• 1 January 1964
    • journal article
    • research article
    • Vol. 7 (6), 700-+
Abstract
Both immediate and delayed cutaneous reactions were found to be present in rats actively sensitized by the injection of antigen plus Bordetella pertussis organisms. Delayed hypersensitivity preceded the appearance of "mast cell sensitizing" antibody (MCSAb) in those animals which were only fully susceptible to anaphylaxis when both delayed and immediate reactions had reached their maximum. Passive anaphylaxis with MCSAb was fatal only when transferred to actively sensitized rats at a time when the animals had delayed cutaneous reactions but were not yet fully susceptible to anaphylaxis. It is suggested that anaphylaxis in rats is due to an additive or synergistic effect between immediate and delayed hypersensitivities.