Immunologically Induced and Elicited Local Resistance to Staphylococcus aureus.

Allergy characterized by delayed hypersensitivity was induced in populations of mice by injection, respectively, of Staphylococcus aureus and of tubercle bacilli. Eliciting doses of staphylococcal antigen or of old tuberculin antigen were injected subcutaneously into the nape of the neck of samples of these mice. A challenge dose of S. aureus was injected into the site of the eliciting injection, and the subsequent survival curves of the infecting staphylococci were determined by plate counts. Survival of the challenge staphylococci was significantly reduced only when the eliciting antigen was homologous with the inducing antigen. Thus induction and elicitation were specific, but the local resistance was nonspecifically effective against staphylococci.