0000000000765572
AUTHOR
T. Hultsch
Direct evidence that FK506 inhibition of FcεRI-mediated exocytosis from RBL mast cells involves calcineurin
eRI-mediated exocytosis of preformed mediators from mast cells and basophils (e.g. histamine, serotonin, beta-hexosaminidase) is sensitive to the immunosuppressants cyclosporin A and FK506 (IC 50 200 and 4 n M , respectively) but not rapamycin. The mechanism of inhibition does not appear to involve tyrosine phosphorylation, hydrolysis of inositol phosphates or calcium flux. Here we report experiments using a molecular approach to assess the role of calcineurin, a serine/threonine phosphatase thought to be the primary pharmacological target of these drugs. Calcineurin’s activity requires association of its catalytic (A) subunit with an intrinsic regulatory (B) subunit. We hypothesized that c…
Eosinophils, pruritus and psoriasis: effects of treatment with etretinate or cyclosporin-A
Abstract Background The antipsoriatic drugs cyclosporin A (CyA) and etretinate have been found to influence proinflammatory eosinophilic leukocytes and pruritus. Aim We compared the number of blood eosinophils, concentration of serum eosinophil cationic protein (ECP), and pruritus in patients with psoriasis treated with either CyA or etretinate. Study design Patients with psoriasis vulgaris were randomly assigned to treatment for 10 weeks with either CyA ( n =21) or etretinate ( n =10). The psoriasis area-and-severity index (PASI-score) and pruritus (according to a 0–3 scale) served as clinical parameters, the blood esosinophil counts (Coulter Counter) and the serum ECP (RIA, Pharmacia) as …