Gene transfection on micropatterned cells

Gene therapy has been intensively studied in the laboratories with the hope of treating human diseases like cancer, neural degeneration, HIV and many others. The conventional method for investigating gene delivery efficiency in vitro is conducted by performing transfection in the culture well plates. Using this method an average value for the entire population is achieved. More recently, there has been increasing interest in achieving qualitative and quantitative analytical information of single cell but this cannot be attained by doing transfection in a culture plate, micropatterning of cells is essential for such study. Development of a micropatterned cell biochip is a promising technology since a chip with a variety of cells spotted onto it will facilitate high throughput analysis. Micropatterning of cells has been achieved using photolithography, soft lithography and PDMS stencils. All these methods require photolithography. The necessity of using photolithography equipment has long stood in the way of easy patterning of cells on substrates. Addressing this difficulty, we use an inexpensive and easy micropatterning of single cells in the laboratory, which does not require any lithographic processes or surface modification of the substrate prior to seeding of the cells, and can be achieved, by the use of easily available laboratory equipments. This method utilizes a commercially available autoclavable knit fiber mesh. The mesh was laid on the desired substrate and cell culture suspension was seeded on the mesh. After achieving micropatterned cells, transfection of EGFP was conducted using non viral vectors. The cell seeding, although uniform, was not extensive. Green fluorescence was observed on certain spots. This study demonstrates the use of a cell biochip for studying transfection efficiency. The application of a cell biochip can be extended to other fields, like drug delivery. This method of micropatterning cells completely bypasses the use of photolithography at any stage and it utilizes both cheap and easily available materials. We hope that a well patterned single cell biochip will be available in near future for high throughput analysis.