Effect of histamine on the spontaneous rosette formation.

Eight persons with clinically diagnosed hay fever were examined. The control group consisted of ten subjects without any signs of allergy. T lymphocyte subpopulation was evaluated by E rosette test. The effect of histamine was studied adding various concentrations of histamine (from 10(-9) to 10(-4) M) to the suspension of lymphocytes. A proportional drop in the percentage of the formed E rosettes could be seen at histamine concentrations ranging between 2 x 10(-9) and 2 x 10(-6) M. At 10(-6) up to 10(-4) M there was both an increase and further reduction in the percentage of the E rosette formation. A question arises whether there exists any correlation between the decreased number of T lymphocytes and elevated content of histamine in atopic persons?