Abstract
In 2004, Shen et al. developed a safe and efficient gene transfer system using a DNA‐apatite composite layer. We have recently succeeded in improving further the gene transfer efficiency by immobilizing a cell adhesion molecule laminin, in a DNA‐apatite composite layer. In this study, we showed that not only laminin but fibronectin immobilized in a DNA‐apatite composite layer enhances cell adhesion and cell spreading on the layer, thereby markedly improving the gene transfer efficiency. Therefore, the immobilization of a cell adhesion molecule in a DNA‐apatite composite layer is crucial for improving the gene transfer efficiency. By using fibronectin instead of laminin and optimizing the condition to prepare the fibronectin‐DNA‐apatite composite layer, the amount (weight) of cell adhesion molecule required was reduced to approximately one‐fourth while retaining the relatively high gene transfer efficiency. It was also shown that the resulting fibronectin‐DNA‐apatite composite layer prepared under the optimized condition mediated the area‐specific gene transfer on its surface, that is, DNA was preferentially transferred to the cells adhering to the surface of the fibronectin‐DNA‐apatite composite layer. The present gene transfer system with potential for area‐specific transfection and advantages of safety and relatively high efficiency would be useful in tissue engineering applications, gene therapy, and production of transfection microarrays. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010