ANTI-ENZYME IMMUNITY 187 



form. Klopstock and Neter (1933) reported that tannin detoxifies 

 cohra venom and ricin in vivo, as well as their hemolytic effect in vitro. 

 However, these inhibitions by tannin were reversible by simple dilu- 

 tion of the detoxified reaction mixtures. It is apparent from these 

 studies that the inhibitory action of such substances is easily reversible, 

 and has nothing in common with the inhibitions brought about by 

 immune bodies. 



Liiers and Albrecht (1926) in a study on immune anti-amylase, in- 

 vestigated this particular question of non-specific adsorption of an 

 enzyme on a coexisting antigen-antibody precipitate to meet this specific 

 objection of Bayliss. The amylase activity in the presence of egg 

 albumin-anti-egg-albumin precipitate showed no decrease. 



Since data of sufl&cient scope regarding the non-specific adsorbability 

 of enzymes in an antigen-antibody reaction environment are not avail- 

 able, we will discuss as a means of comparison the data regarding 

 the non-specific adsorbability of toxins on serological precipitates. Such 

 a comparison between toxins and enzymes is justified on the basis of 

 the resemblances of their physico-chemical properties, as well as the 

 enzymic properties manifested by certain toxins. These resemblances 

 have been observed for many years (Wells, 1929). The same difficulty 

 is encountered in isolating toxins and enzymes; both are approximately 

 of similar molecular dimensions and are non-dialyzable through animal 

 or other membranes; they pass through porcelain filters; they possess 

 similar adsorption properties; neither will stand boiling and most forms 

 are destroyed at 80° instantly or in a short time; left standing in solu- 

 tion for some time they gradually lose their specific properties, the toxin 

 becoming toxoid and the enzyme a fermentoid. 



Besides the above physico-chemical resemblances between the toxins 

 and enzymes they exercise two other properties which bring them 

 closer. The first is the high degree of activity of toxins which compare 

 favorably with those of enzymes. The second is the fact that toxins 

 often show enzyme activities, whereas certain enzymes show toxic 

 activities. Eaton (1936) found that tetanus toxin of certain purity is 

 fatal in a quantity of 0.4 microgram per kgm. body weight of a guinea 

 pig. Sommer (1937) found that 0.2 microgram of botulinus toxin per 

 kgm. of the body weight of mouse is fatal. Eaton (1936) and Pappen- 

 heimer (1937) found that 0.4 microgram of diphtheria toxin per kgm. 

 body weight of guinea pig is fatal. 



