A Comparison of the Toxicity of Various Meningococcus Preparations

[摘要] Various preparations of meningococci were tested by the Shwartzman method. Those containing the products of cell disintegration were found to be much more toxic than the simple filtrate of culture washings, the most toxic of all being a defatted coccus antigen made by extracting the cells with alcohol and ether, and grinding them in a mortar. The reactions obtained with this toxic defatted coccus could be neutralized with homologous immune rabbit serum, but only consistently when the serum was used undiluted and inoculated intravenously in equal volume with the diluted suspension.The antimeningococcus therapeutic horse serum in 1:10 dilution neutralized the toxic effects of all four of the preparations in Shwartzman's skin sensitivity tests.In the mouse protection tests Murray's endotoxin, unfiltered , was more toxic than the other preparations.High dilutions of the antimeningococcus horse serum protected mice against Shwartzman's toxin filtrate, Murray's endotoxin filtrate and the cellular suspension. High dilutions of the serum did not protect against Murray's endotoxin, unfiltered, nor against the defatted coccus.No conclusions have been drawn from these experiments, but the tests indicate that the same toxic substance is present in all of the preparations. The nature of the toxic substance has not been demonstrated by our tests.

[学科分类] 生物科学（综合）