An in vitro study of depressed cell-mediated immunity and of T and B lymphocytes in atopic dermatitis.

Lymphocyte transformation tests, E binding(T) rosette assay and immunofluorescent preparations of B cells were studied in patients with atopic dermatitis, and also in healthy controls. Most of the patients were found to have high levels of IgE in serum. The patients were studied both during severe bouts of dermatitis and also when the dermatitis was almost healed. Lymphocyte transformation tests showed that patients were hyporeactive to PPD and herpes simplex antigen in vitro, both during periods of severe dermatitis and also when the dermatitis was in remission. The response to PHA in the patients was normal in vitro. No factors which could reduce cell-mediated immunity in vitro were found in patients' sera. A decreased number of T lymphocytes and a slight increase in the number of immunoglobulin-bearing lymphocytes (B cells) were demonstrated in the patients, both during remission and during recurrence of severe dermatitis. In 3 of 8 patients, increased numbers of IgE-bearing lymphocytes were found to be present when the patients had severe dermatitis. A possible correlation between high serum levels of IgE and depressed cell-mediated immunity in patients with atopic dermatitis is discussed.