ANTI-ENZYME IMMUNITY 185 



the inhibitory and the proteolytic powers of ascarase ran parallel. It 

 inhibited trypsin and pepsin to the same degree, but had no effect on 

 papain. 



Northrop (1933) found that crystalline edestin adsorbs pepsin from 

 a solution, removing it completely at pH 4.0. The pepsin content of 

 "edestin-pepsin" complex was found to be as high as 50 per cent. In 

 this form the pepsin activity was not arrested. A suspension of "edestin- 

 pepsin" complex on standing at room temperature gradually dissolved, 

 eventually completely, so that the final solution consisted of the 

 digested edestin containing the original quantity of pepsin. 



A combination between crystalline d-ribonuclease and tobacco 

 mosaic virus resulting in the reversible inactivation of the virus was 

 reported by Loring (1942). A virus-enzyme complex formed long 

 fibre-like particles, which on analysis proved to contain about 14 

 per cent d-ribonuclease. This complex was dissociable completely, 

 liberating the virus in fully active form. The dissociation took place 

 by diluting the solution of the complex from 1 to 500 to 1 to 1000 

 times. The liberation of virus from the virus-enzyme complex was 

 achieved also by sedimenting it at high speed and redissolving the 

 pellets. On repeating this process a few times 92 per cent of the virus 

 was recovered. 



2. The Question of Non-Specific Adsorption of Toxins 

 or Enzymes on Coexisting Protein-Anti-Protein 

 Precipitates 



The diminution of the activity of enzymes in the presence of ho- 

 mologous immune sera was assumed by Bayliss to be due also to non- 

 specific adsorptions on extraneous protein impurities in the form of 

 antigen-antibody precipitates. This question of non-specific adsorption 

 as the cause of serological reactions has often been raised since the 

 early beginnings of the science of immunology and has been critically 

 considered in numerous studies. However, since there still seems to be 

 an element of doubt in the mind of many workers regarding the exist- 

 ence of immune anti-enzymes, it is necessary that the available data 

 regarding this question be further analyzed. 



At first a few examples of adsorptions of enzymes on materials, 

 such as were mentioned by Bayliss, will be given. There is no doubt 



