In 1925, Gaston Ramon, a French veterinarian, noticed that horses vaccinated with a diphtheria vaccine had a higher number of antibodies in their blood if they developed inflammation at the site of injection.1 Curious to see if he could improve the antibody titers by deliberately causing inflammation, Ramon added household items such as breadcrumbs, soap, starch, and agar to the vaccine. With his theory proven correct, vaccine adjuvants were born.