CONCENTRATION OF ANTIBODIES 



will show that the relative concentration of the agglutinins, in the 

 body fluids, remain the same during the process of immunization. 



That there is, however, a marked increase in the amboceptor 

 content of the body fluids, normally containing them, during the 

 process of immunization is shown by Table 3. 



TABLE 3 . 



LYTIC AND AGGLUTINATING POWER ON RABBIT CORPUSCLES OF THE BODY FLUIDS OF DOG IMMUNIZED 



WITH RABBIT BLOOD AS AFFECTED BY COMPLEMENT (0.2 c.c. FRESH GUINEA-PIG SERUM). 



(Intraperitoneal injections of rabbit blood as follows: December i, 5 c.c.; December 5, 7^ c.c.; 



December 10, 10 c.c.; December 15, 15 c.c.; December 21, 16 c.c.; January 16, 20 c.c. 



Fluids collected February 8.) 



This experiment shows very clearly that in the immunized animal 

 the serum, neck lymph, thoracic lymph, and pericardial fluid do not 

 contain complement in sufficient quantity to activate all of the ambo- 

 ceptor present in the fluid, because the addition of guinea-pig com- 

 plement,* in doses of itself not ly tic, is able to produce stronger 



* We experienced considerable difficulty in securing a complement which was effective and at the 

 same time did not of itself produce hemolysis. Rabbit serum, guinea-pig serum, and dog serum from 

 which the amboceptor had been separated in the cold were tried. The guinea-pig serum proved the only 

 effective one. 



