Reactions of Rabbits to Non-Hemolytic Streptococci: Iii. A Study of Modes of Sensitization

Abstract

In previous papers (1, 2) we have described the various types of tissue response of rabbits to inoculation with non-hemolytic streptococci. It was shown that reactions following reinfection were conditioned by the route of the original inoculation: if it had been into the tissues--especially into the skin--the subsequent reaction was that of hypersensitiveness, or hyperergy; if into the blood stream, it was that of immunity. For the sake of completeness two other types of reaction were recorded: that of normal animals, which in the majority of instances was followed by a secondary reaction, and that of cachectic rabbits, in which inoculation resulted in a soft, pale lesion smaller than that of normal animals, and not followed by a secondary reaction.Variability in the response of apparently normal rabbits to inoculation with streptococci is well recognized; and because of this some investigators feel that this species is unsuitable for the study of experimental streptococcus infections. Under ordinary experimental conditions this factor necessitates the introduction of a sufficient number of animals into each experiment to permit of conclusions on a statistical basis. " While such a basis is always requisite in biological research the advantages of having to depend upon it as little as possible are obvious.During our investigations the desirability became more and more evident of ascertaining the best method of rendering a large majority of rabbits satisfactorily hypersensitive to non-hemolytic streptococci in the shortest possible time. This communication gives the details of some of the experiments planned with such an end in view.

Cellular Reactivity Studies to Streptococcal Antigens MIGRATION INHIBITION STUDIES IN PATIENTS WITH STREPTOCOCCAL INFECTIONS AND REHEUMATIC FEVER

“…Apropos of these studies, several intriguing observations concerning the streptococcal hypersensitive state were made. First, repeated small inoculations of heat-killed streptococci were more effective in inducing the hypersensitive state than a single inoculation of living organisms (3). Secondly, extracts of streptococcal cellular structures were more effective in eliciting the hypersensitive reaction than streptococcal extracellular products.…”