[Adenosine triphosphatase and 5'-nucleotidase activity of antigen-stimulated lymphocytes]

Albion mice were immunized with a suspension of sheep erythrocytes. The animals were killed on the fifth and eighth day, and lymphocytes were taken from their spleen tissue. Studied was the activity of the adenosinetriphosphatase and 5'-nucleotidase in the lymphocytes during the immunogenesis in terms of their link with the cellblast transformation. The enzyme activity was determined by the method of Emmelot, Bos, and the extent of the blast transformation was expressed by the so-called blastogenic index (BI). It was found that: 1. During immunogenesis 32% of the lymphocytes in the mouse spleen are transformed into blast cells. 2. The activity of 5'-nucleotidase drops, and that of adenosinetriphosphatase rises. 3. Parallelism exists between the extent of the lymphocyte blast transformation and the level of adenosinetriphosphatase. 4. The drop in the activity of 5'-nucleotidase is considered to be the aftermath of the drop in the intracellular adenosinetriphosphatase content.