Design Of Three-dimensional Dynamic Mechanical Stimulation Device For Single Cell

Osteoarthritis(OA)is the most common disease in articular cartilage and the most common case of cartilage degenerative joint disease.The pathogenesis of OA involves many factors,such as gene,sex,age,environment and so on,but its pathogenesis remains unclear.It is well known that biomechanical factors play an important role in joint health and OA degeneration.Growing evidence indicated that the changes of cell morphology and mechanical microenvironment caused by the abnormal metabolic activity of chondrocytes are important factors for OA.Therefore,studying the effect of cell shape and matrix mechanical microenvironment on the mechanical and biological behavior of chondrocytes has important implications for understanding the occurrence of OA lesions and cartilage growth and development.However,the experimental techniques and platforms that can be used to study the effects of single cell shape evolution on cell mechanics and biological behavior have not been reported.In this paper,a single cell dynamic mechanical stimulation device was made,and the effect of different microniches on intracellular calcium signaling of chondrocytes was studied by single cell 3D microniche.Finally,a dynamic 3D matrix shape stretching system was established.The main research contents include:(1)The cell dynamic strain stimulation system was designed.By summarizing the shortcomings of the existing stretching devices,the 3D dynamic mechanical stimulation system of single cell is designed and manufactured,and the consideration of the design of dynamic strain system is expounded.this paper describes in detail the design structure and working principle of the single cell three-dimensional dynamic mechanical stimulation device,and the device has an important potential applications in the study of cell mechanobiology and cell-instructive biomaterial designing.(2)The 3D microniche models was established.This part mainly considers the substrate membrane with three kinds of normal chondrocyte 3D microniches,clarifies the distribution law of single cell shape and the size of the three shape boundaries,puts forward two kinds of chondrocyte cluster microniches in the process of OA,and describes in detail the preparation process of 3D microniches,which provided an experimental basis for the three-dimensional morphological culture and research of single chondrocytes.(3)The effects of different 3D microniches on intracellular calcium signaling of chondrocytes were revealed.The effects of 3D microniches on the intensity,frequency and spatial distribution of calcium concussion in single chondrocytes were quantitatively characterized.A dynamic 3D microniches stretching system was established to realize the mechanical stimulation of continuous and dynamic changes of a single chondrocyte in the 3D microniches.It provides a research method for retrieving the dynamic changes of cell morphology in normal physiological and pathological environment.