76 IMMUNO-CATALYSIS 



system was considered responsible for a reasonable portion of tbe 

 total amount of circulating antibodies. Histological studies showed 

 that tissues containing transitional cells were comparatively poor anti- 

 body-formers. The appearance of more mature cells was associated with 

 an increase in the antibody content of the culture fluid. The decrease 

 in the number of transitional cells was associated with an increase in 

 antibody content of the serum, and the latter distinctly coincided with 

 the number of immature cells showing growth. The transition of the 

 immature plasma cells into mature cells was observed to lead to a 

 decline in this capacity. 



According to Caspersson (1947), all protein synthesis needs the 

 presence of nucleic acids; quantitatively, the most important nucleic 

 acids in the chromosome are of desoxyribose* nature. The nucleus 

 itself is a cell organelle organized especially for being the main center 

 of the cell for the formation of proteins. In myeloma relatively large 

 amounts of plasma cells appear in the blood. They show the typical 

 picture of intense protein production (Thorell and Wising, 1944; 

 Thorell and Wilton, 1945). Bing, Fagraeus and Thorell (1945) re- 

 ported that a great amount of ribose nucleotides is found in the 

 cytoplasm of the immature plasma cells. The nucleotide content to- 

 gether with the well developed nucleolar apparatus was considered to 

 indicate an intensive production of protein in the cell. They consider 

 the appearance of plasma cells as a sign that a conversion and an 



*In a recent study Ehrich et al. (1949) observed that there is a parallehsm between 

 the increase in desoxyribosenucleic acid and the increase in the weight of lymph 

 nodes involving active cell multiplication. The peak of pentosenucleic acid increase 

 was found to occur between the 4th and 6th day after vaccine injection when anti- 

 body formation was at its maximum. A histological study showed that on the 5th and 

 6th day mature plasma cells were the prevailing cells. Most of the pentosenucleic acid 

 was contained in the plasma cells. A comparison of the rates of the proliferation of 

 lymphocytes and plasma cells with the pentosenucleic acid and antibody formation 

 showed that the plasma cells and not the lymphocytes are responsible for antibody 

 formation. 



A somewhat different point of view regarding the seat of the antibody synthesis 

 is maintained by Harris and Harris (1949). After injecting antigenic and non- 

 antigenic materials into the foot-pads of rabbits, the draining (pophteal) lymph 

 nodes were daily studied histologically, chemically, and serologically. Non-antigenic 

 materials showed no change. In response to antigenic materials the concentration 

 of pentosenucleic acid rose to more than twice its normal value by the 2nd to 5 th 

 day followed by a decline. The peak of this change occurred at or slightly before 

 the appearance of the maximal concentration of antibodies in the same node. The seat 

 of these changes are believed to be the large, young lymphocytes, a view which 

 differs from that which considers the plasma cells as the seats of antibody synthesis. 



