Effects of long‐term procainamide therapy on immunoglobulin synthesis

Abstract

Procainamide is a potent inducer of autoantibodies. In order to evaluate the immunologic effects of this drug in vivo, 23 cardiac disease patients who had received procainamide for at least 6 months and an equal number of matched cardiac disease control subjects were studied, and percentage of circulating T cell subsets, concanavalin A-induced suppressor cell activity, and pokeweed mitogen-stimulated generation of immunoglobulin-secreting cells was quantitated. There was no significant difference between patient and control groups in the percentage of T cell subsets defined by OKT4 and OKT8 monoclonal antibodies or in concanavalin A-induced suppressor cell activity. The numbers of pokeweed mitogen-induced immunoglobulinsecreting cells were markedly decreased in the patient group, as measured by the protein A-augmented reverse hemolytic plaque assay (3,000 +-644, mean f SEM in patients versus 10,826 f 1,529, mean f SEM in control subjects, P < 0.005). Removal of the adherent cell fraction did not improve the hyporesponsiveness. When B and T cell fractions of 6 patients were mixed with

Drug-Induced Immune Hemolytic Anemia

“…130 4. 136,137 They found that patients on long-term procainamide therapy had normal numbers and ratios of helper and suppressor T cells and normal mitogeninduced suppressor cell activity. [131][132][133][134][135][136] The reported effects on cellular immune function conflict with one another, and the described effects were small, requiring relatively high concentrations of procainamide.…”

Mechanism of drug-induced lupus

“…Shamess et al also found normal suppressor T-cell activity in patients taking procainamide who had ANA (52). Yu and Ziff found that cells from patients treated with procainamide had a normal ratio of helper to suppressor cells but diminished B-cell response, even in the presence of T-cells from normal subjects (53). Drug was not present during these incubations; therefore, the observations represent an irreversible effect of the drug or its metabolites on the cells.…”

Defective Helper T Cell Function in IgM Rheumatoid Factor Synthesis in Patients with Ankylosing Spondylitis

“…Con A-induced suppressor cell activity Non-specific suppressor cell activity was evaluated from 6 AS patients by a two-stage method as described by Yu et al (13). Briefly, 5x106/ml mononuclear cells were stimulated with 30 pg/ml of concanavalin A (ConA, Pharmacia Fine Chemicals, Uppsala, Sweden) and cultured at 37"C, 5 % C02 in Petri dishes, with continuous shaking for 48 h. As a control, ConA was added to the non-activated control cells just before harvest.…”