172 



Scientific Proceedings (76). 



evidently an opsonin or bacterio-tropin so altering the pneumo- 

 cocci as to cause their adhesion to the capillary walls. 



This opsonin is relatively inactive for the extrahepatic capil- 

 laries. The hind-quarters, lungs, kidney and intestines of normal 

 rabbits can be repeatedly perfused with Ringer's solution con- 

 taining as much as I per cent, immune serum, with only a slight 

 retention of the pneumococci by these organs, while 0.001 per 

 cent, immune serum will cause their quantitative retention by the 

 liver. (Spleen and bone-marrow not yet tested.) 



Defibrinated normal rabbit blood used as the perfusion fluid 

 will cause a slight deposit of the pneumococci in all organs. 



95 ("59) 



Specific receptors of fixed tissues. 



By W. H. Manwaring and Yoshio Kusama. 



[From the Department of Bacteriology and Immunity, Leland Stan- 

 ford, Jr., University.) 



If Ringer's solution containing 1 per cent, goat serum is re- 

 peatedly perfused through the blood-free liver of a normal, ana- 

 phylactic or immune rabbit, no diminution in the amount of goat 

 serum in the perfusion fluid is produced, that can be detected by 

 titration with a specific precipitating serum. 



If defibrinated normal, anaphylactic or immune rabbit blood 

 is added to the perfusion fluid, diminutions in the amount of goat 

 serum are observed after repeated liver passage; but in all cases 

 these diminutions are identical with diminutions observed in 

 control samples of the fluid kept at incubator temperature and 

 not passed through the liver. 



The perfusion experiments therefore furnish no evidence of the 

 existence of a specific receptor apparatus (Ehrlich) for goat pro- 

 teins, in normal, anaphylactic, or immune rabbit livers. 



