Induction of tolerance to dinitrophenylated bovine IgG in pigs

Intraveneous administration of soluble 2,4‐dinitrophenyl(DNP)‐conjugated bovine IgG to pigs led to induction of tolerance to this antigen. A single dose of 100 mg soluble conjugate per animal resulted in complete tolerance which lasted at least 80 days. Lower doses led to partial tolerance. Induction of tolerance in pigs was shown to be a process taking several days to complete. Animals exhibiting tolerance when challenged by the homologous conjugate still synthesized significant amounts of antibody when challenged by the carrier protein or by a conjugate of the 2,4‐dinitrophenyl group with a different carrier.