Synthetic gene circuits that improve stem cell quality

Because iPS cells can be made into just about any cell type in the body, they have great promise for cell therapies. One major problem, however, is that not all reprogramming cells successfully become iPS cells, resulting in an unwanted cell mixture.

Further, when differentiating iPS cells, some cells are only partially differentiated, again leaving an unwanted cell mixture.

To extract the desired cell types, CiRA researchers report in Science Advances new synthetic RNA technology consisting of ON and OFF switches. These switches control specific genes to kill contaminating cells while leaving desired cells unscathed at rates superior to standard techniques.

"The standard method for cell purification is to use fluorescence-activated cell sorting or magnetic-activated cell sorting," said CiRA Assistant Professor Yoshihiko Fujita, one of the authors of the study. "But antibodies are needed, which makes these approaches costly, and the process damages many cells."

The Hirohide Saito lab, in which Fujita is a member, has therefore been developing synthetic RNA they call "RNA switches" as an alternative. Unlike antibodies, which react with proteins on the surface of the cell, the RNA switch binds with miRNA naturally expressed inside the cell.

https://phys.org/news/2022-01-synthetic-gene-circuits-stem-cell.html