The advance of bacteriological science in the diagnosis and prevention of disease : being the inaugural lecture on the foundation of the new Chair of Pathology and Bacteriology, Mason University College, delivered October 9, 1899 / by R.F.C. Leith.

  • Leith, R. F. C. (Robert Fraser Calder)
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: The advance of bacteriological science in the diagnosis and prevention of disease : being the inaugural lecture on the foundation of the new Chair of Pathology and Bacteriology, Mason University College, delivered October 9, 1899 / by R.F.C. Leith. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    publication of Ehrlich's work last year. It led to an earnest revision of the whole question and the balance of evidence and opinion now leans strongly to the other side. Toxin and anti- toxin can be made to combine in a test tube outside the body much in the same way as they do within it, and their various reactions point clearly to the nature of their union being in all probability a chemical one. We can even go further and suggest with much show of reason that their union is similar to that which prevails in the formation of a well known class of chemical substances, viz. double salts. Many of their reactions are in accord with those which regulate the union of an acid and a base, but others do not harmonise with this view, tending rather to support the double salt nature of the process. Ehrlich suggests that the toxine molecule consists of two atom groups, the one, haptophorous, having the property of binding the toxine and antitoxine together; and the other, toxophorous, carrying all the toxic properties. Vide Fig. 5. The former is a relatively simple and stable group, while the latter is complex and unstable, readily breaking down into non-toxic substances which still remain linked to the haptophorous group, thus preserving the integrity of the toxine molecule, now, however, no longer toxic. He proposes the name of toxoids for these non- toxic substances. It is by means of the haptophorous group that the toxine molecule becomes united to the anti-toxine, and hence it will require the same amount of the latter to neutralise it even if it have previously lost all its toxic power. It is possible further that bacteria may sometimes produce, de novo, similar toxoid molecules, and not only through the degeneration of a previously toxic group. Ehrlich, indeed, asserts that he has found evidence of this in diphtheria, and proposes the name of toxones for such naturally produced toxoids. We have already explained that when toxines are injected into an animal they lead to the production of anti-toxins within its tissues which may result in their neutralisation. This result will therefore follow whether the toxine molecule preserves its toxic group unchanged or has become degenerated into harmless toxoids.
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