Biomechanics Research Today is a free monthly online journal that collates and summarizes the latest research about Biomechanics, including details on mechanics of living organisms, movement, locomotion, prosthetic limbs.

Seeing tissue as a 'phase of matter': exploring statistical mechanics for the cell.

Pietak A, Waldman SD

Department of Mechanical and Materials Engineering, Queen's University, Kingston, Ontario, Canada. alexis.pietak@gmail.com

The field of tissue engineering aims to produce living, biological constructs which possess the appropriate spatial ordering of cells and their extra cellular matrix products. The complexity of a single cell and its interactions in a large collective have made development of useful models to assist in tissue culture difficult, and consequentially most tissue culture endeavors are limited to trial and error approaches. Some cell types display a natural tendency to spontaneously self-assemble into large domains of parallel-oriented cells. In this work, we show that these cell culture systems can be studied in the context of continuous disorder-order phase transformations. We suggest that collective ordering of the cells is controlled by the amount of noise in the walk of the individual cells (directional persistence) because undifferentiated mesenchymal stem cells display a seven-times higher directional persistence than mature fibroblasts and have a 24-times larger final-oriented domain size, an observation that corresponds with collective ordering in self-propelled particle systems. The study of cell culture systems using analogies derived from statistical mechanics yields simple, practical models offering insight into how a long-range order can be obtained in tissue-engineered constructs, providing a new paradigm for managing operations with large collectives of living cells.

Published 1 April 2008 in Phys Biol, 5(1): 16007.
Full-text of this article is available online (may require subscription).

© 2005-2008 Biomechanics Research Today. All Rights Reserved.