Berkeley Researchers Lay Groundwork for Cell Version of DNA Chip
A new technique in which single strands of synthetic DNA are used to firmly fasten biological cells to non-biological surfaces has been developed by researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley. This technique holds promise for a wide variety of applications, including biosensors, drug-screening technologies, the growing of artificial tissues and the design of neural networks.
Figure A: To test their cell adhesion system, researchers anchored single-stranded DNA to gold pads inside microfluidic chips. When the pads were washed with a mixture of DNA-coated cells, only those cells with complementary DNA adhered to the pads. Figure B: With a cell adhesion system based on matching DNA sequences, different cell types can be selectively attached to a chip surface in precise patterns.
Once it was established that cell surfaces could be coated with single-stranded DNA, Chandra worked with Douglas to demonstrate that this adhesion system could be used to attach cells to a non-biological surface. Douglas is a student under Mathies, director of UCB’s Center for Analytical Biotechnology. Chandra and Douglas used a commercial chemical handle, the sulfur-based thiolate ion, to anchor single-stranded DNA onto gold pads, which were incorporated into microfluidic chips through standard photolithography. After the DNA-coated Jurkat cells were rinsed over the chips, fluorescence microscopy revealed that only those cells coated with single-stranded DNA complementary to the anchored DNA adhered to the gold pads. Cells that were otherwise identical but bearing mismatched DNA sequences were washed away.
