First, here's a quote from an FDA advisory committee report:

"Cells are able to uptake mRNA delivered in an LNP, translate the mRNA into its associated protein, and then express that protein viral antigen(s) on the cell surface to elicit an immune response."

Source (PDF):
https://www.fda.gov/media/144452/download
The quote is on page 10 of the PDF (page 9 by the document numbering). You can find it by searching "surface".

Here's another paper accepted for publication, which confirms the amounts of free spike circulating in the blood are tiny and transient, and are seen only in the first 10 days after the first injection (see figure 1):

https://www.deplatformdisease.com/blog/spike-protein-circulating-in-the-vaccinated-what-does-it-mean

Now, here's the definition of Lupus, from Wikipedia:

"Lupus, technically known as systemic lupus erythematosus, is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body."

"Tissue" means cells. So are vaccinated people going to develop something resembling Lupus? Asking for a friend...

Oh, and the funniest thing is, one of the treatments used for Lupus is...Hydroxychloroquine! You can't make this stuff up...