Sensitivity of Pertussis Inoculated Mice to Endotoxin

Abstract

The rise and fall of sensitivity to endotoxin in the pertussis inoculated mouse parallels closely the development of histamine and serotonin susceptibility in such animals. Thirteen days after pertussis inoculation, mice possessed an enhanced susceptibility to the lethal effects of Escherichia coli endotoxin as well as to living E. coli organisms. Preliminary injections of sublethal amounts of E. coli or Serratia marcescens endotoxins restore the resistance of pertussis inoculated mice to subsequent challenge with lethal doses of E. coli endotoxin. Injections of E. coli endotoxin, however, do not prevent pertussis inoculated mice from developing an increased susceptibility to histamine or anaphylactic shock. E. coli endotoxin was actually found to potentiate the development of anaphylactic sensitivity in the pertussis inoculated mouse. On the other hand, E. coli endotoxin increased the resistance of pertussis inoculated to subsequent injections of pertussis vaccine. The implications of these findings are discussed.