THE SPECIFICITY OF ALLERGIC REACTIONS

Abstract

"Gastric feeding" of adult guinea pigs with dinitrochlorobenzene (DCB) resulted in a specific unresponsiveness to sensitization with the specific contact hapten. When such animals were later sensitized with an "in vitro" conjugate of a hapten with a heterologous protein such as dinitrophenyl-hen egg albumin (DNP''HEA), an immune response similar to that in the controls occurred both to the hapten and to the carrier protein. The presence of circulating anti-DNP antibodies from sensitization with DNP-HEA did not affect the unresponsiveness to the specific contact hapten, regardless of whether these antibodies were present before or after induction of tolerance. Sensitization with picryl chloride (a cross-reacting hapten), either before or after "gastric feeding" of DCB, did not affect the state of unresponsiveness to DNP. Acquired tolerance seems to have a specificity which, like that of delayed hyper-sensitivity, is oriented toward the carrier protein.