when some foreign particle enters the human body then immune system reacts to it and tries to destroy it, be it anything even an organ from another person. Why immune system does not react to titanium plates-that are attached to fix the broken bones?

Question

I got a titanium plate screwed in my lower jaw that got broken previously. I recently read somewhere that immune system attacks every foreign particle, even transplanted organs that’s why one has to be on immunosuppressants to live with transplanted organs.

In: 3

Answer 1

Your immune system is playing a giant game of “Papers please”

When your immune system bumps into something it checks its identification to make sure its recognized. If there is something on the papers (markers on the outside) that it doesn’t recognize or seems suspicious (shiny staples) it throws up the alarm and the rest of the guards come out

There’s a catch here that your body didn’t plan for. If it bumps into something that’s like “gosh i just don’t have papers” it goes “oh alright, you can go” and moves on. This is what lets O- blood be the universal donor, it doesn’t have any markers on it for the immune system to react to. Your body isn’t really sorting things into Self vs Not-Self, its really sorting into Not-Self vs Not-Not-Self

Titanium is similar to O- blood in that its very non-reactive and when your immune system bumps into it to check its papers they get no response and just move on. Its super hard to break titanium bonds to allow it to form compounds so almost all titanium based things are super stable and don’t react, and if you do get them to react *RUN*