大鼠骨骼肌成肌细胞与乳鼠心肌细胞共培养对缝隙连接蛋白43表达的影响

目的 观察体外共培养的乳鼠心肌细胞与大鼠骨骼肌成肌细胞(简称L6细胞)以及乳鼠心肌细胞与转染外源性缝隙连接蛋白43(Cx43)基因的L6细胞(简称L6-Cx43细胞)间Cx43蛋白的表达情况,从而探讨共培养时心肌环境对成肌细胞的作用.方法 将乳鼠心肌细胞与4′,6-二脒基-2-苯基吲哚标记的大鼠骨骼肌成肌细胞进行共培养...     

CPUHY002对大鼠心肌细胞瞬时外向钾电流的影响

目的观察一种新合成的磷酸二酯酶Ⅲ(PDEⅢ)抑制剂CPUHY002对大鼠心肌细胞瞬时外向钾电流(Ito)的影响。方法采用全细胞膜片钳技术考察CPUHY002对急性分离大鼠心肌细胞和H9c2细胞系Ito的作用。结果在+50 mV下,CPUHY002对急性分离细胞和H9c2细胞系的Ito呈浓度依赖性抑制,其半数有效抑制浓度(IC50)分别为0.98μmol/L和0.91μmol/L;1μmol/L CPUHY002可使I-V曲线明显下移,Ito峰值分别下降(39.10±2.30)%和(47.32±2.06)%,激活曲线右移,失活曲线左移(未见于H9c2),恢复曲线无显著变化。结论 CPUHY002可浓度依赖性地抑制大鼠心肌细胞Ito。     

The role of shear stress on mechanically stimulated engineered vascular substitutes: influence on mechanical and biological properties

Vascular tissue engineering represents a promising field in the replacement of diseased vessels. The biological properties of three-dimensional (3D) collagen scaffolds indicate this material as a valid choice for vascular tissue engineering. Unfortunately, mechanical properties still remain unsatisfactory, due to a low burst pressure resistance and a plastic deformation. The use of a bioreactor to apply appropriate mechanical stresses have already shown a remodelling effect on the extracellular matrix and the behaviour of cells. In this study, we have shown the effect of the mechanical stress on elastin synthesis, which has a direct effect on the mechanical properties of the tissue-engineered vessel. We measured and compared the stress-strain curves, the elastic modulus and tenacity of a collagen tubular scaffold in the presence of C2C12 murine myoblasts cells, before and after the maturation in the bioreactor, applying a shear stress of 5 dynes/cm(2) for 3 days. Interesting evidence concerning the extracellular matrix structure, which significantly modify the biomechanical characteristics of the cellular scaffold, were observed, underlying the importance of focusing more effort in the research field of physiologically-guided 3D tissue-engineered substitutes.     

旋毛虫肌幼虫排泄分泌物激活的巨噬细胞和成肌细胞共培养对成肌细胞分化的影响

目的 体外研究与旋毛虫肌幼虫排泄分泌物(ML ES)作用后的巨噬细胞共培养对成肌细胞分化的影响,为深入了解旋毛虫包囊形成机理提供新的思路。方法 通过共培养技术对旋毛虫ML ES激活的巨噬细胞与成肌细胞进行共培养,建立J774A.1-C2C12细胞共培养模型。细胞免疫荧光法以及Western blot分析与旋毛虫ML ES处理的巨噬细胞共培养对成肌细胞分化以及成肌调节因子表达的影响。结果 细胞免疫荧光以及Western blot表明,与对照组比较,成肌细胞与ML ES作用后的巨噬细胞共培养明显降低成肌细胞分化调节因子(MyoD、Myogenin)阳性细胞的数量及终末分化标记物MHC的表达。结论 旋毛虫ML ES可以直接通过调节巨噬细胞活性来影响成肌细胞的分化,为研究旋毛虫与宿主细胞及旋毛虫感染后,宿主细胞间相互作用复杂机制提供了新的思路。     

重组纤溶酶原Kringle 5区基因杆状病毒载体的构建及表达研究

目的克隆人源性纤溶酶原Kringle5(K5)基因,构建K5分泌型杆状病毒载体,并检测其在肌细胞中的表达。方法引物中加入前胰岛素原信号肽基因序列,PCR产物经Age Ⅰ和Acc Ⅰ双酶切后装入pFB载体中构建为pFBK5,将其转染肌细胞C2C12,经Western印迹检测重组蛋白的表达并用MTT试验进行初步活性鉴定。结果成功扩增出了K5基因序列,测序正确,转染了pFBK5的C2C12细胞及上清中均检测到了特异性的14 ku蛋白条带且其对ECV304细胞产生剂量依赖性抑制作用,而转染空载体对照组无相应蛋白表达。结论人源性纤溶酶原K5分泌型杆状病毒载体构建成功,表达的重组蛋白具有生物活性,为进一步的病毒制备奠定了基础。     

