人脂肪间充质干细胞来源外泌体对脓毒症小鼠肺血管内皮细胞损伤的影响及其机制

目的:探讨人脂肪间充质干细胞（ADSC）来源外泌体对脓毒症小鼠肺血管内皮细胞（PMVEC）损伤的影响及其机制。方法:采用实验研究方法。取空军军医大学第一附属医院收治的3例行腹部手术切除患者（均为女性,年龄10~25岁）遗弃的新鲜脂肪组织进行原代人ADSC的分离培养,于第5天采用倒置相差显微镜观察细胞形态。取第3代ADS...     

人脂肪干细胞分泌因子对HaCaT细胞的生物学作用

目的：分离培养脂肪干细胞（ADSCs）以探讨其分泌因子对HaCaT细胞的生物学作用.方法：从人腹部脂肪组织中分离并培养ADSCs3d后,ELISA法测定ADSCs分泌血管内皮生长因子（VEGF）,肝细胞生长因子（HGF）含量;收集ADSCs培养液（ADSC-CM）作用于HaCaT细胞株.采用MTT法测定HaCaT细胞的增殖;AnexinV/PI双染色法测定HaCaT细胞的凋亡情况;体外细胞划痕法测定其迁移能力.结果：培养获得ADSCs细胞3d后,培养液中VEGF、HGF含量分别为（287±47）,（577±85）ng/L.MTT实验30%ADSC-CM组、50%ADSC-CM组的A490nm值分别高于对照组,差异具有统计学意义（P〈0.05或P〈0.01）.实验组HaCaT细胞凋亡率明显低于对照组（P〈0.05）.与对照组相比较,实验组HaCaT细胞迁移距离36,48h时间点显著增大（P〈0.05或P〈0.01）.结论：ADSCs能分泌细胞因子且对HaCaT细胞具有促增殖、迁移和抑制凋亡作用.     

兔骨髓间充质干细胞体外分离培养及多向诱导分化

背景:间充质干细胞不仅自身免疫原性弱,还可以调节细胞免疫功能,减轻移植物排斥反应,在组织工程中具有良好的应用前景.但骨髓中间充质干细胞含量稀少,约占单个核细胞的十万分之一到百万分之一.目的:建立一种分离、培养扩增兔骨髓间充质干细胞的方法,观察体外培养骨髓间充质干细胞的生长特性,及其潜在的诱导分化能力.方法:采用灌流法获取兔胫骨骨髓,密度梯度离心法联合贴壁培养法体外纯化扩增,相差显微镜观察其形态学特点,MTT法测定绘制传代骨髓间充质干细胞生长曲线,经成骨诱导液(L-DMEN/F12,体积分数为10%胎牛血清,0.1 μmol/L地塞米松,200 μmol/L抗坏血酸,10 mmol/L β-甘油磷酸钠)、成脂诱导液(L-DMEN/F12,体积分数为10%胎牛血清,1 μmol/L地塞米松,200 μmol/L吲哚美辛,0.5 mmol/L IBMX,10 mg/L胰岛素)、成软骨诱导液(L-DMEN/F12,体积分数为10%胎牛血清,10 μg/L转化生长因子β1,0.1 μmol/L地塞米松,50 μmol/L抗坏血酸,6.25 mg/L胰岛素)体外诱导骨髓间充质干细胞向成骨细胞、脂肪细胞及软骨细胞分化,并分别经碱性磷酸酶染色、油红O染色和甲苯胺蓝染色法鉴定.结果与结论:通过密度梯度离心法联合贴壁培养法可在体外大量扩增、纯化骨髓间充质干细胞,所获细胞具有高度自我更新能力和多向分化潜能,原代及传代骨髓间充质干细胞为梭形.经成骨细胞诱导,细胞碱性磷酸酶染色阳性;经成脂肪细胞诱导,细胞内出现红色脂滴,经成软骨细胞诱导,甲苯胺蓝染色阳性.     

