Effect of histamine, H1 and H2 agonists on E-rosette formation in normal and atopic subjects.

The effect of histamine on the capacity of human peripheral blood lymphocytes to form E rosettes was studied in normal and atopic subjects. Histamine had little effect on E-rosette formation (E-RF) in atopic subjects, but significantly inhibited E-RF in normal subjects in a dose-dependent fashion. To investigate this phenomenon further, specific histamine type 1 and 2 receptor agonists were used in the rosette assay. The H1 receptor agonist caused significant inhibition of E-RF in both normal subjects and atopics, whereas the H2 agonist produced significant inhibition of E-RF in normal but not atopic subjects. The results indicate a histamine type 2 receptor dysfunction in a subpopulation of atopic peripheral blood T lymphocytes.