T cell subpopulations and their functions in vitro. A study in patients with alopecia areata and alopecia universalis.

T lymphocyte subpopulations and their in vitro activities were determined in patients with alopecia areata (AA) and alopecia universalis (AU). The frequencies of T cells with receptors for IgG and T cells with receptors for IgM were determined in 16 cases. The IgG and IgM production of B lymphocytes cocultured with autologous and allogeneic T lymphocytes in the presence of PWM was determined in 12 and 9 cases, respectively, and the antibody-dependent cell-mediated cytotoxicity (ADCC) of unfractionated lymphocytes was examined in 6 cases. Patients with AA and AU had a higher proportion of Tg cells and more pronounced ADCC of unfractionated peripheral lymphocytes than normal persons. Furthermore, PWM-induced Ig production of B lymphocytes in the presence of autologous T lymphocytes seemed to be lower than that of controls.