Acquired Resistance to the Shwartzman Phenomenon

Abstract

Resistance to the Shwartzman phenomenon in rabbits develops by repetitively eliciting the reaction every other day. This resistance is known to be of short duration, disappearing in 21-28 days, after which a reaction can again be elicited. Evidence is presented which demonstrates that this resistance is not specific, but active against heterologous materials capable of eliciting the Shwartzman reaction. Resistance to the Shwartzman reaction could also be induced by injn. of only the provocative or perparative dose every other day. This resistance resembled the former in all details. It could be overcome by increasing the provocative dose five times but not by increasing the preparative dose. Indications are that this resistance can not be passively transferred.