Eliciting antigenicities of benzylpenicillin, ampicillin and carbenicillin preparations examined with the reagin-mediated passive cutaneous anaphylaxis system

Antigenicity of semisynthetic penicillin preparations to evoke systemic anaphylactic reactions in animal models

Four commercially available penicillin preparations (benzylpenicillin, aminobenzylpenicillin, carbenicillin and sulbenicillin) and two kinds of the new semisynthetic penicillin preparations (mezlocillin and piperacillin) evoked systemic anaphylactic reactions in guinea pigs immunized with one of the following penicillin-Ascaris extract (As) conjugates in aluminum hydroxide gel (alum), i.e., benzylpenicilloyl (BPO)-As, aminobenzylpenicilloyl (ABPO)-As, carbenicilloyl (CBPO)-As, sulbenicilloyl (SBPO)-As, mezlocillin-As conjugate (MEZ-As) and piperacillin-As conjugate (PIP-As). The tracheal chains prepared from the tracheas of the guinea pigs immunized with BPO-As, MEZ-As, or PIP-As revealed anaphylactic contractions in vitro on addition of benzylpenicillin, mezlocillin, or piperacillin preparations. These results indicated that the semisynthetic penicillin preparations as well as benzylpenicillin preparation have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with penicillin-As conjugate. Such guinea pigs seem to be suitable animals for investigations of penicillin allergy.

Benzylpenicillin preparations can evoke a systemic anaphylactic reaction in guinea pigs

All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum bydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy.