Endogenous and exogenous proteins, and fragments thereof, are chemically modified outside the body of an animal so that when injected into the animal they produce more antibodies against the unmodified protein than would injection of the unmodified protein or fragment alone. The chemical modification...http://www.google.de/patents/US4713366?utm_source=gb-gplus-sharePatent US4713366 - Antigenic modification of polypeptides
