1909.] 



HcBm-agglutinins, etc., in the Blood. 



75 



Experiment was repeated after the same serum had been saturated in the 

 maimer indicated for — 



I hour at 37° C, 50 cells = 146 bacilli. 

 1 hour at 37° C, 50 cells = 100 bacilli. 



In this instance the immune serum (A) was found to be powerfully 

 haimolytic on immune red cells (B), but on the other hand the same red cells 

 were hiemolysed by another sample of immune serum, but in this instance 

 there was no marked reduction in phagocytosis after saturation for a quarter 

 of an hour at 87° C. 



In a paper published in the ' Proceedings of the Eoyal Society,'* by 

 Mr. Shattock in conjunction with one of us (L. S. D.), it was shown that 

 leucocytes obtained from different sources may vary in their phagocytic value 

 like the serum. From numerous observations conducted along the same 

 lines by us a large amount of confirmatory evidence has been collected. 



A few instances may be cited to illustrate these remarks : — 



(rt) Normal serum + normal leucocytes + Staphylococcus albus. 50 cells = 

 254 cocci. 



The same serum, however, when added to immune leucocytes, which were 

 obtained from the patient from whom this identical organism was grown in 

 pure culture, and the Staphylococcus alhvs showed 106 cocci in 50 cells. 



While the immune serum obtained from this case, when added to the normal 

 leucocytes referred to above and the cocci, gave 388 cocci in 50 cells. 



{h) Immune serum of pulmonary tuberculosis acting in the presence of its 

 own leucocytes and cocci showed 174 cocci in 50 leucocytes, but when this 

 immune serum acted in the presence of normal leucocytes and the same 

 staphylococci, 50 cells contained 433 cocci. 



(c) One more experiment only will be referred to concerning this point. 



Normal serum + normal leucocytes + i^«ci//?is coli; 50 cells = 220 bacilli, 

 but when the same serum acted in presence of leucocytes from a case of acute 

 lobar pneumonia, 50 cells = 83 bacilli. 



In all these experiments on phagocytosis the serum was examined within a 

 few hours of its removal from the body, and was free from blood tinging, and 

 the various experiments were made at about the same period. 



Robert Muir, in the paper published in the ' Proceedings of the Eoyal 

 Society,' already referred to, furnished evidence to show that when a serum was 

 saturated with suitable red cells the normal opsonin was removed. In the 

 experiments which we have brought forward on human blood in the present 

 communication, we have similarly found that when a .serum is saturated with 



* *Eoj'. Soc. Proc.,' B, vol. 80, p. 165. 



