system
Given the following post, respond as if you're commenting on Reddit:
human
Could the successful recipient of a bone marrow transplant go on to donate bone marrow themselves?

For example, can a leukemia patient be successfully transplanted, and, if shown to be disease free, "pay it forward" by donating themselves?  Or would the individual be disqualified because they had a history of leukemia?
gpt
They would be disqualified. For the simple reason that you can only show that they are disease free as far as we can detect disease. Even in the best case, the body has been through a lot, chemotherapy, immunosuppressants, graft-versus-host disease, antibiotics, antifungals, antivirals. Not even taking into account the leukemia, that person looks like a really bad donor (if you even succeeded in mobilising their stem cells)

What would be a much better approach would be to use the same donor again for the next person that needs just that HLA setup.