164 



IMMUNITY. THEORIES OF IMMUNITY 



It may be useful here to draw up in tabular form a list of the various 

 antigens and antibodies with which we are mainly interested in that 

 portion of immunity involving infection with vegetable or animal para- 

 sites, and the products of their metabolism or degeneration (Fig. 43). 



ANTIGENS 

 Toxins: 



1. Soluble bacterial toxins (diph- 



theria and tetanus toxins, etc.). 



2. Phyto- (vegetable) toxins (ricin, 



abrin, etc.). 



3. Simple zoo- (animal) toxins; 



(snake, spider, toad venoms). 



4. Complex zootoxins, as snake 



venom, requiring complement 

 for action. 



Enzymes or ferments (rennin, lipase, 

 etc.). 



Precipitogenous substances (soluble ani- 

 mal and vegetable proteins). 



Agglutinogenous substances (bacteria, 

 erythrocytes, etc.). 



Opsonigenous substances (bacterial en- 

 dotoxins or aggressins?). 



Cytoligneous substances: 



1. Vegetable cells (bacteria). 



2. Animal cells (erythrocytes, sper- 



matozoa, kidney tissue, etc.). 



ANTIBODIES 

 Antitoxins : 



1. Antitoxins (diphtheria and 



tetanus antitoxins, etc.). 



2. Anti- (phyto-) toxins (antiricin, 



antiabrin, etc.). 



3. Anti- (zoo) toxins (antivenins). 



4. Antihemolysins, etc. 



Anti-enzymes (antirennin, antilipase, 



etc.). 

 Precipitins. 



Agglutinins. 



Opsonins (acting singly or with comple- 

 ment). ; 

 Cytolysins: r > - 



1. Bacter^ysins. 



2. Hemolysins, spermatolysins, 



nephrolysins, etc. 



