[Alleviation of seasonal allergic symptoms with superfine beta-1,3-glucan: a randomized study].

Allergic response is induced by the Th2-type immune response. The intracellular thiol redox status of antigen-presenting cells (APCs) reportedly regulates the Th 1/Th 2 balance via distinctive cytokine production by APCs. The beta-1,3-glucan, lentinan, induces reductive macrophages (RMp) with elevated intracellular glutathione (icGSH), essential for the secretion of the Th 1-type cytokine, IL-12. This dou0 ble-blind, placebo-controlled randomized study shows that the ingestion of superfine dispersed beta-1,3-glucan alleviates ongoing symptoms of rhinoconjunctivitis. We postulate that the difference was due to inefficient lentinan uptake by the intestinal mucosa in the placebo group. Our interim results, obtained after only 2 months of treatment, show that the oral administration of beta-1,3-glucan in individuals with allergic tropism can reduce the spontaneous increase of both allergen-specific and total IgE titers. The clinical response to treatment was well correlated with both the decrease in IgE and the capacity of monocytes to bind to beta-1,3-glucan. Orally effective superfine dispersed beta-1,3-glucan may greatly contribute to the resolution of epidemic medical problems of seasonal cedar-pollen-induced allergy.