98 IMMUNE SERA 



the isolysins, like the hsemolysins, consist of an 

 immune body and a complement of the normal 

 serum. The experiments undertaken by these 

 authors were made on thirteen goats, and the sur- 

 prising fact developed that the thirteen resulting 

 isolysins were all different. For example, the iso- 

 haemolytic serum of one goat dissolved the red cells 

 of goats A and B\ that of a second goat those of 

 C and D ; of- a third those of A and D, but not of C, 

 and so on. If now they produced antiisolysins by 

 injecting animals with these isolysins, they found 

 that these antiisolysins were specific; i.e., the anti- 

 isolysin of A would inhibit the action only of iso- 

 lysin of A, but not of C, etc. These results are of 

 the highest clinical interest, for they show a differ- 

 ence in similar cells of the same species, something 

 that had never before been suspected. In the above, 

 the blood cells of species A must have a different bi- 

 ological constitution than those of species C, etc. 



Moss finds that isolysins occur in about 2 5 % of adult 

 human individuals, and that the relative frequency is 

 the same in health and disease, so that the presence 

 of isolysins has no diagnostic significance. The sub- 

 ject has recently acquired importance because of the 

 revival of homologous transfusion, and it is customary 

 now to always test the blood of both donor and re- 

 cipient prior to carrying out such a transfusion. The 

 technique of the test is described in the appendix. 



The fact that after injections of large amounts of 



