Studying cells grown in a lab, called cell cultures, is essential to our understanding of their growth and functioning in our body. A common cell culture used in such studies is called adherent cells, which require a substrate or a surface to grow on. The chosen substrate usually resembles the extracellular matrix.
Researchers at the Indian Institute of Technology Bombay have shown that cell density, the number of cells grown on a unit volume, can also influence the morphology and function of cells.
Adherent cells form ‘adhesion sites’, a set of localised contact points on the substrate, with the help of proteins called integrins. These integrins are connected to actin fibres of the cell’s skeleton via a complex group of molecules called focal adhesions.
When a cell adheres to a substrate, mechanical stimuli are transmitted and converted to biochemical signals through the focal adhesions, and this is crucial for various cellular processes and functions.
In the current study, published in the journal Biomaterials Science, the researchers have observed the growth and cellular traction—the stress exerted by human mesenchymal stem cells—as it spreads on a polyacrylamide substrate.