Anaphylaxis following intranasal challenge of mice sensitized with ovalbumin

Mice sensitized with two intraperitoneal injections of ovalbumin and challenged intranasally with the same antigen developed a non-fatal anaphylactic shock peaking in severity 30 min after challenge. Increases in haematocrit were noted which corresponded to the severity of signs of shock displayed by mice. Severity of shock also correlated with IgE and IgG levels. Sensitization by the nasal route, and use of B. pertussis vaccine as adjuvant had no qualitative effect upon the response. Cobra venom factor depletion of C3 in vivo did not alter the response of mice, which suggests anaphylaxis did not involve complement activation. Sensitivity was not transferrable to non-immune mice with serum. Passive sensitization with polyclonal and monoclonal antibodies produced inconsistent results. Possible mechanisms of anaphylaxis are discussed.