526 THE RELATION OF COLLOIDS AND LIPOIDS TO IMMUNITY 



The following method, employed by Seifert, is much simpler, but is 

 open to the error on account of using the antigen and serum in too con- 

 centrated a state. In a small test-tube place 0.1 c.c. of a 1 : 10 solution 

 of the serum in normal salt solution, and add 0.1 c.c. of an alcoholic 

 extract of syphilitic liver. To this slowly add 1 c.c. of decinormal 

 sulphuric acid and 1 c.c. of a solution of barium hydroxid of the exact 

 concentration needed to neutralize the sulphuric acid solution. On the 

 addition of the drop of the phenolphthalein solution the fluid turns red 

 when the serum is from a syphilitic, whereas no change in tint occurs 

 with non-syphilitic serum. 



Practical Value. The reaction appears to be of considerable value 

 in the diagnosis of syphilis. With serums and antigen in proper dilu- 

 tions, the results closely parallel those secured by the Wassermann reac- 

 tion. Keidel and Hurwitz report positive reactions with luetic serums 

 in about 75 per cent of their cases. The reaction was found highly 

 specific in that syphilitic extracts gave negative reactions with serums 

 of non-syphilitic persons and patients suffering from malignant disease. 

 Extracts of normal fetal liver and beef heart gave negative reactions 

 with serums of syphilitic persons. 



Positive reactions have also been found in malignant disease, as with 

 the antigens of carcinoma and sarcoma. Keidel and Hurwitz obtained 

 16 positive reactions in a series of 24 serums of persons suffering with 

 definite or suspected malignant disease. Burmeister did not find the 

 reaction of value in cancer. 



The epiphanin reaction has also been used in the diagnosis of preg- 

 nancy, but sufficient work has not been done to render an expression as 

 to its merits of value at this time. 



THE MIOSTAGMIN REACTION 



Among the very large number of immunity reactions employed in 

 attempts to secure a diagnostic test for cancer, the "miostagmin reac- 

 tion" of Ascoli and Izar 1 is the only one thus far devised that claims 

 the serious attention of the clinician. 



Principles. This reaction is founded on the fact, noted by Ascoli, 

 that by the mixing of an antigen and its corresponding antibody there 

 results a reduction of the surface tension of the liquid containing these, 

 which may be demonstrated by counting the number of drops of the 

 fluid in a given volume (usually 1 c.c.), under constant conditions. 

 Normal serum diluted with salt solution is first tested, and the number of 



1 Munch, med. Wochenschr., 1910, 57, 62, 182, and 403. 



