260 FERMENTS AND ANTIFERMENTS 



tissue and brain cortex. In general paresis reactions were obtained with 

 brain cortex and liver, also at times with thyroid gland, reproductive 

 glands, and more rarely with kidney. 



Abderhalden has found ferments for the tubercle bacilli 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; 

 Smith 1 has found a remarkable specificity of the ferments produced 

 in rabbits following immunization with typhoid and paratyphoid bacilli 

 and cocci. 



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 2 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. 



Mechanism of the Abderhalden Reaction. Aside from the probable 

 clinical value of the methods devised by Abderhalden in the serum diag- 

 nosis of pregnancy and various pathologic conditions, as malignancy, 

 tuberculosis, lesions of the nervous system and ductless glands, most 

 interest concerns the question of the specificity of the ferments or anti- 

 bodies concerned and the mechanism of their action. 



While Abderhalden and many of his pupils have claimed a high degree 

 of specificity for the "protective ferments" and his pregnancy reaction, 

 claiming from the beginning that errors of technic were largely respon- 

 sible for the failure of others to obtain satisfactory results, the dialysis 

 test as now conducted is not especially difficult, and sufficient work has 

 been done by other investigators who have followed Abderhalden's 

 technic with great care and exactness to give warrant to the claim that 

 other factors aside from those purely technical may be responsible for 

 the divergent and non-specific results obtained. 



As previously stated, Abderhalden bases his theory concerning the 

 "protective ferments" upon the specific digestion of a substrat by 

 specific ferments, claiming that these ferments are separate and dis- 



1 Jour. Infect. Dis., 1916, 18, 14 2 Jour. Infect. Dis., 1914, xiv, 351. 



