Glucocorticosteroid enhancement of immunoglobulin synthesis by pokeweed mitogen-stimulated human lymphocytes. III. Common variable immunodeficiency.

We studied the effect of glucocorticosteroids (GCS) on IgG synthesis by peripheral blood mononuclear cells from 19 patients with common variable immunodeficiency (CVID). Purified T and B lymphocyte subpopulations from patients and normal subjects were recombined at various T : B ratios and cultured for 8 days unstimulated, stimulated with pokeweed mitogen (PWM) and in the presence of prednisolone. IgG synthesis was measured in the culture supernatants by radioimmunoassay. Enhancement of PWM-stimulated IgG synthesis by prednisolone at high T : B ratios was found in nine patients, four of whom produced negligible amounts of IgG with PWM alone. In four patients, enhancement by prednisolone of IgG synthesis by purified B lymphocytes was noted. In three out of eight patients whose IgG synthesis was increased by normal allogeneic T lymphocytes with PWM and prednisolone, negligible amounts of IgG were produced by similarly treated autologous combinations. T lymphocytes from CVID patients provided less help compared with normal T lymphocytes for IgG synthesis by normal B lymphocytes at high T : B ratios even in the presence of prednisolone. GCS in vitro enhance IgG synthesis by lymphocytes from some but not all patients with CVID by a mechanism which appears independent of GCS action on regulatory T lymphocytes.