ANTIBODY PRODUCERS 



potentialities of lymphocytes giving rise to cells of other 

 functional type. Since the work of McMaster and Hudack 

 (1935) there has been no doubt that antibody was produced 

 in lymph nodes and spleen, but the general view has been 

 that the actual producers are plasma cells. It is extremely 

 difficult to obtain a gross preparation of lymphocytes that 

 can be ' certified ' free of plasma cells and there must always 

 be some doubt as to the composition of the cells used in 

 various forms of tissue survival experiments in vitro. Perhaps 

 the most convincing evidence is that of Wesslen (1952) who 

 used thoracic duct lymph from rabbits immunized some 

 time previously with Salmonella paratyphi B, This contained 

 extremely few cells other than small lymphocytes. Extraction 

 of the cells with distilled water provided no detectable anti- 

 body, but if they were incubated overnight in Tyrode solu- 

 tion small amounts of antibody were liberated into the 

 medium. This suggests perhaps no more than a potentiality 

 that when conditions are appropriate lymphocytes in an 

 immune animal can liberate antibody. 



Many experiments have been described in which cellular 

 transfer of immunological reactivity has been accomplished. 

 Lymph-node cells, or those from subacute peritoneal 

 exudates, are those commonly used, and in all such prepara- 

 tions there are numerous lymphocytes. In fact, it is probably 

 true to say that in recent years most authors have taken it for 

 granted that lymphocytes were the cells concerned in the 

 process. Dixon, Weigle and Roberts (1957) have recently 

 clarified the position somewhat by showing transfer of anti- 

 body-producing capacity, either by lymph-node cells with 

 80 to 90 % lymphocytes or by peritoneal exudates 80 to 90 % 

 monocytic in character. In each case the dose used was close 

 to the marginal, so that it could be said that in neither case 

 could the minority type have been wholly responsible for the 

 effect. 



This seems to point strongly to a unitarian interpretation 

 which has, in fact, been strongly defended for some years 



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