CONCENTRATION OF ANTIBODIES 139 



Muir and Browning actually inhibited it in every series in the experi- 

 ment by at least two dilutions. In this case we have a cerebrospinal 

 fluid and an aqueous humor which contained agglutinins for rabbit 

 corpuscles but in these fluids the addition of rabbit serum completely 

 inhibited the action. We would not give the impression that this 

 occurred normally in our work, or even frequently, for in the nine 

 cases where complement was used with body fluids of immune dogs, 

 this phenomenon was noted in only this one experiment. It appeared 

 only once in the fluids of normal dogs, and in that case the action was 

 less marked. 



Conclusions. i . In the blood of dogs immunized with alien blood 

 hemolysins are faund in the serum, thoracic lymph, and neck lymph, 

 and usually in the pericardial fluid. They are not found in the cere- 

 brospinal fluid or aqueous humor. The comparative concentration 

 is the same as in the normal animal. 



2. -The addition of guinea-pig serum as complement in non- 

 hemolytic doses increases greatly the hemolytic power of the serum, 

 neck lymph, thoracic lymph, and pericardial fluid; therefore, in the 

 course of immunization the amboceptors are increased in the fluids, 

 while complement is not. Cerebrospinal fluid and aqueous humor 

 do not become hemolytic on the addition of complement; therefore, 

 they do not contain amboceptors. 



3. In the immunized dog the agglutinins are more concentrated 

 than in the same fluids of the normal animal. The usual order of 

 descending concentration is: serum, thoracic lymph, neck lymph, 

 pericardial fluid; but the order may be thoracic lymph, serum, neck 

 lymph, pericardial fluid. Cerebrospinal fluid and aqueous humor 

 may have agglutinins present but usually do not. If agglutinins 

 are present in these two fluids, the concentration is about equal and 

 lower than the pericardial fluid. 



4. Immunization of a dog to horse serum increases the hemolytic 

 power of the body fluids for horse corpuscles, but little if at all for 

 rabbit corpuscle. The hemagglutinins are increased to a slight 

 extent. 



5. Occasionally the addition of rabbit serum will inhibit the 

 agglutination of washed rabbit corpuscles by the fluids of a dog 

 immune to rabbit blood. 



