BusinessWeek in running an article on the use of proteins - rather than stem cells - for regenerative medicine. It concludes that there is a great deal of promise in this field, but things are off to a slow and somewhat rocky start. Researchers are a long way away from the level of knowledge they would like to have: "It's very promising. But there's still a lot of biology and molecular engineering to be done." All fields of scientific endeavor are littered with failures ... at least at first. A wide diversity of efforts to understand and manipulate the workings of the human body is exactly what must happen if we are to extend the healthy human life span any time soon.