eli5: Why does donating blood risk triggering an existing autoimmune disorder?

Question

This is not a false premise, I am not eligible to donate blood for this reason.

In: 7

Answer 1

Off the top of my head I can’t think of any reason why it would be dangerous for *you*, but if you have an autoimmune disease that involves, say, self-reactive T cells or antibodies, then that poses a danger to the recipient.

E: MSc in immunology