成人不同部位角质形成细胞的生物学特性比较

目的:观察成人不同部位角质形成细胞的生物学差异,探讨用来构建自体组织工程皮肤的最佳表皮细胞来源. 方法: 体外分离培养成年男性头皮、躯干、下肢及包皮来源的角质形成细胞,分别利用绘制细胞生长曲线、3H-胸腺嘧啶(3H-TdR)掺入、流式细胞仪检测等方法比较细胞在生长增殖、细胞周期及代谢等方面的生物学差异. 结果: 在细胞的生长增殖及DNA合成代谢方面,头皮与包皮来源的角质形成细胞之间无统计学差异(P>0.05),躯干与肢体来源的细胞之间亦无统计学差异(P>0.05),但前两者均高于后两者(P<0.05);细胞周期分析表明,头皮及包皮来源的角质形成细胞S期比例高于躯干及肢体组. 结论: 头皮及包皮组织来源的角质形成细胞可作为构建自体组织工程皮肤的表皮细胞来源.     

重度烧伤大鼠血清对巨噬细胞Notch1的激活及分泌功能的影响

目的研究重度烧伤大鼠血清刺激后巨噬细胞Notch1蛋白表达变化,及其细胞分泌因子白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)的水平变化。方法选取成年雄性SD大鼠24只,随机分为假伤组、烧伤24 h组和烧伤7 d组,每组8只。烧伤组SD大鼠造成约30%总体表面积(TBSA)Ⅲ度烧伤,分别于伤后24 h、7 d收集血清;假伤组大鼠用37℃水浴,水浴后24 h取其血清作为对照。用上述各组血清制成20%培养液,刺激小鼠源巨噬细胞系RAW264.7,分别于加入血清刺激后即刻和刺激4、8、12、24、48 h后收取细胞及其上清液。另外用含20%假伤血清+脂多糖(100 ng/m L)培养液刺激巨噬细胞,于相同时间点收样。Western Blot检测各时间点巨噬细胞中Notch1蛋白表达变化,酶联免疫吸咐试验检测刺激24 h后培养上清液中IL-6及TNF-α的含量变化。结果 (1)假伤组血清刺激后即刻和刺激4、8、12、24、48 h后,Notch1蛋白表达无明显变化;(2)烧伤24 h组血清刺激后,Notch1蛋白表达明显升高,并随时间延长而达高峰;(3)烧伤7 d组血清刺激后,Notch1蛋白表达无明显变化,与假伤组血清刺激结果类似;(4)假伤组血清+脂多糖混合刺激后,Notch1蛋白表达明显增加;(5)烧伤24 h组血清及假伤组血清+脂多糖,上清液中IL-6和TNF-α含量均明显高于假伤组血清及烧伤7 d组血清。结论烧伤血清刺激下的巨噬细胞Notch1信号被激活,IL-6及TNF-α分泌能力增强,且这种激活可被脂多糖刺激所模拟。     

