This is probably a long shot kind of concern, but if the Pfizer vaccine for Covid-19 works by inducing our bodies to produce the proteins which our immune systems then attack, then wouldn't this be a lot like an autoimmune disease, whereby our body is attacking itself? If these proteins were to be produced indefinitely, in theory they could collect on other tissues, such as joint tissues, and the immune system may attack those healthy tissues in the process of attacking the proteins. Something very much like this collateral damage of healthy tissues is what happens with Rheumatoid Arthritis. Does the vaccine only induce our bodies to make the protein for a very short period of time? Thanks.