Defective low-density cells of dendritic morphology from the blood of patients with common variable hypogammaglobulinaemia: low immunoglobulin production on stimulation of normal B cells.

Low-density cells (LDC) of dendritic morphology from the blood of patients with common variable (late-onset) hypogammaglobulinaemia (CVH) did not induce allogeneic immunoglobulin production by normal B cells unlike LDC from normal blood. When LDC from patients were treated with pokeweed mitogen (PWM), a lower allogeneic secretion of IgM and IgG was induced in normal B cells than that induced by allogeneic normal LDC treated with PWM. B cells from hypogammaglobulinaemic patients were non-responsive to both normal and patient LDC treated with PWM under all conditions tested.