Novel gene-transferring scaffolds having a cell adhesion molecule-DNA-apatite nanocomposite surface.

A low efficiency has long been the most critical problem of conventional gene-transferring systems using calcium phosphates, and this was successfully improved on by using a laminin-DNA-apatite composite (LD-Ap) layer. The gene-transferring efficiency of the LD-Ap surface was 1-2 orders of magnitude higher than that of a DNA-calcium phosphate composite surface. This is because laminin enhances cell adhesion and spreading, and this provides regions of high DNA concentration between a cell and the LD-Ap surface. The efficiency of gene transfer of the LD-Ap surface was equivalent to, or even higher than that mediated using a commercial lipid-based transfection reagent applied using the manufacturer's recommended optimum conditions. In addition, the gene-transferring efficiency of our system could be controlled by changing the laminin and DNA content in the LD-Ap layer. Moreover, our system is composed of highly safe reagents: apatite, DNA and laminin, all of which are present in the human body. Hence, the LD-Ap surface, which enhances cell attachment on its surface, and mediates a safe, highly efficient and controllable gene transfer, is highly applicable to tissue engineering and gene therapy applications.