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Mesenchymal stem cells (MSC) have been shown to aid tissue healing by virtue of the factors they secrete that affect the surrounding cells. Direct or IV injection of these cells is the most feasible way of administration, however, this is not always possible especially when the target area is hollow. Scaffolds using collagen,chondroitin, and hyaluron have been studied for tissue engineering in orthopedics The basis of this pilot study is to evaluate the progress of MSC in a scaffold. Our aim is to evaluate hydrogel as a scaffold and study if MSC survive, proliferate and migrate into the surrounding.Method: Bone marrow from femurs of rats was harvested and cultured according to our laboratory protocol. Cultured cells were passage every 3 days until passage 4 was reached. Cells were sorted by flow cytometry by positive selection using intracellular adhesion molecule (ICAM-1)(PE+ve). A hydrogel pellet was created by mixing 300ul of hyaluronic acid and 8ul of hydrogen peroxide (H202) which was used for crosslinking. One million MSC were then suspended in a 1ml solution an introduced into the hydrogel pellet.and plated using a basic stem cell media. Cells were maintained and observed every 2-3 days for 3 weeks. At 3 weeks the pellets were digested using a 5% collagenase solution to free the MSC and resubmitted for sorting by flow cytometry. A separate passage 4 of MSC without hydrogel was submitted for flow cytometry as controls. The percentage of positively sorted MSC cells from hydrogel grown was then compared to the MSC without the hydrogel matrix.Results: Sorted MSC from the bone marrow showed 54.1% (494,567 of 914,167) MSC-PE (+)prior to hydrogel crosslink. One week later MSC were seen leaking through the hydrogel into the culture media (figure). These free cells were sorted, which showed 18.8%(58,068 of 748,336) MSC-PE (+) cells. At three weeks, MSC that were freed from the Hydrogel showed 13.7%(110,423 of 802,464) MSC-PE (+), in comparison with the control MSC that showed 37.2% (523,189 of 1,476,723).Conclusion. The pilot study demonstrates that Hydrogel can provide a scaffold and provide a temporary milieu where MSC can survive and traverse into the surrounding areas. This scaffold can contain MSC in an area for a few weeks and thus is a feasible way of delivering cells. It can be a valuable in future cellular therapies that target areas that need to be filled.