[masterdragon]

Fascinating new research. 

Stem Cell Research is being done for reducing vision loss as people age: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/senescence

However, stem cells become less useful as they age.  They can be kept in a less active "quiescent" state to reduce aging until they are activated.  This is useful to prolong the life of the stem cell, but can be risky as the cells become vulnerable.  https://www.cell.com/trends/cell-biology/fulltext/S0962-8924(19)30081-9