Using Automated Cell Tracking Software to Quantifying Durokinesis and Durotaxis in Real Time

Abstract

In vivo, there is an intimate connection between certain cellular processes and the physical nature of the surrounding environment. Specifically, it has been theorized that changes in the physical properties of the extra-cellular environment within the vasculature influence cellular migration which can influence such processes as angiogenesis and occlusive vascular disease.In order to observe and quantify the compliance directed migration of both vascular smooth muscle cells and fibroblasts, we employed both polyacrylamide substrates, in which the tensile modulus could be tuned to specific values, and novel computer imaging software which automatically tracked cellular movement in less then ideal optical imaging conditions.Although both durotaxis and durokinesis have been previously observed in large population studies, our application of computer vision software allowed for a high throughput analysis of individual cells in real time. This method not only standardized the data collection but also enabled us to observe and quantify changes in speed, angular deviation, acceleration and deceleration within a single cell's migration track as a function of substrate stiffness and in the presences of a compliance gradient. This detailed analysis will serve to refine our understanding of cells respond to the physical stimuli presented in the environment.