I was quite surprised when I saw this reported as news, since Heinlein wrote about it forever ago. Either something has gone wrong with the field of life extension, or this experiment ignores some major reason why it won't help anyone, or I should be paying more attention to Heinlein.
In experiments performed on mice, blood transfusions from young mice reversed age-related markers in older mice. The protein involved is identical in humans.
http://mic.com/articles/88851/harvard-scientists-may-have-just-unlocked-the-secret-to-staying-young-forever