250 FERMENTS AND ANTIFERMENTS 



Abderhalden has found ferments for the tubercle bacillus in the blood- 

 serum of tuberculous persons, and they have also been found in the blood- 

 serum of syphilitics for the Treponema pallidum, either in pure culture 

 or in organs containing large numbers of the parasites. 



Although these protective ferments are in general similar to the cyto- 

 lysins or antibodies produced during bacterial and protozoan infections 

 capable of lysing or digesting their antigens, their exact nature and rela- 

 tion to the cytolysins have not been determined. From the evidence 

 at hand it would appear that the ferment-like cytolysin is specifically 

 directed against the toxic portion of a bacterial cell, and the proteolytic 

 ferment against the bacterial cell itself. Recent work by Pearce and 

 Williams 1 would seem to indicate that the cytolysins and protective 

 ferments are separate substances, but considerable additional experi- 

 mental investigation is required to clear up the point. 



Although recent investigations would tend to show that these pro- 

 teolytic ferments are not so specific as Abderhalden believes, the subject 

 is one of the greatest importance, and its elucidation may possibly throw 

 much light upon the nature of immune bodies in general. The technic, 

 specificity, and practical value of the methods devised by Abderhalden 

 for detecting the proteolytic ferments in the serum of cases of pregnancy, 

 cancer, etc., are considered in a later portion of this chapter. 



FERMENT REACTIONS 

 ANTITRYPSIN TEST 



Bergmann and Meyer 2 have devised a test for estimating the titer 

 of antitrypsin that possesses value in determining the presence of tryp- 

 tic ferment in the blood-serum and in the intestinal and stomach con- 

 tents. The test may also prove of value in making a functional study 

 of the pancreas. At present it is regarded by some as an aid to the 

 diagnosis of cancer, and it may also be of service in establishing the 

 diagnosis and prognosis of suppurative processes. 



Solution of Trypsin. This is made by dissolving 0.5 gm. of pure 

 trypsin (Griibler) in 50 c.c. of NaCl solution and adding 0.5 c.c. of normal 

 soda solution; make up to 500 c.c. with physiologic salt solution. 



Casein Solution. Dissolve one gram of pure casein in 100 c.c. of 

 sodium hydroxid solution with the aid of gentle heat. Neutralize to 

 litmus with ^ hydrochloric acid solution and dilute with physiologic 



1 Jour. Infect. Dis., 1914, xiv, 351. 2 Berl. klin. Wochenschr., 1908, No. 37. 



