74 IMMUNE SERA. 



Diagnostic Value of Iso-agglutinins and of Isolysins. 



As a result of my own observations, made on 

 patients in the Institute for Infectious Diseases, 

 I attach no particular value to the occurrence of 

 iso-agglulinins in the serum of one patient for the 

 erythrocytes of another. In this procedure, espe- 

 cially in the case of human erythrocytes, there are 

 great sources of error. The erythrocytes of many 

 persons have an inclination to agglutinate on the 

 addition of any human serum, so that even the serum 

 of the same person will agglutinate these red cells. 

 In my opinion, therefore, it is unwise to attach 

 much importance to the occurrence of iso-agglutinins; 

 we should rather look for the occurrence of isolysins 

 in the different diseases. In the isolysins the sources 

 of error just mentioned do not obtain. 



E. Neisser, Doring, and Lacqueer were able to 

 show that in cases of uraemia substances appeared 

 in the serum which acted very much like auto-anti- 

 complements. The number of the observed cases, 

 however, is too small to draw definite conclusions. 



Immunization against Other Substances. For com- 

 pleteness' sake it may be mentioned that it has 

 been possible to immunize against a great vari- 

 ety of ferments; thus against emulsin (Hilde- 

 brandt), certain ferments in bacteria (v. Dungern), 

 rennet (Morgenroth and Briot), and against fibrin 

 ferment (Bordet and Gengou). 



With all these sera the results obtained experi- 

 mentally have thus far been applied clinically to too 



