In new research, University of Freiburg researchers have introduced genetic information with an optical remote control. As a result, only cells that are illuminated with red light take up the desired genes. To do this, the scientists modified a type of viral vector known as an AAV vector, which is already in clinical use.
"We took away the viral vector's ability to dock with cells," says professor Maximilian Hörner, "which is an essential step before the genetic material can be introduced."
To enable this control by light, the team have taken a red light photoreceptor system from the plant Arabidopsis thaliana (thale cress). This system comprises two proteins, PhyB and PIF, which bind to each other as soon as PhyB is illuminated with red light. The Freiburg team placed the protein PIF on the surface of the viral vector and modified the other protein PhyB so that it could bind to human cells. Once this modified vector, called OptoAAV, is in a cell culture along with the cell-binding protein, the protein binds to all cells. The study was published in Science Advances.
"If a selected cell is now illuminated with red light, the modified vector can bind to this cell and introduce the target genes into the illuminated cell," Hörner explains.
This new approach allows the researchers to introduce target genes into the desired cells within a tissue culture.
"As these viral vectors become more widely used in the therapeutic field," professor Wilfried Weber says, "we think this new technology has the potential to make such biomedical applications more precise."
Photo: In their new method, the Freiburg researchers introduce genetic information with an optical remote control. Credit: Michal Roessler