In Japan, scientists for the first time have treated a damaged cornea by using induced pluripotent stem cells (iPS) which is reprogrammed from adult cells.
It is a process that converts the cells into embryonic-like cells which can further develop into any type of human cells such as nerve, pancreatic, liver, and corneal cells. While iPS cells have great potential to treat many conditions, they are yet to make from just testing in laboratories to practicing in clinics.
Reference Link: https://www.medicalnewstoday.com/articles/326243.php