Improved Method of Preparing Bacillus Typhosus Toxic Substances Necessary for Local Skin Reactivity.

Abstract

ConclusionIt is possible to obtain highly potent skin preparatory and reacting factors in filtrates of washings of 20-22 hour old Bacillus typhosus cultures on plain agar. Under these conditions there is avoided much of the extraneous material present in tryptic digest broth previously employed, as well as much of the bacterial autolysis occurring in the older method. This would indicate that the skin preparatory and reacting factors are bacterial soluble substances, the production of which is independent of massive cell destruction.The filtrates prepared in this manner produce negligible primary effect upon the skin (erythema, swelling), notwithstanding their high skin preparatory potency. This is in agreement with the view previously expressed1,25 that the skin preparatory potency of a given filtrate bears no relation to its primary effect on the skin.It is of considerable interest to note that there exists a distinct reciprocal quantitative relationship between the skin and intravenous (loses. This obs...