ANAPHYLACTIC SENSITIZING CAPACITY OF HEMOPHILUS PERTUSSIS IN MICE

Abstract

It is very difficult to induce anaphylactic shock in mice injected with heterologous protein, but Parfentjev et al. and Kind reported that sensitization together with pertussis vaccine results in the easy production of anaphylactic shock in mice. However, the mechanisms are yet unknown. In the present experiment conducted in order to make it clear, the following results were obtained:
In each group of mice injected intraperitoneally with normal horse serum
together with H. pertussis Phase I, H. pertussis Phase III, H. parapertussis and H. bronchisepticus, respectively, anaphylactic shock to horse serum developed at a high rate only among those receiving H. pertussis Phase I, but not extensively among the other groups. The manifestations of anaphylactic shock could be completely inhibited by pre-treatment with cortisone. Halpern and Roux reported that the histamine sensitizing property is characteristic of H. pertussis Phase I and Pittman showed that the protective potency of H. pertussis closely parallels the histamine sensitizing capacity.
In addition to those results, it is indicated from the present experiment that the anaphylactic sensitizing property also may be one of the characteristics essential to H. pertussis Phase I.
Malkiel and Hargis denied the existence of a direct relationship between the histamine sensitizing property and the anaphylactic sensitizing property of H. pertussis. In their studies mice, separately inoculated with horse serum and pertussis vaccine, became markedly susceptible to histamine, but showed hardly any anaphylactic shock. In the present experiment, however, anaphylactic sensitizing property existed only in H. pertussis, but not in H. parapertussis nor in H. bronchisepticus both of which possess the toxin common to H. pertussis. Moreover, this property was entirely resistant to heating at 60ª for 30 minutes, butcompletely destroyed at 80ª for the same periods.
These two results agree with those obtained by Maitland et al. concerning the histamine sensitizing property. Taking into consideration the similarities of both properties, we cannot accept Malkiel and Hargis's conclusion, and assume instead that the two reactions resulting from the inoculation of pertussis vaccine have a close relationship to each other. Further conclusions on this problem, of course, should be drawn only after further separation and purification of these sensitizing factors.