犬成年骨骼肌成肌细胞的培养纯化、鉴定及生长特性的研究

目的建立简便、有效的成年犬骨骼肌成肌细胞（skeletal myoblast cells，SMCS）体外分离培养、纯化和鉴定的方法，并观察犬SMCs的生长特性。方法采用机械分解法与IA型胶原酶和胰蛋白酶的二步酶消化法相结合，分离消化法培养获取犬SMCs，用DMEM培养液培养，以Ficoll梯度液纯化，进行Desmin免疫组化鉴定，并观察细胞形态、生长特性。结果犬SMCs培养后经台盼蓝检查成活率达95％以上，在接种后4～5d增殖达高峰，细胞生长旺盛；Fiooll分离纯化的SMCs纯度较高；Desmin免疫细胞化学染色有97％的SMCs胞浆呈阳性反应。结论改良方法获得的SMCs具有良好的增殖、分化能力；采用FicollU纯化以血清培养，即可获得高产量高纯度的SMCs。     

周期性牵张应力下成肌细胞面积、周长的变化研究

目的基于成熟的细胞力学加载和细胞图像处理、分析方法,从细胞层次上定量观察成肌细胞周期性牵张应力加载后的面积、周长的时间改建效应。方法通过4点加力装置给成肌细胞施与各种时间段的生理性牵张应力(0.1Hz,2000μstrain),在相差显微镜下观察并记录细胞形态变化;借助计算机细胞图像处理和分析系统对成肌细胞形态进行定量分析。结果加力组和对照组的成肌细胞面积、周长测量值在加力0.5、1.0、2.0h后,两者差异不大,加力4h后两者的差异开始出现,加力8h后两者的差异变得明显;随着加力时间的延长,加力组和对照组间细胞形态参数测量的差别越来越明显。而去除细胞力学刺激后,成肌细胞形态都出现回复趋势。结论连续加力时细胞形态面积、周长变化明显,而停止加力后细胞面积、周长有回复的趋势。     

Promotion of muscle regeneration by myoblast transplantation combined with the controlled and sustained release of bFGFcpr

Although myoblast transplantation is an attractive method for muscle regeneration, its efficiency remains limited. The efficacy of myoblast transplantation in combination with the controlled and sustained delivery of basic fibroblast growth factor (bFGF) was investigated. Defects of thigh muscle in Sprague–Dawley (SD) rats were created, and GFP‐positive myoblasts were subsequently transplanted. The rats were divided into three groups. In control group 1 (C1) only myoblasts were transplanted, while in control group 2 (C2) myoblasts were introduced along with empty gelatin hydrogel microspheres. In the experimental group (Ex), myoblasts were transplanted along with bFGF incorporated into gelatin hydrogel microspheres. Four weeks after transplantation, GFP‐positive myoblasts were found to be integrated into the recipient muscle and to contribute to muscle fibre regeneration in all groups. A significantly higher expression level of GFP in the Ex group demonstrated that the survival rate of transplanted myoblasts in Ex was remarkably improved compared with that in C1 and C2. Furthermore, myofibre regeneration, characterized by centralization of the nuclei, was markedly accelerated in Ex. The expression level of CD31 in Ex was higher than that in both C1 and C2, but the differences were not statistically significant. A significantly higher expression level of Myogenin and a lower expression level of MyoD1 were both observed in Ex after 4 weeks, suggesting the promotion of differentiation to myotubes. Our findings suggest that the controlled and sustained release of bFGF from gelatin hydrogel microspheres improves the survival rate of transplanted myoblasts and promotes muscle regeneration by facilitating myogenesis rather than angiogenesis. Copyright © 2013 John Wiley & Sons, Ltd.     

connexin43基因体外转染大鼠L6骨骼肌成肌细胞的研究

目的将含有connexin43基因的质粒在脂质体的介导下转染进入大鼠L6骨骼肌成肌细胞,使用G418根据有限稀释法筛选单克隆细胞株L6 myoblast-Cx43。方法通过免疫细胞化学技术、Western blot技术,对整合有connexin43基因的阳性细胞克隆进行检测。结果两个阳性克隆组Cx43蛋白表达均明显高于对照组。结论获得的两个持续高表达connexin43蛋白的细胞株可用于进行移植细胞之间及移植细胞与宿主细胞之间能否形成良好的电偶联的研究。