Reactive Power of the White Rat. 



43 



study of this question the white rat is certainly the most appro- 

 priate animal. 



22 (278) 



The hemolytic reactions of the blood in dogs with 

 transplantable lymphosarcoma. 



By RICHARD WEIL. 



[From the Huntington Fund for Cancer Research, of the General 

 Memorial Hospital, Loomis Laboratory, Cornell University 

 Medical College, Netv York City.~\ 



Dogs with lympho-sarcoma in every stage of growth were made 

 use of, including those in which growth was active and progressive, 

 those in which the tumor was quiescent, those in which the growth 

 was regressing, and those in which recovery with complete absorp- 

 tion of the tumor had taken place. Some of the dogs were in good 

 general condition, others were cachectic. Controls were also made 

 use of, including dogs in poor and in good condition. In all, the 

 material comprised 34 dogs, 18 with a tumor history, and 16 with- 

 out. These were all bled from the femoral artery or jugular vein. 

 In all of these dogs, blood was obtained for serum, and for a 1 

 per cent, suspension of corpuscles. The serum of each animal was 

 tested on the corpuscles of a number of other animals in order to 

 determine its hemolytic power. Up to the present time over 300 

 such tests have been made. The serum obtained from tumor dogs 

 is almost without exception possessed of hemolytic power. This 

 is least marked in the early and active stages of tumor growth, 

 more so in the broken down and softened tumors. It persists 

 even in the dogs which have recovered of their tumors. The cor- 

 puscles of the tumor dogs manifest a much greater resistance to 

 this hemolytic activity of the serum than do the corpuscles of 

 other dogs. The resistance is not absolute in the test tube, but 

 in dilutions which are just sufficient to demonstrate the hemolytic 

 activity of the serum from tumor animals on normal corpuscles, 

 the corpuscles from tumor animals remain intact. The serum of 

 animals without tumors has almost without exception failed to 

 show any hemolytic power and the corpuscles have not been 

 resistant to the serum derived from tumor dogs. 



