New Theory Describes How Physical Environment Influences Stem Cell Development

Physical factors may be as important as chemical signals in determining when and how stem cells differentiate into mature tissue cells.

Investigators at the Hebrew University of Jerusalem (Israel) and their collaborators at other institutions have developed a physical model, supported by data from biological growth experiments that demonstrates how the alignment of stress fibers within stem cells is a determinant for when and how the stem cell differentiates into a mature cell type.

They reported in the June 2010 issue of the journal Nature Physics that the cell, in essence, is an extension of the supporting medium. Thus, cells growing on a supporting matrix whose rigidity mimics that of muscle tissue become elongated and filled with aligned muscle-like fibers. In contrast, cells growing on a softer matrix that mimics brain tissue adopt more symmetric structures and differentiate into brain cells. Stem cells growing on a more rigid, bone-like matrix, adopt the characteristics of bone cells.

First author Dr. Assaf Zemel, professor of molecular dynamics at the Hebrew University of Jerusalem, said, "These findings shed new light on our understanding of the mechanisms that govern the differentiation of stem cells and may have important implications for the design of artificial tissues and the development of novel therapeutic strategies.”

Related Links:
Hebrew University of Jerusalem