Using Automated Cell Tracking Tools to Quantify Durokinesis and
Durotaxis in Real Time
 

Matthew L. Walker, David House, Margrit Betke, Joyce Y. Wong

Boston University, Boston, MA, USA



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 stiffness 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.