AstraZeneca is NOT an mRNA vaccine. It is a viral vector vaccine, Just to be accurate. It seems to be even more invasive than the mRNA.

They use the shell of an adenovirus and put DNA inside, it then, as a virus would, enters a cell and deposits the internal DNA strand into the cell nucleus which then commands the cell nucleus to create the mRNA strand that leaves the nucleus where it will then create copies of the spike protein.