68 IMMUNO-CATALYSIS 



Australia. Ehrich and Harris (1942) injected typhoid bacilli or 

 washed sheep erythrocytes subcutaneously in the hind legs of rabbits 

 and determined the antibody titers in the afferent lymph, in the sub- 

 stance of the lymph node, in the efferent lymph, and in the serum. 

 In a later study, Harris et al. (1945) separated the lymphocytes 

 from the lymph plasma, prepared a cell extract and compared its con- 

 tent of antibody with that of the surrounding fluid. Ehrich and Harris 

 (1945), after a review of the observations pertaining to the reticulo- 

 endothelial theory, summarized their results in the following manner. 

 "When antigens were injected into the pad of the hind foot of the 

 rabbit, antibodies first appeared two to four days after the injection in 

 the lymph draining from the popliteal lymph node (the only node 

 regional to the site of injection). They reached their highest titer 

 after six days. In all experiments it was found that the antibody 

 titer was higher in the efferent lymph; in some cases the concentration 

 was 100 times that found in the lymph of afferent vessel. The produc- 

 tion of antibody was preceded and accompanied by a rise in the output 

 of lymphocytes in the efferent lymph which ranged from 15,000 to 

 20,000 per c.mm. to 60,000 to 80,000 per c.mm. or more. At the same 

 time hyperplasia of the lymphatic tissue within the node occurred 

 resulting in some experiments in a weight increase of the node from 

 0.2 g. to 1.0 g. or more. During antibody formation in the popliteal 

 lymph node of rabbits, the lymphocytes in the efferent lymph vessels 

 contain antibodies in a much higher concentration than the surround- 

 ing lymph. The ratio of titers amounted to from eight to 16 in many 

 instances." Commenting on the lack of phagocytic activity of lympho- 

 cytes in relation to the antibody formation, and interpreting differently 

 the results of Sabin (see page 72), they reason that the lymphocyte 

 goes into action only after the raw material, i.e., bacteria or other 

 formed antigens, have been properly prepared by the action of micro- 

 or macrophages. In conclusion, they are of the opinion that the poly- 

 morphonuclear leucocytes and the macrophage as well as the lympho- 

 cyte may be instrumental in the antibody production, or through the 

 cooperation of all these elements the immune bodies may be produced. 

 In a series of studies, Dougherty, Chase and White (1944), and 

 White & Dougherty (1946), immunized mice against washed sheep 

 erythrocytes. They found that the antibody titers in the extracts from 

 three times washed lymphoid cells from immunized mice were ap- 



