Substrate stiffness affects the response and phenotype of inflammatory cells in vivo

The interaction of cells with their environment is guided both by biochemical and physical forces. The effects of these physical forces on cellular function is termed mechanosensing. Recent studies in mechanosensing using polyacrylamide gels of different stiffnesses to approximate various tissues in the body have shown that inflammatory cells respond differently to substrates of varying stiffness. In vitro experiments show that neutrophils have greater adhesion and more persistent migration on gels of higher stiffness. Previous studies of in vivo wound healing involved the implantation of polyvinylalcohol (PVA) sponges into mice. The sponges were recovered after varying amounts of time to characterize the responding inflammatory cells. Using the PVA sponge protocol as a guide, our goal is to implant gels of different siffnesses (10 and 100kPa) into mice in order to study the differences in the inflammatory response on these substrates. The attached cells will be extracted from the gels, counted, and phenotyped. We expect to find that the inflammatory cells will have variation in their immunoidentity based on the stiffness of the gel substrates.