That's a pretty important component as well.
I've worked with bone marrow stem cells and neural stem cells. Once active and concentrated, the cells are amazing. Basically, you look for a gene or protein associated with recovery, and they are expressing them. If you take culture medium from these cells and culture other cells in them, these cells start expressing everything related to recovery.
IMO, there isn't a tissue in your body that doesn't have stem cells in it. Really great things are on the way.
My wife and I are currently debating whether or not to save the cord blood cells from our upcoming kid. We've treated rats that had stroke with these cells, with marked improvements.