Highly efficient gene transfer system using a laminin-DNA-apatite composite layer

We have recently developed a safe and efficient gene transfer system using a laminin-DNA-apatite composite layer. The objectives of the present study were to fully characterize and optimize the laminin-DNA-apatite composite layer in relation to the efficiency of gene transfer and to demonstrate the feasibility of the composite layer in the induction of cell differentiation.

The laminin-DNA-apatite composite layer was prepared under various conditions. The efficiency of gene transfer on the resulting composite layer was evaluated using luciferase and ss-galactosidase gene expression assay systems. A laminin-DNA-apatite composite layer, prepared under the optimized condition using a plasmid including cDNA of nerve growth factor (NGF), was then applied to the neuron-like differentiation of PC12 cells.

The laminin content of the laminin-DNA-apatite composite layer was found to be a dominant factor improving the efficiency of gene transfer rather than the DNA content. The cell adhesion property of laminin in the composite layer should be responsible for the improvement in efficiency of gene transfer because the immobilization of albumin without the cell adhesion property in a DNA-apatite composite layer had no effect on the efficiency of gene transfer. A laminin-DNA-apatite composite layer, prepared under the optimized condition using a plasmid including cDNA of NGF, successfully induced the neuron-like differentiation of PC12 cells.

The present gene transfer system, with the potential to control cell differentiation and having features of safety and relatively high and controllable efficiency, would be a useful tool for tissue engineering applications and the production of transfection microarrays.