Regenerating cartilage has been a goal for a long time. The science is exciting, but the real milestone will be whether it works safely in large clinical trials.

I'd bet it will work since it worked on human tissue

but there will be unintended side-effects with other muscle and organ growth that will be unacceptable

that protein sounds like nature evolved some kind of rate-limiter

but it's fascinating they found it

maybe it can be safely used for short spurts like a couple weeks at a time

(and I also bet it will become a performance-enhancing drug WADA has to test for)