Remarks upon the pneumotoxin / by Allan MacFadyen, M.D. (from the Bacteriological Department, King's College.).

  • Macfayden, Allan, 1860-1907
Date:
[1906?]
Catalogue details

Licence: In copyright

Credit: Remarks upon the pneumotoxin / by Allan MacFadyen, M.D. (from the Bacteriological Department, King's College.). Source: Wellcome Collection.

    2/4 (page 2)
    poisons as specific, and used them for the preparation of an antitoxic serum. The toxic and antitoxic effects were of a feeble character, and large quantities of the filtered broth cultures were necessary to produce an active immunization of animals. Foa and Searbone2 and Scabia3 conducted experiments on similar lines, but these did not yield any more striking results. Pane’s4 investigations upon a soluble poison were practically negative, and led him to ascribe little importance to the action of a poison in pneumonia. Mennes,5 working with highly virulent strains of the pneumococcus, found that the filtered cultures possessed little toxicity. It was only in large doses that filtered or heated cultures produced a lethal effect. Broth cultures, which had been heated to 62° C. for twenty minutes, caused on injection fever, loss in weight, and at times diarrhoea, but the results were inconstant. Rabbits treated with the toxins were in some instances resistant to a fatal dose of the pneumococcus. Mennes also immunized the goat and horse with heated, then unheated, broth cultures and the blood of infected rabbits. In the case of the horse, its serum protected against the pneumococcus and the broth toxin, which produced fever and loss in weight. Mennes does not appear to have worked with an acutely lethal toxin, and this detracts from the value of his results. Isaeff6 also found that sterilized cultures in general possessed feeble toxicity, and were not fatal in doses equivalent to 3£ per cent, of the animal’s weight. On the other hand, the blood of infected rabbits yielded a filtrate toxic on intravenous injection, and sor tetimes lethal in doses equivalent to 1 per cent, of the body weight—that is, about 10 c.cm. per kilogram of rabbit. A dose of 10 c.cm. rendered rabbits immune to the pneumococcus but not to the toxin. Sterilized broth and serum cultures in amounts of 10 to 50 c.cm. pro¬ duced a rise in temperature and loss in weight. Isaeff concludes that “ one cannot admit the existence of an antitoxic property of the blood in animals vaccinated against the pneumococcus.” The toxins obtained by Isaeff were, however, not sufficiently powerful to justify the conclusion drawn from his experiments with them. Carnot and Fournier7 describe toxic dialysates obtained from cultures of the pneumococcus after concentration by drying in vacuo, and by precipitation with phosphate of lime. The antipneumococcic serums prepared by Pane, Wash- bourn,8 and Romer9 by the injection of various strains of pneumococci protected animals against multiple lethal doses of virulent pneumococci. No antitoxic action has been claimed for these serums. The efforts to obtain potent soluble poisons from fluid cultures of the pneumococcus have not proved successful, nor have the soluble poisons described shown much value as immunizing agents. None of the experiments in this direction, it may be added, furnishes any conclusive proof