Antigenic Properties of Red Cell Globulin. 347 



and Schmidt. Rabbits were immunized by intraperitoneal injec- 

 tions of these respective antigens at definite intervals of time and 

 tests for the presence of hemolytic sensitizer and of agglutinin in 

 the serum of the injected animals were carried out as in the experi- 

 ment with the globulin from ox cells. The data follows: 



Rabbit No. 44 was given a total of 75 c.c. of a suspension of 

 C0 2 -globulin prepared from sheep cells. This corresponds to 

 35 c.c. of whole sheep blood and contained approximately 20 

 mgs. of nitrogen. The limit of the hemolytic titer was found 

 to be 0.4 c.c. of 1 : 6,000. The serum showed marked agglu- 

 tinative properties. 



Rabbit No. 45 received the same amount of sheep-cell globu- 

 lin as No. 44. The limit of the hemolytic titer was 0.2 c.c. of 

 1 : 6,000 and the sheep cells were markedly agglutinated by this 

 serum. 



Rabbit No. 40 was given a total dosage of 175 c.c. of C0 2 - 

 globulin prepared from pig cells, an amount which corresponds 

 to 80 c.c. of whole blood. Its content of nitrogen was 60 mgs. 

 The limit of the hemolytic titer was found to be 0.1 c.c. of 1 : 

 250 and this was also the limit of agglutination. 



Rabbit No. 42 received the same amount of pig-cell globulin 

 as No. 40. The limit of the hemolytic titer was found to be 

 0.1 c.c. of 1 : 250 and the highest dilution of serum which agglu- 

 tinated the pig cells was 0.3 c.c. of 1 : 1,250. 



Rabbit No. 36 was given a total dosage of 210 c.c. of human 

 red-cell globulin. This corresponds to 50 c.c. of whole blood 

 and contained 23 mgs. of nitrogen. The hemolytic titer of the 

 serum was found to be 0.2 c.c of 1 : 50 and a suspension of red 

 cells were agglutinated in a serum dilution of 1 : 250. 



Rabbit No. 37 received the same dosage of C0 2 -globulin from 

 human red cells as animal No. 36. The hemolytic titer of the 

 serum was found to be 0.1 c.c. of 1 : 10 and the highest dilu- 

 tion of serum which agglutinated red cells was 0.1 c.c. of 

 1 : 1,250. 



Rabbit No. 38 received the same dosage of human C0 2 - 

 globulin as the two previous animals. The hemolytic titer was 

 found to be 0.4 c.c. of 1 : 50 and the limit of agglutination was 

 0.1 c.c. of 1 : 1,250. It was not found possible to raise the 



