Thermoresponsive Hydrogel as a Delivery Scaffold for Transfected Rat Mesenchymal Stem Cells

The concept of stem cells as a therapeutic agent has been gaining momentum. A common mode of administration of these cells is by direct injection into the target tissue. This can result in many of the cells being lost due to reflux from the injection site leading to a local loss of implanted cells. PoligoGel is a nontoxic hydrogel with an LCST near body temperature. It is also shown to be nontoxic to multiple cell types, and in the case of rat mesenchymal stem cells does not alter their differentiative capacity, either by inducing differentiation, or limiting the potential for subsequent differentiation after removal from the gel. Embedding cells in PoligoGel also does not interfere with the cells' ability to delivery therapeutic growth factors post transfection with plasmid DNA. Here a thermoresponsive hydrogel, PoligoGel, is shown to have potential to act as a scaffold for the retention of cells at an injection site, mitigating migration or washing of the cells away from the target site after implantation.