A new technology under development by an academic–industry partnership protects oral vaccines from destruction by the digestive system. From the mouth to the small intestine, the digestive system presents a series of challenges designed to protect us by killing ingested bacteria. If a microbe survives the digestive enzymes in saliva and the corrosive acid of the stomach, the toxic fat-emulsifying bile acids in the small intestine will probably kill it. As a first line of defense against disease and infection, the digestive system is an extremely efficient bactericide.
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