94 The Lymphocyte and Lymphocytic Tissue 



it seems reasonable to conclude that the lymphocytes initiated the synthesis 

 of antibody and that during this period of synthesis metamorphosed to 

 transitional cells, then to preplasma cells, and finally to plasma cells (Table 



7-2). 



Table 7-2. Live Lymph Node Cells in Adult Recipients: Summary of Observations 



These experiments are not to be interpreted as denying the roles of other 

 cells of the mesenchyme in the synthesis of precipitating antibody but rather 

 to affirm the possibility that the lymphocyte can synthesize classic precipi- 

 tating antibody. Similar experiments using oil-induced peritoneal macro- 

 phages obtained from hyperimmunized donor rabbits and transferred to 

 x-radiated recipient rabbits have shown almost equal immunologic results. 48 

 Morphologically there was a decrease in macrophages paralleled by an in- 

 crease in first transitional cells, then preplasma cells, and finally in adult 

 plasma cells. The sites on the eighth day after the transfer of live peritoneal 

 macrophages were indistinguishable from the sites obtained on the eighth 

 day after the transfer of live lymphocytes. 



SUMMARY 



Donor rabbits were hyperimmunized to a bovine serum protein, albumin. 

 Known populations of viable lymph node cells obtained from these donors 

 at a time when the production of antibody was low were transferred to im- 

 munologically inert recipients. When these cells were stimulated by bovine 

 serum albumin in the recipients, specific antibody to bovine serum albumin 

 was subsequently detected in the recipients' sera. On the basis of correlated 

 immunologic and morphologic observations, the following conclusions seem 

 warranted: 



