THE PROTEOLYTIC MECHANISM IN OPERATION 103 



great value in teaching the clinician that he must not depend 

 too fully on his clinical thermometer as a guide to the virulence 

 of disease. 



As to pharmaceutical agents calculated to stimulate the activ- 

 ities of the cytogenic system, mention was made in the original 

 presentation of the Proteomorphic thesis, of secretin, of thyroid 

 extract, of powdered spleen, and of bone marrow. Doubtless 

 these agents have a measure of utility, but in the light of recent 

 experience they assume an altogether subordinate role. The 

 parenteral injection of non-toxic proteins has been shown to 

 offer therapeutic possibilities scarcely more than adumbrated by 

 any stimuli to the cytogenic apparatus hitherto known. These 

 possibilities are forecast in the general treatment of the theory 

 of antigenic response in the original presentation of the Pro- 

 teomorphic theory. 



The details of their application, through the development of 

 Proteal therapy, will form the subject matter of most of the 

 succeeding chapters of this book. 



SERUMS, VACCINES, AND DIRECT CYTO-THERAPY 



Of specific serum and vaccine therapy in general I shall speak 

 only in the most general way, although reference to the non- 

 specific elements always necessarily involved will be made in 

 another connection. By way of anticipation, however, there 

 are one or two aspects of the subject that may advantageously 

 be given brief consideration here, from the standpoint of the 

 Proteomorphic theory. 



Consider, for example, the observation of Dr. W. H. Park, to 

 the effect that when a horse having a strongly antitoxic blood is 

 injected intravenously with a definite amount of toxin, very 

 little production of antitoxin takes place, because the toxin is 

 neutralized by the antitoxin in the blood, whereas the same 

 amount injected in scattered spots subcutaneously will produce a 

 large amount of antitoxin. Dr. Park argues, logically enough, 

 that such portions of the subcutaneously injected toxin as come 

 into the blood stream will meet the same fate as that injected 

 intravenously. He concluded, therefore, that some or all of the 

 cells in the area in the subcutaneous tissues that the toxin reaches 

 must take part in producing antitoxin. 



This conclusion is obviously in harmony with the Proteomor- 

 phic theory, which postulates that body-cells of many types may 

 on occasion respond to the invasion of toxins of the polypeptid 

 order of chemical complexity. It should be recalled, however, 

 that white and red corpuscles are everywhere within reach, in 

 more or less static capillaries and tissue fluids, and that their 



