138 



Immunity 



The essence of Ehrlich's theory is tersely expressed by 

 Behring: "The same substance which when incorporated 

 in the cells of the living body, is the prerequisite and con- 

 dition for an intoxication, becomes the means of cure when 

 it exists in the circulating blood." 



Figs. 22 and 23. Show the regeneration of the cell-haptophores or 

 receptors to compensate for the loss of those thrown out of service. 



Fig. 24. Shows the number 

 of haptophores regenerated by 

 the cell becoming excessive, they 

 are thrown off into the tissue 

 juice. 



Fig. 25. Explains what anti- 

 toxins are and how they are 

 formed. The liberated receptors 

 in the tissue juice and in the 

 blood, possess identical combin- 

 ing affinities with those upon the 

 cell, and meeting the adapted 

 haptophorous elements in the 

 blood, combine with them, thus 

 keeping them from the cells. 



Continuing the quotations from Ehrlich's Croonian Lec- 

 ture, we find: "In the first place, our theory affords an 

 explanation of the specific nature of the antitoxins, that 

 tetanus antitoxin is only caused to be produced by tetanus 

 toxin, and diphtheria antitoxin through diphtheria toxin. 



