According to the CDC, vaccines contain ingredients called antigens, which help the body develop protection against specific diseases. Vaccines also contain very small amounts of ingredients that are necessary to make the vaccine and protect it from spoiling before it is used. The FDA website has a list of each vaccine and what the ingredients are. Both Pfizer and Moderna are mRNA vaccines that send the body cell instructions for making a spike protein that will train the immune system to recognize it. The J&J vaccine is a carrier vaccine made with adenovirus as a shell to carry genetic code o the spike proteins cells. READ MORE: https://www.wcnc.com/article/news/ver...