Development of an experimental device for the application of static and dynamic tensile strain on cells

The aim of this work was the development of new devices for the application of tensile strain on cells. A basic system was intended to stretch cells with physiological static forces. However, as biological systems are dynamic, a second device was built as an automatic dynamic apparatus. To establish a standardized process, commercial BioFlex (R) plates (Flexcell International, NC, USA) were integrated as cell adhesion membranes. In preliminary studies the mechanical behavior of these cell plate membranes was analyzed. In both systems the membranes were pulled over cylindrical stamps to get evenly distributed strains. The construction of the static system predominantly consisted of polyoxymethylene (POM), the dynamic system was reinforced with aluminum. The dynamic setup was equipped with a high-resolution linear translation stage and was computer-controlled with a program written in the LabView (TM) software. Various cell types were stressed with diverse strains over different time periods and first results have been published. Measurements of the 3% strained cell plate membrane and of there adnated cells resulted in cell elongations of 3.7%. The results demonstrated a high repeatability and the systems were regarded as being easy to use.