权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of a micro tensile tester for the in-process monitoring of cell structure

开发用于过程中监测细胞结构的微型拉伸测试仪

基本信息

批准号：
09558109
负责人：
MATSUMOTO Takeo
金额：
$ 3.58万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

In this 3-year study, we have developed a micro tensile tester to measure tensile properties of a single isolated cell and to observe change in intracellular structure during stretching simultaneously. Both ends of the cell were aspirated with glass micropipettes (3-15mm in I.D.) coated with cellular adhesive (Cell-Tak), and one pipette was moved with an electrical manipulator (MMS-77, Shimadzu) to stretch the cell under a microscope (BX50WI, Olympus). The force applied to the cell was measured by the deflection of a cantilever part of the other pipette. To obtain its clear image, the cell was observed with water immersion objectives under the upright microscope. To make cell manipulation easier, the stage of the microscope was fixed and the objectives were moved to adjust the focus. Bovine aortic smooth muscle cells (BASMs) obtained by the explant method (P6-7) and rat aortic smooth muscle cells (RASMs) obtained by the enzymatic dispersion method were successfully stretched with the tester under a physiological salt solution at 37℃ to obtain their tensile properties. Tensile tests of BASMs at various stretch rate show that initial elastic modulus of the cell have a significant positive correlation with the strain rate over 4 %/s. Elastic modulus of BASMs and RASMs were about 3 kPa and about 12kPa, respectively under the strain rate of 0.2-4 %/s. Due to the difference in the cell preparation method, BASMs and RASMs are considered to show synthetic and contractile phenotype, respectively. Contractile cells contain much more contractile proteins than synthetic cells. Contractile proteins may be stiffer than cytoplasm. Contractile cells may thus be stiffer than synthetic cells. The difference in the mechanical properties of BASMs and RASMs in the present study may be due to the difference in the phenotype of the two cell specimens.

在这项为期3年的研究中，我们开发了一种微型拉伸测试仪，用于测量单个分离细胞的拉伸性能，并同时观察拉伸过程中细胞内结构的变化。细胞两端用玻璃微吸管吸气(内径3~15 mm)。细胞粘附剂(Cell-Tak)包被，一根吸管用电动机械手(MMS-77，岛津)移动，在显微镜(BX50WI，奥林巴斯)下拉伸细胞。施加在电池上的力是通过另一根吸管的悬臂部分的偏转来测量的。为了获得其清晰的图像，在直立显微镜下用水浸物镜观察细胞。为了使细胞操作更容易，显微镜的工作台被固定，物镜被移动以调整焦距。用该试验机在37℃的生理盐溶液中成功地拉伸了组织块法获得的牛主动脉平滑肌细胞(BASM)(P6-7)和酶分散法获得的大鼠主动脉平滑肌细胞(RASM)。不同拉伸速率下的拉伸实验表明，细胞的初始弹性模数与应变率在4%/S以上呈显著正相关，在0.2-4%/S的应变率下，BASM和RASM的弹性模数分别约为3kPa和12kPa.由于细胞制备方法的不同，BASM和RASM分别表现为合成和收缩表型.收缩细胞比合成细胞含有更多的收缩蛋白。收缩蛋白可能比细胞质更硬。因此，收缩细胞可能比合成细胞更硬。本研究中BASM和RASM力学性能的差异可能是由于两种细胞标本的表型不同所致。