"Form follows function!" was the credo of early 20th century architects making design choices based on the intended use of the structure. Cell biologists may be turning that on its head. New research* by a team working at the National Institute of Standards and Technology (NIST) reinforces the idea that stem cells can be induced to develop into specific types of cells solely by controlling their shape. The results may be important to the design of materials to induce the regeneration of lost or damaged tissues in the body.
Tissue engineering seeks to repair or re-grow damaged body tissues, often using some form of stem cells. Stem cells are basic repair units in the body that have the ability to develop into any of several different forms. The NIST experiments looked at primary human bone marrow stromal cells, adult stem cells that can be isolated from bone marrow and can "differentiate" into bone, fat or cartilage cells, depending.
"Depending on what?" is one of the key questions in tissue engineering. How do you ensure that the stem cells turn into the type you need? Chemical cues have been known to work in cases where researchers have identified the proper additivesa hormone in the case of bone cells. Other research has suggested that cell differentiation on flat surfaces can be controlled by patterning the surface to restrict the locations where growing cells can attach themselves.
The experiments at NIST are believed to be the first head-to-head comparison of five popular tissue scaffold designs to examine the effect of architecture alone on bone marrow cells without adding any biochemical supplements other than cell growth medium. The scaffolds, made of a biocompatible polymer, are meant to provide a temporary implant that gives cells a firm structure on which to grow and ultimately rebuild tissue. The experiment included structures made by leaching and foaming processes (resulting in microscopic structures looking like clum
|Contact: Michael Baum|
National Institute of Standards and Technology (NIST)