CIRCULATING SELECTINS, INTERCELLULAR-ADHESION MOLECULE-1, AND VASCULAR CELL-ADHESION MOLECULE-1 IN HYPERTHYROIDISM

Serum concentrations of soluble intercellular adhesion molecule-1 (sIC AM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble E- selectin (sE-selectin), soluble P-selectin, and soluble L-selectin (sL -selectin), tumor necrosis factor-alpha, and interleukin-6 were measur ed in patients with Graves' disease (GD) (n = 33), in patients with to xic nodular goiter (n = 34), and in a group of healthy controls (n = 3 6). The serum levels of sICAM-1, sVCAM-1, sE-selectin, and sL-selectin were markedly elevated in patients with GD and in patients with toxic nodular goiter before treatment with methimazole (P < 0.05 for all). After 8 weeks of therapy, serum concentrations of sVCAM-1 and sE-selec tin normalized. whereas serum levels of sL-selectin and sICAM-1 remain ed elevated. Hormone concentrations normalized after 2 weeks, clearly preceding falling levels of circulating adhesion molecules. Serum conc entrations of soluble P-selectin, TNF-alpha, and interleukin-6 did not differ among patients with GD and toxic nodular goiter and healthy su bjects. Serum levels of sVCAM-1 and sICAM-1 correlated with the serum concentrations of TSH receptor antibodies (n = 33; r = 0.921 and r = 0 .792, respectively) and thyroid peroxidase antibodies (n = 33; r = 0.6 82 and r = 0.761, respectively) but not thyroglobulin antibodies. Howe ver, no correlation between serum levels of sE-selectin, sL-selectin, and soluble P-selectin or cytokines and serum levels of thyroid peroxi dase antibodies, TSH receptor antibodies, or thyroglobulin antibodies, respectively. was found. In addition, no correlation between serum le vels of adhesion molecules or cytokines and thyroid hormones was seen. We conclude that both the action of thyroid hormones and the autoimmu ne process in GD may contribute to elevated levels of soluble adhesion molecules.