Immunological Studies in Tuberculosis

Abstract

Summary Five series of experiments with guinea pigs sensitized with dead tubercle bacilli are reported, in which tuberculin hypersensitiveness was induced with dead tubercle bacilli. During the allergic state inoculations of living tubercle bacilli were made, with the use of approximately the same number of normal control animals. The sensitized animals outlived the controls an average of 46 days. The amount of macroscopic disease at autopsy in the former was much less extensive than in the latter, confirming the belief that dead tubercle bacilli can induce some degree of protection. A small series of guinea pigs was sensitized with Dreyer’s defatted tubercle bacilli. We produced only a mild skin hypersensitiveness and even that not uniformly. No appreciable resistance could be observed in these animals. The average duration of life was approximately the same as that of the control animals.