I bought some of Histogen's Regenica, and I've been applying it with a dermaroller for about a week.
No detectable results yet.
I will keep everyone updated.
I have no reason to believe that this product is any different than the one they use for hair regrowth. According to their submission to the Stem Cell Summit 2008, their Regenica product contains WNT factors. They don't talk about filtering out particular growth factors but collecting all of them.