THE DETECTION OF IGE-SECRETING CELLS IN THE PERIPHERAL-BLOOD OF PATIENTS WITH ATOPIC-DERMATITIS

We report, for the first time, the identification of IgE-secreting cells in human peripheral blood with an ELISA plaque assay that detects the fingerprint of individual IgE-secreting cells. No IgE-secreting cells could be detected in the blood of normal individuals (IgE, < 100 IU/ml) or atopic patients (IgE, < 1000 IU/ml), but in patients with atopic dermatitis (AD) whose IgE was > 2000 IU/ml, there was an average of 49 +/- 9 IgE-secreting cells per 10(6) peripheral blood mononuclear cells (PBMNCs). The rate of IgE production per cell per day from the PMBNCs of patients with AD varied from 0.051 to 0.628 IU/ml, and the number of IgE-secreting cells was positively correlated with the serum-IgE levels of these subjects (r = 0.74; p < 0.001) and the amount of IgE detected in the culture supernatant (r = 0.085; p < 0.02). Secretion of IgE by these cells could be completely inhibited (96.2% +/- 3%) by the addition of 75-mu-g of cyclohexamide to the cultures. Preformed intracellular IgE comprised 10% of the IgE detected in the supernatants of 7-day cultures. PBMNCs from patients with AD depleted of monocytes by adherence and T cells by E rosetting, all contained some detectable IgE-secreting cells, whereas isolated T cells and monocytes did not, supporting the view that cells secreting IgE that were detected were indeed B cells.