SPECIFICITY OF CYTOTOXINS. 293 



might be learned. The use of an antipancreatic 

 serum might throw some light on the nature of 

 diabetes. Therapeutic possibilities also suggested 

 themselves. One might be able by means of artifi- 

 cial anticytotoxic serums to counteract cytotoxins 

 which , were being formed pathologically in the 

 body. Or, by injecting small amounts of a cyto- 

 toxin, perhaps one could stimulate to a renewed 

 production of the homologous cells ; small doses of 

 a hemolytic serum might be useful in combating 

 anemias. Or small amounts of leucotoxic serum 

 might cause an increase in the number of leuco- 

 cytes, and thereby an increased resistance to infec- 

 tion. Perhaps autocytotoxins are formed in some 

 such manner as the following: An extraneous 

 toxic substance causes the destruction of a few 

 kidney cells, the constituents of the latter reach 

 the circulation and stimulate other organs to the 

 formation of autonephrotoxic amboceptors, which 

 then assist in the destruction of more renal tissue, 

 with the result that a vicious cycle is set up. 



In spite of so many theoretical values, the study 

 of cvtotoxic serums has not yielded the results 

 which were anticipated, perhaps chiefly because of 

 their lack of specificity (Pearce and others). Al- 

 though the cells of the different organs differ wide- 

 ly in their morphology and function, there are no 

 doubt certain chemical constituents (receptors) 

 which they possess in common. Of this we have 

 experimental proof from the fact that immuniza- 

 tion with one type of cell yields a serum which is 

 toxic for the cells of various organs. It is difficult 

 or impossible to injure one organ to the exclusion 

 of all others by means of a cytotoxin. One may 

 attempt to purify a cytotoxic serum through ab- 



