244 PHARMACEUTICAL BACTERIOLOGY 



while the haptophore group is not destroyed, retaining the power of com- 

 bining with the receptor group of the living cell. The toxophore group is 

 not necessarily simple. It may comprise two or more different groups. 

 Snake poison contains two toxophore groups, one agglutinating red blood 

 cells, the other causing its general toxicity. Diphtheria toxin also has two 

 toxophore groups, the one causing the acute symptoms and the other, the 

 toxones with a long incubation, causing the later paralyses and cachexias. 



The nature of immunity to these antigens is conceived as follows : The 

 haptophore group is bound to the cell receptor because of a specific affinity. 

 As a result this particular side chain or receptor is lost to the living cell and, 

 following Weigert's law of supercompensation in regeneration, the cell 

 replaces this loss by producing many more receptor groups than were pre- 

 viously present. As in the callus following a fracture there is an over- 

 production. In this way such a large number of receptors of one type are 

 produced that they become excessive and the cell thrusts them off into the 

 blood and into the fluids of the body. Here they constitute the specific 

 antibodies and, because of their specific affinity, unite with the haptophore 

 group of toxins and prevent their reaching the cell which they thus protect. 



Therefore, in antitoxic immunity there are three stages: First, the 

 chemical union of the haptophore group of antigen to the receptor group of 

 the protoplasm molecule; second, the overproduction and liberation of 

 these receptors following this binding;' and third, the union of these free 

 receptors or antibodies with free toxin haptophore groups before these can 

 reach the cells to injure them by the action of their toxophore groups. The 

 antigens that are known with their respective antibodies as given by 

 Hektoen are : 



Antigens Products of Immunization 



Toxins Antitoxins 



Ferments Antiferments 



Precipitinogens Precipitins 



Agglutinogens . Agglutinins 



Opsonogens Opsonins 



Lysogens Amboceptors or lysins 



Antitoxins Antiantitoxins 



Agglutinins Antiagglutinins 



Complements Anticomplements 



Opsonins Antiopsonins 



Amboceptors Antiamboceptors 



Precipitins Antiprecipitins 



These antibodies all result from the overproduction of simple receptors, 

 but the protoplasm of cells may form still other cell receptors which are 

 much more complicated and subserve the absorption of more complicated 

 and complex albuminous molecules than those of toxins. 