热损伤角质形成细胞培养上清对真皮成纤维细胞增殖与胶原mRNA表达的影响

目的 观察热损(创)伤后角质形成细胞(KC)培养上清对真皮成纤维细胞(Fb)增殖与胶原mRNA表达的影响.方法 建立KC热损伤模型,收集正常及热损伤12 h后培养上清配制不同浓度的细胞条件培养液;分离培养人正常Fb,实验组分别加入含不同浓度的细胞条件培养液,以单纯DMEM组为对照,采用噻唑蓝(MTT)比色法测定24 h后真皮成纤维细胞增殖;分别以流式细胞仪、实时荧光定量聚合酶链反应(Real-time PCR)测定DMEM组、50%浓度条件培养液组相同时间Fb生长周期及Ⅰ型胶原mRNA表达.结果 细胞增殖测定:热损伤上清(10%、30%、50%、70%)条件培养液组A值(0.151±0.004、0.165±0.009、0.195±0.006、0.202±0.008)均高于正常上清(10%、30%、50%、70%)条件培养液组(0.144±0.004,0.159±0.002,0.180±0.005,0.181±0.006)及对照组(0.144±0.007),除10%浓度组外各实验组A值与对照组比较差异均有统计学意义(t值分别为:4.01、11.42、11.41;P＜0.05),热损伤上清与正常上清条件培养液组比较:50%、70%浓度组间差异有统计学意义(t值分别为:2.03、1.94;P＜0.05);热损伤上清条件培养液50%与70%浓度组间差异无统计学意义(t值为1.34;P＞0.05).细胞周期测定见50%浓度热损伤上清组可明显促进Fb通过G1/S及S/G2限制点,S期及G2/M期细胞与对照组比较增多,G0/G1期细胞与对照组比较明显减少(t值分别为:5.87、11.3、4.86;P＜0.05).Ⅰ型胶原mRNA表达测定中,50%浓度热损伤上清组与对照组比较表达明显上调,差异亦有统计学意义(t=1.72;P＜0.05).结论 热损(创)伤后KC上清液可促进Fb的增殖,同时可上调Ⅰ型胶原mRNA的表达.

Abstract：

Objective To observe the effects of heat injured keratinocyte (KC) supematant on proliferation activity and collagen mRNA expression of the normal fibroblast (Fb).Methods A model of heat injured KC in vitro was reproduced,the supernatants of heat injured KC were collected and used as conditioned medium,and DMEM was used as control medium.Normal Fb were treated with different concentrations of conditioned medium.After treatment for 24 h,the proliferation activity,cell cycle and collagen Ⅰ mRNA levels in treated Fb were measured by using methylthiazol tetrazolium ( MTT),flow cytometry (FCM) and real-time polymerase chain reaction (PCR) techniques.Results As compared with the control group,the absorbance (A) values of MTT in treated groups were significantly increased (t = 4.01,11.42,11.41 ;P ＜0.05),except in 10% group (t = 1.34,P ＞0.05).As compared with normal supernatant treated group (0.159 ± 0.002,0.180 ± 0.005,0.181 ± 0.006),the A values in 50% and 70% conditioned medium group (0.195 ± 0.006,0.202 ± 0.008 ) were significantly increased ( t = 2.03,1.94;P ＜0.05).The 50% conditioned medium increased the percentage of G1 to S and S to G2 phase transit.As compared with control group,the number of cells in S and G2/M phase was increased significantly (t =5.87,11.3;P＜0.05 ) and that in G0/G1 phase decreased significantly ( t = 4.86;P＜0.05 ).Real-time PCR revealed that the collagen Ⅰ mRNA level in 50% conditioned medium group was significantly up-regulated (t= 1.72;P＜0.05 ) as compared with control group.Conclusion Heat injured KC supernatant may promote the proliferation of dermal Fb,and up-regulate the mRNA expression of collagen.     

ADSCs培养上清液对成纤维细胞的生物学影响

目的:分离培养脂肪干细胞(adipose-derived stem cells,ADSCs),探讨其培养上清液对成纤维细胞的生物学作用。方法:从人腹部脂肪组织中分离、培养ADSCs,收集其上清液培养人成纤维细胞。MTT法测定成纤维细胞的增殖;AnexinⅤ/PI双染色法测定成纤维细胞的凋亡;体外细胞划痕法测定其迁移能力。结果:培养获得ADSCs,ADSCs培养上清液实验组成纤维细胞的增殖及迁移均明显大于对照组(P<0.05或P<0.01);同时其凋亡率也低于对照组(P<0.05)。结论:ADSCs培养上清液能促进成纤维细胞的增殖、迁移及抑制凋亡发生。     

