Differences in effect of isoproterenol stimulation on levels of cyclic AMP in human B and T lymphocytes.
The level of cyclic AMP (cAMP) in human lymphocytes in the presence or absence of isoproterenol stimulation was studied in various lymphocyte subpopulations containing different proportions of B and T lymphocytes. Lymphocytes from thymus and peripheral blood (which contain a majority of T cells) were more sensitive to isoproterenol action than lymphocytes from tonsils or adenoids (where B cells are predominant). Using purified B or T lymphocytes from peripheral blood, tonsils or adenoids, we observed an absence of B lymphocyte response to isoproterenol, whereas T lymphocytes, which had a lower basal c-AMP level than B cells, exhibited in all experiments a significant increase in cAMP content after isoproterenol stimulation. The intensity of the response varied in the different T lymphocyte subpopulations.