凋亡情况;Western blot法检测细胞凋亡相关蛋白Bcl-2和Bax的表达。结果 hUCB-MSCs呈CD29+CD44+CD34-。药物处理3 d后,与PBS对照组相比,葡萄糖组和亮氨酸组hUCB-MSCs的增殖活力、凋亡率、Bcl-2和Bax蛋白的表达水平均无明显变化(P>0.05);而联合刺激组hUCB-MSCs的增殖活力受到明显抑制,凋亡率显著升高,Bcl-2蛋白的表达水平明显降低,Bax蛋白的表达水平明显升高(P<0.01)。结论高浓度葡萄糖和亮氨酸联合作用可抑制hUCB-MSCs增殖,促进其凋亡。本研究在一定程度上为干细胞治疗糖尿病提供了实验依据。