激活Hacat细胞表面Toll样受体促进创面愈合的机制

目的:细胞表面Toll样受体对激发先天性免疫、抵抗微生物感染有重要作用.最近研究发现激活细胞表面Toll样受体不仅可以预防微生物感染,还可以促进组织再生.实验通过脂多糖激活体外培养的角质细胞株Hacat细胞表面Toll样受体,观察其促进创面愈合的可能机制.方法:实验于2007-07在解放军第四军医大学西京医院烧伤与皮肤外科完成.①实验分组及方法:角质细胞株Hacat由解放军第四军医大学西京医院皮肤科馈赠;脂多糖为Sigma公司产品;小鼠抗人Toll样受体2单克隆抗体、兔抗人Toll样受体4多克隆抗体购于ebioscience公司.体外培养Hacat细胞,根据脂多糖(500 ng/L)与Hacat细胞共培养24,48,72 h将细胞随机分为脂多糖作用24 h 组、脂多糖作用48 h 组、脂多糖作用72 h 组,另设对照组,只加溶剂二甲基亚枫.②实验评估:蛋白免疫印迹技术检测脂多糖对Hacat细胞Toll样受体2、Toll样受体4及核因子-κB表达的影响;荧光定量聚合酶链反应检测脂多糖作用后Hacat细胞内基质金属蛋白酶3、基质金属蛋白酶9及血管内皮生长因子的表达.结果:光学显微镜下正常人皮肤表皮及角质细胞Toll样受体2、Toll样受体4表达呈蓝黑色;脂多糖作用于Hacat细胞24,48,72 h 后Toll样受体2、Toll样受体4、核因子-κB表达均高于对照组(P ＜ 0.01).与对照组相比,其他3组基质金属蛋白酶3及血管内皮生长因子表达均增高(P ＜ 0.01,P ＜ 0.05).脂多糖作用24 h 组基质金属蛋白酶9表达与对照组差异无显著性(P ＞ 0.05),脂多糖作用48,72 h 组与对照组比较,差异显著(P ＜ 0.05).结论:激活Hacat细胞表面Toll样受体有促进创面愈合作用,其机制可能与脂多糖作用于Toll样受体从而激活核因子-κB信号传导通路促进细胞释放基质金属蛋白酶3、基质金属蛋白酶9及血管内皮生长因子等因素有关.     

胰岛素对脂肪干细胞生长因子分泌功能的影响

Objective To study the effect of insulin in different concentrations on secretion function of growth factors of adipose-derived stem cells (ADSCs). Methods ADSCs were isolated from human ab-dominal adipose tissue and cultured. The immunophenotype and adipose induced-differenciation were identi-fied, and the third generation cells were collected. The collected cells were assigned to 1 × 10-8, 1 × 10-7, 1 × 10-6 mol/L insulin groups according to the concentration of added insulin. When cells grew into 70% confluence in conventional medium, ADSCs were cultured further in serum-free DMEM containing insulin in different concentrations for 3 days. ADSCs cultured in medium without insulin were used as control group. Secretion amount of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) of ADSCs were determined by enzyme-linked immunosorbent assay. The effects of the supernatant fluid of ADSCs' nutrient solution on the proliferation and collagen synthesis of the cultured fibroblast were detected by MTT chromatometry and hydroxyproline chromatometry. Results The secretion amounts of VEGF and HGF of ADSCs in 1 × 10-8 and 1 × 10-7 mol/L insulin groups [ (471±41, 762±66 ng/L), (643±64, 930±67 ng/L) , respectively ] were significantly higher as compared with those in control group (286±47, 577±84 ng/L) ( P <0.05 orP <0.01). No change occurred in the secretion amount of VEGF and HGF of ADSCs in 1±10-6 mol/L insulin group ( P >0.05 ). The supernatant fluid of ADSCs' nutrient medium of 1 ± 10-8 ,1 ± 10-7 mol/L insulin groups showed obvious stimulative effect on the proliferation and collagen synthesis of fibroblasts, and it was most obvious in the 1 ± 10-7 mol/L group ( P < 0.05 or P < 0. 01 ). Conclusions Insulin in the concentrations of 1 ± 10-8 and 1 ± 10-7 mol/L can notably promote ADSCs' function of secreting VEGF and HGF.