title: Abnormal monocyte cytotoxicity and cyclic-AMP levels in systemic sclerosis.
abstract: Monocyte antibody-dependent cell-mediated cytotoxicity (ADCC) was compared to intrinsic cyclic-adenosine-monophosphate (cAMP) levels in 14 patients with systemic sclerosis. Depressed monocyte cytotoxicity was observed. Elevated cAMP levels (2-5 times) in resting monocytes were found in 5 patients; the rest had normal cAMP values. Monocyte ADCC was inversely correlated to cellular cAMP content (r = -0.6659, P less than 0.02). Scleroderma patients with high basal cAMP levels showed impaired responses to beta-adrenergic stimulation but not to prostaglandin E (PGE1) and histamine. Patients with normal basal cAMP levels showed no defect in beta-adrenergic responses. No close correlation between monocyte abnormality and clinical state was found.
mesh_terms: D000328:Adult; D000368:Aged; D000527:Alprostadil; D000920:Antibody-Dependent Cell Cytotoxicity; D000242:Cyclic AMP / Q000097:blood*; D005260:Female; D006632:Histamine / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D011458:Prostaglandins E / Q000494:pharmacology; D012595:Scleroderma, Systemic / Q000097:blood / Q000276:immunology*
chemical_list: D011458:Prostaglandins E; D006632:Histamine; D000242:Cyclic AMP; D000527:Alprostadil; D007545:Isoproterenol