Stem cells: Small 3/2010

The cover picture shows several human mesenchymal stem cells (green with blue nuclei) clustered around a stiff polymeric microstructure (blue) in a three-dimensional matrix. The microstructures are fabricated using photolithographic techniques and then suspended with stem cells in the matrix. The stem cells migrate and attach to the microstructures, and although the volume percentage of the microstructures within the matrix is quite low (0.07%), stem-cell morphology, clustering, and gene expression are significantly different compared to without the microstructures. The knowledge of how physical and mechanical cues in three dimensions can influence cellular function is necessary for the development of novel platforms for regenerative therapy. For more information, please read the Communication “Three-Dimensional Culture with Stiff Microstructures Increases Proliferation and Slows Osteogenic Differentiation of Human Mesenchymal Stem Cells by B. Russell et al., beginning on page 355.