This is done today by stem cell banks. They're typically used for treatment of diseases like leukemia. Public stem cell banks work similarly to blood banks, a

This is done today by stem cell banks. They're typically used for treatment of diseases like leukemia. Public stem cell banks work similarly to blood banks, and there are private banks where your stem cells are saved for your family. Private banks are, in general, much more expensive. From what I understand, though, stem cells don't last longer than a few years in storage. Making private banks a less useful.