How does one communicate with cells? One way is with optical signals, such as those used in optogenetics to activate or deactivate brain cells, but when the cells are too deep in the body, how can you get the signal through the layers of tissue? Researchers at Massachusetts General Hospital have an answer in the form of a hydrogel implant.
Hydrogels are a class of polymers which hold a great deal of water and can be used as scaffolding for implants. In this research, the hydrogel was carefully designed first, to ensure it could deliver or detect a light signal, and then filled with cells before being implanted in a mouse's body. Depending on the cells in the hydrogel, the implant would either carry a signal from an optical fiber to the cells, causing a reaction, or a reaction within the body would cause the cells to produce light, which would exit the body through the optical fiber. Both scenarios were tested successfully in mice.
This is the first time optical communication has been achieved with cells located deep within the body. Hopefully with further study, way to improve the implant's efficacy can be determined, including a means for it to operate without the optical fiber that has to pass through the skin.
Source: Massachusetts General Hospital