Suppressor-cell functions in bullous pemphigoid.

T Cells from 14 patients in the active stage of bullous pemphigoid and 10 patients in the inactive stage of the disease were studied with Leu-1, Leu-2, and Leu-3 monoclonal antibodies. The proportions of total T cells and T cells expressing either helper or suppressor phenotype in the peripheral blood of patients were not significantly different to those observed in normal subjects. In 15 patients with active disease, immunoregulatory mechanisms were functionally studied using an assay measuring the amount of total IgG synthesized in vitro. Peripheral-blood leukocytes were separated into T- and B-cell fractions, and cultured in various combinations. In ten experiments, prior to culturing with B cells, the T cells were irradiated to remove their suppressor function. No statistically significant differences were observed in the amount of total IgG synthesized by B cells obtained from patients and normal subjects when they were cultured with untreated T cells or irradiated T cells obtained from patients or normal controls. These results indicate that, in patients with bullous pemphigoid, there is no loss of suppressor-cell function or increased helper-cell function as assessed by measuring the total IgG synthesized. Therefore, the immunoregulatory defect, if present, is a highly specific one and can only be studied using antigen-specific assays.