Microfabricator Potomac Photonics has completed rapid prototyping of precision 3-D printed parts for Boston University to support the school's stem cell research, the company annnounced last week. Stem cells have enormous potential in medical research because they can differentiate into specialized cell types and may one day provide a renewable source of replacement cells for patients requiring organ transplants or who have disorders such as Parkinson's, diabetes and cardivascular disease. Understanding and controlling stem cell differentiation in vitro is proving to be a major challenge, BU investigators say, because cells can interact with each other either through direct contact or by cell-secreted factors. What is needed is a more controlled cell microenvironment to shed light on factors that influence cell behavior. Using a high-resolution 3-D printer, Potomac Photonics provided the controlled environment by fabricating precision stencils that pattern seeded stem cells in such a way that the cells are grown in a defined arrangement relative to each other. By using various stencils, the researchers hope to determine how the relative position of the cells affect their ability to divide and to create new cells that are different from themselves. The work was performed by Potomac Photonics' Educational Manufacturing Initiative. For more information, visit: www.potomac-laser.com