The complement fixation test in syphilis, commonly known as the Wassermann test.

  • Great Britain. Ministry of Health
Date:
1920
Catalogue details

Licence: Public Domain Mark

Credit: The complement fixation test in syphilis, commonly known as the Wassermann test. Source: Wellcome Collection.

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    tissue. After extraction, the material is filtered, and the filtrate evaporated to dryness by the aid of an electric fan. The residue is taken up with ether, and the solu- tion thus obtained is allowed to stand overnight in a cool place. In the morning the supernatant ether will be found perfectly clear, while the insoluble portion of the residue has settled to the bottom of the receptacle.’ The clear ethereal portion is decanted off and evaporated toa small quantity and mixed with 10 volumes of pure acetone. The precipitate which forms is allowed to settle, and the supernatant quid poured off. The pre- cipitate is light brown in colonr, and forms the material from which the antigen [suspension] is made, 0°3 gram of this acetone-insoluble fraction being dissolved in 1 ce. of ether and then mixed with 9 c.c. of methyl alcohol.” We have found that ox heart forms an equally satisfactory source of acetone-insoluble lipoid prepared as above. We have not yet sufficient data to determine the limits within which preparations from different ox hearts may vary. It has been shown by Noguchi that the acetone-insoluble fraction of the alcoholic extract contains the essential con- stituents of the Wassermann antigen. Moreover, treatment with acetone removes various undesirable substances, such as soaps and fats, and the final product is less anticomplementary than many crude alcoholic extracts. This attempt by Noguchi to obtain the antigenic substances in a purer state is an important step and is a subject worthy of further attention by bio-chemists. : | But the Noguchi extract alone sometimes fails to detect syphilitic sera which give a definite positive reaction with simple alcoholic heart extracts, with or without cholesterin. It is evident that, to obtain the most delicate reactions, some proportion of the acetone-soluble lipoid (cholesterin) must be present in addition. Is it possible to combine the adjuvant action of the latter with the pure specific action of the former ? (5) Standardisation of Antigen.—lIf our conception of the mode of action of cholesterin is correct, it should be possible to adjust the proportion of cholesterin in the total lipoid contents so that the intensifying action of the former is obtained, while its precipitating effect on the serum globulins, however unstable. is reduced to a minimum. Such an antigen would be both safe and powerful. But in attempting this with crude organ- extract one is met with certain difficulties. In the first place such extracts often contain anticomplementary substances which apparently take no part, or at any rate no essential part, in the specific reaction yet complicate this by their independent inhibitory action on complement. Secondly, they vary very much in the amount of cholesterin they contain and some already contain an excessive amount; the latter condition appears especially common in extracts from guinea-pigs’ hearts.
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