New Research on Mesenchymal Stem Cells’ Plasticity

New Research on Mesenchymal Stem Cells’ Plasticity

Researchers at the University of Pennsylvania have found out that the environment surrounding mesenchymal stem cells is highly determinative of how the cells will differentiate. The press release says, “According to the researchers, soft microenvironments that mimic the brain guide the cells toward becoming neurons, stiffer microenvironments that mimic muscle guide the cells toward becoming muscle cells and comparatively rigid microenvironments guide the cells toward becoming bone.” Cells have structures called the skeleton and use chemical signals as we use muscles to move; the stem cells can therefore “feel” how hard they are pressing against their surrounding environment. This triggers particular chemical signals telling them how to differentiate.

Because the cells are in part triggered to differentiate through their physical environment, changes to the environment might cause the cells to fail to differentiate even if the chemical conditions are right. The example given in the press release is that of heart damage, where scar tissue prevents the cells from differentiating into heart muscle tissue.

The researchers hope that this work can be used to create stem-cell specific environments in the lab so that appropriate cells could be transplanted. Possibilities of this were shown by the fact that the cells reacted differently to different firmness in the gel culture medium.

I wonder if there are similar conditions for the growth of embryonic stem cells. On the face of it it seems like their earliest signals would have to be entirely chemical, since there is no variance in the environment, but perhaps as the embryo develops physical environments become significant to the fetal stem cells.