(446c) Mammary Epithelial Cells Exhibit A Bimodal Correlated Random Walk Pattern

Cellular tracks of MCF-10A pBabe, neuN and neuT random migration on 2-D plastic substrates, analyzed using bimodal analysis(2), were found to reveal a bimodal correlated random walk. We find two types of exponentially distributed correlated flights (corresponding to what we refer to as the directional and re-orientation phases). These flights each have a specific form of turn angle distribution representing the correlation between move step-lengths within flights. We analyzed these flights using different methods (logarithmic binning with normalization(3) and survival frequency(1) plots) to determine the presence of any Lévy modulation in the flights instead of exponential model. We did not find any strong evidence of a power-law behavior in the flight lengths as revealed by the survival frequency distributions. Since the presence of non-uniform turn angle distribution of move-step lengths within a flight and two different types of flights were found, we propose that the epithelial random walk is a bimodal correlated random walk (BCRW) comprising of two alternating modes with varying degree of correlations, rather than a simple correlated random walk. A BCRW model (as opposed to a simple correlated random walk) correctly matches the super-diffusivity in the cell migration paths in the absence of any biasing cues (haptotaxis or chemotaxis) as indicated by simulations based on the BCRW model.

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2.Potdar, A. A., J. Lu, J. Jeon, A. M. Weaver, and P. T. Cummings. Bimodal analysis of mammary epithelial cell migration in two dimensions. Ann. Biomed. Eng. 37: 230-245, 2009.

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