Study On Cell Mechanical Properties With A Homemade Platform

Cells can sense and respond to the stimulus in their microenvironment.Cell mechanosensation and mechanotransduction are involved in many cell processes,such as cell migration,cell differentiation,cell contact,etc.Cell mechanical properties are inherent properties of cells,which show the abilities of cells to deform and adhere.The mechanical properties of cells in various types are different from each other,because of the structure and shape.Even the cells are in the same type,the cell mechanical properties may be distinct under different microenvironment.To adapt the microenvironment,cells can change their mechanical properties by altering their cell structure,shape or signal pathways.Therefore,the study of cell mechanical properties can not only reveal the inherent properties of cells,but also reveal the response mechanisms of cells to different physiological and pathological conditions,which has important guiding significance for diagnosis and treatment,and drug study.The study of cell mechanical properties requires high-precision measurement methods at the nanometer and piconewton level.In this study,we designed and built a cell mechanical property measurement platform that can be used for quantitative research of various cell mechanical properties.Compared with the commonly used techniques for studying cell mechanical properties,such as micropipette technology,atomic force microscope,magnetic tweezers,optical tweezers and other technologies,the home-designed measurement platform in our research has strong adaptability,good scalability,large dynamic range and high precision.Based on this measurement platform,this study focused on the mechanical properties of cardiomyocytes,including Young's modulus of cardiomyocytes and integrin-mediated cell adhesion.The main research contents of this article include:First,based on the principle of the optical lever,the measurement platform for cell mechanical properties is designed.The design and construction of the platform is completely homemade,which is flexible and easy to expand and transform.The features of this platform is the Dual-probe component.The Dual-probe Structure allows the platform to save time during experiments and can be used to develop dual-probe applications,such as molecular crosstalk study.Then,we tested the reliability of the measurement platform from three aspects:magnification,minimum measurable displacement,and probe calibration.Further,we applied the measurement platform to measure Young's modulus of cardiomyocytes and compare the results with other studies.It is proved that the platform can realize the longitudinal displacement amplification at the nanometer level,and can detect the force at the piconewton level.Finally,the measurement platform was used to quantify the adhesion property of cardiomyocytes mediated by integrins.In this study,we explored the interaction between integrins and their different extracellular matrix protein ligands.We also examed the effect of metal cations on the integrin binding ability.This study found that,on one hand,the binding force of laminin to integrins on cardiomyocytes is the largest compared to collagen and fibronectin.On the other hand,different metal cations have different effects on integrin,where Ca2+ inhibit the integrins binding ability and Mg2+slightly enhance them.