In short, we're still far away from using it in humans (10+ years). Currently, all companies working on this are in pre-clinical stage, with turn.bio as the closest, expecting to go into clinical trials late this year.
This tech is exciting but there are still a lot of limitations:
- Risk of cancer: this technology is based on the work of Yamanaka in 2006, who discovered 4 factors that can turn any cells into pluripotent stem cells. The work in the OP article basically used the same 4 factors, but only partially, so that the cells became "younger" without losing their identities (i.e. turning into stem cells). This requires understanding the right dosage for every cell type so we don't go overboard and turn them into dedifferentiated cells which could lead to cancer
- Cell specificity, microenvironment, etc.: reprogramming is finicky and the right dosage is dependent on the cell type or the environment around the cells. This is important because you have to figure out the right dosage for each cell type so as to avoid cancer
- Delivery: it's easy to deliver gene therapy to skin cells on a dish, not so much to other cell types or organs in the bodies -- that's why we have not seen very impressive results when this is used on live normal mice