| Summary: | 碩士 === 國立嘉義大學 === 生物機電工程學系研究所 === 101 === In this study, the mice adipocytes precursor cells (3T3-L1) were cultured on PDMS which are fabricated with two propotions of master agent to curing agent are 7:1 and 14:1. It made two different hardness PDMS which offered to culture cell. In order to stimulate cells growth by mechanical stretch force in vitro culture, a programmable control system of vertical stretch mechanical force is developed to simulate cells growth in this study.Then measured cell adhesion force by DEP force. This vertical force stimulation system can be set-up strain, frequency, stretch time and mode (continuous or intermittent). and controlled at 37 ° C and 5% CO2 environment in order to simulate the human cells in vivo. The experiment cultured cell on different hardness substrates and different cultured time. Then the cell growth is observed under vertical stress stimulation with different stretch strain. It compared the relationship between the cell adhesion force and different stretch strain and investigated the integrin gene expression.
The PDMS surface properties were measured with the contact angle, AFM and force-displacement analysis, it obtained the results known as a hard substrate 7:1 and 14:1 for the soft substrate. The cell morphology will be changed before and after under stress stretch. The direction of adipocytes growth under stress stretch stimulation presented perpendicular to the direction of stress.
Both hard and soft substrates are hydrophobic materials which are no significant difference. The surface roughness of hard base (7:1) is larger than that of soft base material (14:1), but the roughness does not affect cell adhesion. The adhesion force under different stretch strain (5%, 10%, 15%) stimulation has shown the cell adhesion strength of 15%> 10%> 5%> 0% (no stress). It found the relationship between cell adhesion force and stretch strain is positive. If cell encountered too much stretch strain, may cause cell death or poor adhesion. The integrin gene expressions are obtained with a quantitative real-time polymerase chain reaction (Q-PCR). It found the relationship between gene expression of integrin α1 and cell adhesion force is positive. But there is no tendency for others integrins. The experimental result shows the gene expressions of integrin α1 will be regulated by the different vertical stretch stress.
|
|---|
