Vascular smooth muscle cell durotaxis depends on extracellular matrix composition

Many cell types have been observed to migrate toward stiffer regions of mechanical gradients in a process termed durotaxis. Tissue stiffness gradients are being discovered in an increasing number of diseases, including cancer and fibrotic diseases. However, the role of ECM composition, which often changes in diseased tissues with stiffness, in directing this behavior has not previously been investigated. To understand how stiffness gradients and changing matrix composition may affect cell migration in disease, we have designed a mechanical gradient platform that allows for independent control of absolute stiffness, gradient steepness, and ECM coating. We demonstrate that smooth muscle cells will undergo durotaxis on mechanical gradients coated with fibronectin but not laminin.