A. P. Weetman

The enhancement of immunoglobulin synthesis by human lymphocytes with lithium

Using a protein A plaque assay to detect immunoglobulin synthesis we have shown that culture of pokeweed mitogen (PWM)-stimulated lymphocytes in the presence of lithium significantly increased IgG production at concentrations of 10−3 to 10−2 mM. Enhanced IgG and IgM synthesis was found in cultures with lithium alone at concentrations of 1–10 mM, levels within the therapeutic range. Significantly higher numbers of spontaneous IgM plaque-forming cells were found in the peripheral blood of patients receiving lithium carbonate therapy than in normal controls suggesting that these findings may have clinical relevance.

Enzyme-linked immunoassay of monoclonal and serum microsomal autoantibodies

An automated enzyme-linked immunoassay for the detection of antibodies to human thyroid microsomes has been assessed. This assay correlated closely with the established commercial passive haemagglutination method. Variations in the purity of crude microsome preparations and the degree of thyroglobulin contamination make careful comparison of different preparations essential for meaningful interpretation of results, and attempts to circumvent these problems by further purification of microsome preparations using gel filtration are discussed. The application of this method for routine screening of serum samples is demonstrated using populations of normal subjects and patients with rheumatoid arthritis and anti-glomerular basement membrane disease. This assay has also permitted the establishment of murine hybrid myelomas secreting monoclonal antibodies to human thyroid microsomes.

Sex hormones enhance immunoglobulin synthesis by human peripheral blood lymphocytes

Using a protein A haemolytic plaque assay to detect immunoglobulin synthesis by human peripheral blood lymphocytes cultured with pokeweed mitogen, we have shown a significant increase in IgG plaque-forming cells in the presence of physiological concentrations of testosterone and oestradiol. Higher concentrations of these steroids inhibit plaque-forming cells. There was no difference in the response to testosterone and oestradiol of lymphocytes derived from male subjects or menstruating or post-menopausal females.