RELATION OF SKIN TO NONSPECIFIC RESISTANCE 133 



increase in the antiferment titer, alterations in the permeability of the 

 vessels, and temporary depression of the irritability of the vasomotor 

 system and central nervous system which lasts for a period of a week 

 or so after the injection. 



The converse of this clinical observation has to deal with the 

 reactivation of skin foci by nonspecific injections after they have 

 undergone involution. Thus it has been observed that old tuberculin 

 papules will become active when a subcutaneous injection of tuberculin 

 is given in some remote area of the body, when milk is injected or 

 colloidal metals injected intravenously. To what degree elements of 

 specificity enter into this reactivation is by no means determined. 

 Munzer observed that when partial antigens (Dyche-Much) were 

 injected they would often reactivate old intracutaneous tuberculin 

 papules while milk injections did not have this effect. 



Closely related is the effect of the iodids and other chemical 

 agents which on administration activate involuting papules. If intra- 

 cutaneous skin tests are made with luetin or tuberculin during active 

 iodization of the patient, the skin reaction, instead of being limited to 

 mere papule formation, usually goes on to the complete pustule stage 

 of inflammation. Now the iodids act, as do the related chemical 

 agents, either by lowering the antiferment titer (Jobling and Petersen) 

 or by nonspecifically stimulating the tissues (and so increasing the 

 amount of protease and other enzymes in the tissue fluids) or finally 

 because of their effect in hastening the rapidity of diffusion of other 

 salts (and colloids) in colloidal systems. The end result is of course 

 the same digestive processes are hastened. The two other conditions 

 leukemia and thyroid feeding in which the skin reactivity is in- 

 creased are associated with a diminution of the antiferment titer and 

 an increased enzyme activity.* 



When, therefore, involuting papules flare up under nonspecific 

 injections we must consider the possibility that the following changes 

 may form the basis of the inflammatory reaction. With the height of 

 the nonspecific reaction (negative phase digestion) a considerable 

 amount of protease is mobilized locally and generally and the anti- 

 ferment is diminished. If in an involuting area a certain amount of 

 undigested protein material is still present, digestion will commence, 

 protein split products will be liberated at the focus and the lesion will 

 again flare up that is, we will witness a focal reaction. The local 

 cells, it is to be remembered, are particularly reactive in such a con- 

 dition. 



When the patient is iodized and an intracutaneous test made we 

 seem to deal simply with a condition where digestion has been able 



* The fact that iodids may have no direct effect on tissue autolysis in vitro 

 as Albrecht has recently demonstrated has no direct bearing on the point at 

 issue which in vivo concerns rather the mobilization of protease from normal 

 tissues and their effect on tissues that have undergone degenerative change. 



