36 IMMUNE SERA 



possibly prove disastrous in human homologous trans- 

 fusion. For this reason it is now common practice to 

 always precede homologous transfusion by an examina- 

 tion of the blood of both donor and recipient. A brief 

 outline of these tests is given in the appendix. 



Purpose of Agglutination. It is not yet clear 

 what the purpose, if any, of ths agglutinating 

 function is. Gruber, the first to thoroughly study 

 and appreciate the bacterial agglutinins, assumes 

 that the process injures the affected cell, preparing 

 it for solution and destruction. After numerous 

 experiments I have not been able to convince 

 myself of any damaging influence of the agglutinins 

 on the affected cell, be this blood cell or bacterium, 

 and the observations of other authors confirm this 

 opinion. Agglutinated bacteria are capable of 

 living and of reproduction, and agglutinated red 

 blood cells are no more fragile or easier to destroy 

 than normal, non-agglutinated cells. Neither can 

 anything be discovered microscopically which would 

 indicate any injury to their structure. 



One thing is certain: that the agglutinins are in 

 no way related to the lysins found in serum, and 

 so of course are not identical with these. The 

 simultaneous occurrence in a serum of immune 

 bodies, interbodies, complements, and agglutinins 

 is an entirely independent phenomenon which is 

 in no way regular. There are sera which dissolve 

 certain cells without agglutinating them, and others 

 which agglutinate cells without dissolving them. 



