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.

在这项为期三年的研究中，我们开发了一个微拉伸测试仪来测量单个分离细胞的拉伸特性，并在拉伸过程中观察细胞内结构的变化。用玻璃微孔管（I.D. 3-15mm）吸入细胞的两端，涂有细胞粘合剂（细胞-TAK），并用电动操纵器（MMS-77，Shimadzu）移动一个移液器，以在显微镜（BX50WI，Olympus）下拉伸细胞。施加到细胞的力是通过另一个移液器的悬臂部分的挠度来测量的。为了获得其清晰的图像，在直立显微镜下使用浸入水目标观察到了细胞。为了使细胞操作更容易，固定了显微镜的阶段，并移动目标以调整焦点。通过Epplant方法（P6-7）获得的牛主动脉平滑肌细胞（BASM）和通过酶促分散法获得的大鼠主动脉平滑肌细胞（RASM）在37℃处的物理盐溶液中成功延伸，以获得其张力性能。在各种拉伸速率下的BASM的拉伸试验表明，细胞的初始弹性模量与超过4％/s的应变速率显着正相关。 BASM和RASM的弹性模量分别约为3 kPa和约12kPa，分别低于0.2-4％/s的应变速率。由于细胞制备方法的差异，BASM和RASM被认为分别显示出合成和收缩表型。收缩细胞含有比合成细胞更多的收缩蛋白。收缩细胞可能比细胞质更硬。因此，收缩细胞可能比合成细胞更硬。在演讲研究中，BASM和RASM的机械性能的差异可能是由于两个细胞样品的表型差异所致。