They picked livers: of course, they should have picked pancreases!
It is a really interesting paper because it appears to be a new approach to engineering organs from stem cells. First, they studied what genes would likely influence stem cells into developing as liver cells. Then they used CRISPRa to modify the stem cells so that the right genes would be in place. Then they grew the cells in vitro (Petri dish). They obtained mini livers (organelles).
When they injected the resulting mini livers into mice with liver disease, they saw an increase in mouse lifespan.
This is not so far from creating and injecting mini pancreases! Of course, they’d have to do it repeatedly, because we’ll keep on destroying them.
The original paper is here: https://www.cell.com/cell-systems/fulltext/S2405-4712(20)30420-8