288 Wassermann Reaction for Diagnosis of Syphilis 



purpose, therefore, of securing the greatest possible number of micro- 

 organisms for the antigenic function, such livers were used. The 

 tissue, having been cut into small fragments, was spread out in 

 Petri or other appropriate dishes and dried, and the fragments 

 rubbed to a fine powder with a mortar and pestle. Such a powder 

 can be kept indefinitely in an exsiccator over calcium chlorid if 

 placed where it is cool and dark. When the powder is to be used, 

 0.5 gm. is extracted either at room temperature or in the ice-box 

 with 25 cc. of 95 per cent, alcohol for twenty-four hours, filtered 

 through paper, and the filtrate used in quantities later to be 

 mentioned. 



Instead of drying the liver tissue, pulverizing, and then extracting 

 it, many investigators now prefer to cut it up, rub it into a uniform 

 paste with a mortar and pestle, and add 5 volumes of 95 per cent, 

 or absolute alcohol, with which the paste is thoroughly macerated 

 and shaken many times or in a shaking machine. The alcohol 

 may then be filtered off, or may be permitted to remain upon the sedi- 

 mented liver tissue remnants, and the clear supernatant fluid 

 pipeted off and diluted, at the time of employment, with the isotonic 

 sodium chlorid solution. When this alcohohc extract is added to 

 the salt solution a turbidity occurs, but this must not be filtered out, 

 as it consists of the lipoids or other substances in the extract that 

 are essential to the test, and the quantity of the cloudy fluid in the 

 final mixtures is so small as not in any way to interfere with the 

 results. The small amount of alcohol in the diluted extract is 

 negligible and has no influence upon the reagents used for the test. 



The mention of the Upoids now brings us to the point where it 

 seems advisable to state that one of the most interesting facts about 

 the Wassermann reaction is that its theoretic basis was founded upon 

 the erroneous assumption that the essential antigenic substance 

 consisted of the whole or fragmented treponemata in the hver ex- 

 tract. The method scarcely began to meet with practical applica- 

 tion, however, before it was discovered that the active antigenic 

 substance was soluble in alcohol, was present in other than syphilitic 

 livers, and could be extracted not only from human tissues, but also 

 from dogs' Hvers and from guinea-pigs' hearts. Porges and Meier, 

 indeed, found that lecithin could play the r61e of syphiUtic- antigen, 

 Leviditi and Yamanouchi place sodium glycocholate, sodium tau- 

 rocholate, protogon, and cholin among those bodies capable of 

 acting as syphilitic antigens, Noguchi goes so far from the original 

 that he regularly employs an extract of the normal guinea-pig's 

 heart as the antigen to be employed in his modification of the test 

 and many now regularly employ human, beef or guinea-pig heart 

 muscle to which cholesterol is added. The method of making chol- 

 esterinized human heart muscle antigen recommended by Weston* 

 is as follows : 



* Jour. Med. Research, 1914, xxx, p. 377. 



