The preparation and some properties of purified diphtheria toxoid / by Arthur Frederick Watson and Elsie Langstaff.

  • Watson, A. F.
Date:
[1926?]
Catalogue details

Licence: In copyright

Credit: The preparation and some properties of purified diphtheria toxoid / by Arthur Frederick Watson and Elsie Langstaff. Source: Wellcome Collection.

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    partially overcome. Larson and Eder [1926] also support the use of simplified immunising preparations and claim that toxic culture filtrates which have been detoxified by sodium ricinoleate are fully equal, and in many respects superior, to toxin-antitoxin mixtures as immunising agents. There would seem to be two urgent problems awaiting solution in this field of immuno-chemical research. The first problem is to convince ourselves that under no circumstances are the toxin-toxoid reactions reversible ana to determine the relative values of such detoxifying agents as formaldehyde and the salts of ricinoleic acid, etc. The work of Grlenny and his colleagues in England, Ramon in France, and Park and his co-workers in America have failed up to the present to expose any sign of such a reversal in the case of culture filtrates detoxified with formaldehyde but information on the nature of the action of the formaldehyde is lacking. Our knowledge of the action of salts of ricinoleic acid on toxin is confined to the work of Larson and his co- workers and no extended use of their toxoids as immunising agents has yet been possible. The second problem awaiting solution is to purify these toxoid antigens. The active principle of culture filtrates is probably Confined to a very small fraction of the total material and as shown later, it is possibly associated with less than 1 % of the nitrogenous material in the culture filtrates. If this is so, the purification of the antigens should do much to eliminate the non¬ specific reactions which as Park and his colleagues state preclude the proper use of atoxic preparations for the immunisation of human beings. Further, investigation of the constitution of antigens and the chemical processes of immunity may be facilitated if comparatively pure antigens are substituted for the highly impure culture filtrates which at present form the basis of our attack on the various problems. Research in this field has been facilitated during the past few years by the work of Ramon [1922], whose flocculation test for assaying the strength of diphtheria toxin and antitoxin has received almost universal recognition. The present work is essentially a development of that of Watson and Wallace [1924, 1, 2] on the purification of culture filtrates. Some of the properties of purified toxin were described but at the time the only well-established methods of testing the various fractions were by the use of animals, and progress was necessarily slow. This work has recently been confirmed by Moloney and Weld in Canada [1925]. The present paper consists of a brief survey of the method of purification of culture filtrates containing toxins partially or completely converted into toxoids by formalin together with a discussion of some of the properties of the purified substance. The technique of Ramon was employed for testing the value of the fractions and has thrown light on many of the facts which were described in the previous paper [Watson and Wallace, 1924, 2] and for which at the time no explanation was forthcoming.