CONCENTRATION OF ANTIBODIES 



TABLE 9. 

 THE COMPARATIVE AGGLUTINATING POWER ON THE TYPHOID BACILLUS OF THE BODY FLUIDS OF A 



DOG IMMUNIZED WITH RABBIT BLOOD. 



(Intraperitoneal injections as follows: October 10, ioc.c.; October 19, 8 c.c.; October 24, 8 c.c.; 

 October 29, 9 c.c.; November 3, 10 c.c.; November 9, 10 c.c.; November 14, 10 c.c.; fluids drawn 

 November 24.) 



A comparison of this table with Table 7 shows that the agglutinins 

 for the typhoid bacillus were little if any higher than those of the 

 normal animal, altho this was one of our most highly immunized 

 animals and agglutinated rabbit corpuscles strongly in a dilution of 

 i : 1,536 in the serum and in a dilution of 1 1384 in the neck and the 

 thoracic lymph. The relative concentration in the body fluids is 

 strictly comparable to those in the normal animal cited. We tested 

 also the blood serum of two other dogs immune to rabbit blood with 

 exactly similar results. 



C. Passive immunity. Evidence that antibodies of various kinds 

 are able to pass through membranes is not lacking in the literature. 

 Ehrlich 10 found that the young from a mouse immune to abrin, ricin, 

 or robin possess an immunity to these poisons which persists for two 

 months. Ascoli 1 found that the antibodies of the new born child 

 come from the maternal circulation and are not formed in the fetus 

 itself. This being true, the antibodies of the fetus have penetrated 

 the walls of at least a double membrane. Merkle 29 found that the 

 same was true for rabbits, since the young born of a mother immune 

 to human blood contain antibodies for human blood, altho they suckle 

 a normal mother from the very first. Liidke 23 confirmed the work 

 of Merkle. Ricketts 39 has shown that the young born to a guinea- 

 pig mother immune to Rocky Mountain spotted fever possess an 

 immunity to that disease, altho they suckled a normal mother. 

 DeBlasi 8 has shown that if a cat is immunized post par turn to B. 

 dysenteriae the young develop an immunity from the milk. This is 

 even a more striking example than the others of the ability of anti- 

 bodies to penetrate membranes, for in this case the antibodies after 

 reaching the alimentary canal of the young animal must penetrate 



