title: Misoprostol Inhibits the Cutaneous Late-Phase Allergic Response to Antigens. Results of a Double-Blind Placebo-Controlled Randomized Study and an Investigation into the Mechanism of Action.
abstract: We investigated the effect of misoprostol on allergen-induced cutaneous immediate- and late-phase allergic reactions in a double-blind placebo-controlled randomized study. Sixteen dust-mite-allergic patients received misoprostol (200 &mgr;g) or placebo and then had skin testing on two different days. The immediate- and late-phase skin response was monitored for 6 h. Skin biopsy was obtained from five selected donors at 5 h. In vitro studies included the effect of misoprostol on eosinophil chemotaxis, eosinophil survival, basophil histamine release, and cytokine production by lymphocytes. All subjects developed an immediate wheal reaction and a late-phase induration in response to dust-mite allergens after taking placebo. Misoprosol selectively inhibited the late-phase but not the immediate-phase response (p < 0.05). Histologic studies revealed a trend toward a reduced number of inflammatory cells in the skin dermis after misoprostol treatment. We also investigated the mechanism of action of misoprostol in vitro. Misoprostol significantly (p < 0.05) inhibited eosinophil chemotaxis and the production of granulocyte/macrophage colony-stimulating factor by lymphocytes at concentrations greater-than-or-equal10(minus sign8) M. However, at significantly lower concentrations (greater-than-or-equal10(minus sign12)M), misoprostol blocked cytokine-stimulated eosinophil survival. Thus, misoprostol has potent antiallergic effects and blocks the cutaneous late-phase allergic inflammation.
authors.affiliation: Division of Allergy & Immunology, Departments of Internal Medicine Pathology The University of Texas Medical Branch, Galveston, TX, USA.
authors.forename: Rafeul
authors.initials: R
authors.lastname: Alam
authors.forename: Alan
authors.initials: A
authors.lastname: DeJarnatt
authors.forename: Susan
authors.initials: S
authors.lastname: Stafford
authors.forename: Patricia A.
authors.initials: PA
authors.lastname: Forsythe
authors.forename: Dhruv
authors.initials: D
authors.lastname: Kumar
authors.forename: J. Andrew
authors.initials: JA
authors.lastname: Grant