The goal of Dr. Xiao-Dong Chen's lab is to reconstitute tissue-specific stem cell niche in vitro to control stem cell fate for tissue regenerative purposes. Mesenchymal stem cells (MSCs) are potentially useful for cell-based tissue engineering including the repair of skeletal tissue in non-union fractures or other damaged tissue or organs caused by many age-related diseases, and reconstructive surgery following trauma or removal tumors.
However, MSCs are rare in bone marrow (approximately 0.01% to 0.001%), and they are difficult to expand in standard culture systems without losing their properties. This situation has impaired the study of cellular and molecular mechanisms underlying control of MSC behavior and thereby limits their therapeutic potential.
Our group was the first to establish a culture system, using cell-free native ECM made by bone marrow stromal cells, for quickly growing large numbers of high-quality MSCs from different sources, including bone marrow and umbilical cord blood. To closely replicate the tissue-specific microenvironment (niche) ex vivo, we have extended our technology by developing a variety of 3D tissue-specific scaffolds for: 1) rejuvenating MSCs from the elderly to establish a high-quality autologous stem cell bank in order to provide a sufficient number of cells for treating age-related diseases, 2) inducing MSCs differentiation into the salivary gland epithelial cell lineage for repairing damaged salivary gland, and 3) improving preservation of pancreatic islet function and reducing immunogenicity for treating type 1 diabetes using allograft transplantation. Based on the knowledge gleaned from our established native tissue-specific ECMs (TS-ECMs), we have been developing a series of defined TS-ECMs to selectively control the fate of MSCs in order to obtain desired homogenous population of cells (muscle, bone, cartilage, skin, etc) for tissue regenerative purposes.