Inkjet Gene Printing: a Novel Approach to Achieve Gene Modified Cells for Tissue Engineering

In this study a novel method of simultaneous gene transfection and cell delivery based on inkjet printing technology is described. Plasmids encoding green fluorescent protein (GFP) were co-printed with living cells (porcine aortic endothelial (PAE) cells) through the ink cartridge nozzles of modified commercial inkjet printers. Agaorse gel electrophoresis analysis showed there was no obvious structural alteration or damage to these plasmids after printing. Transfection efficiency of the printed cells, determined by GFP expression, was over 10% and post-transfection cell viability was over 90%. We showed that printing conditions, such as plasmid concentration, cartridge model, and plasmid size influenced gene transfection efficiency. Moreover, genetically modified PAE cells were accurately delivered to target sites within a three dimensional fibrin gel scaffold and expressed GFP in vitro and in vivo when implanted into mice. These results demonstrate that inkjet printing technology is able to simultaneously transfect genes into cells as well as precisely deliver these cell populations to target sites. This technology may facilitate the development of effective cell-based therapies by combining gene therapy with living cells that can be delivered to target sites.