An '''antigen''' is a specialized [[protein]], though sometimes it can be a carbohydrate instead. When an antigen is injected into the bloodstream, as through vaccination, it causes the body to produce [[antibodies]].
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An '''antigen''' is a specialized [[protein]], though sometimes it can be a carbohydrate instead. When an antigen is injected into the bloodstream, as through vaccination, it causes the body to produce [[antibodies]]. Having too much antigen in the body can cause jaundice.