“Researchers Create First Human Heart Cells That Can Be Paced With Light”
September 20, 2011 Leave a comment
From ScienceDaily: heart cells have been engineered that will contract in response to light, with potential uses in the future as a new kind of pacemaker, made from a patient’s own stem cells.
These heart cells contract in response to sodium entering the cells – basically the same way neurons send signals. To make light-sensitive heart cells or neurons, you insert the DNA encoding rhodopsin – a channel on the cell membrane in retinal cells, which is what allows them to send messages in response to light (and thus, vision!). So now that they’re expressing rhodopsin, when these heart cells are exposed to light, the rhodopsin channels will open, allowing in sodium from outside the cell, causing them to contract.
Abilez holds up a finger as if to say, “Wait,” and reaches for a small lever hidden behind the microscope. With the same finger, he flips the lever up. A pale, blue light floods the petri dish. Abilez flicks the light off and then on; first fast and then slow. Each time his finger goes up, the heart cells contract in concert with the light…
In the near term, say the researchers, the advance will provide new insight into heart function. In the long term, however, the development could lead to an era of novel, light-based pacemakers and genetically matched tissue patches that replace muscle damaged by a heart attack.