title: Modified par j I allergen from P judaica pollen and its rate of absorption in rats.
abstract: Polymerized allergens (allergoids) have been introduced in the immunotherapy of allergic disease in order to reduce the risk of side effects. However, their high molecular weight can be a limit, particularly when they are administered by a route involving passage through the mucosal barrier. We describe a simple procedure aimed at developing an original modified allergen with significantly less allergenic potential (intended as human IgE-binding capacity) but preserving the monomeric nature of the molecule. Par j I, the major allergen of Parietaria judaica pollen, was purified by a combination of monoclonal antibodies and affinity chromatography. Par j I allergen was then modified by reaction with potassium cyanate (KCNO), and compared with the native allergen to evaluate its allergenic potency (RAST-inhibition) and molecular weight (SDS-PAGE). Modified allergen showed significantly lower allergenic potency but kept its original molecular weight, making it particularly suitable for buccal (sublingual) administration. To study the adsorption profile, modified Par j I was radiolabeled and administered intravenously and sublingually to normal rats. The prospects for clinical application of the modified allergen are discussed.
authors.affiliation: Research Department, Laboratorio Farmaceutico Lofarma, Milano, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Mistrello
authors.forename: D
authors.initials: D
authors.lastname: Roncarolo
authors.forename: M
authors.initials: M
authors.lastname: Gentili
authors.forename: D
authors.initials: D
authors.lastname: Zanoni
authors.forename: P
authors.initials: P
authors.lastname: Falagiani
mesh_terms: D000042:Absorption; D000286:Administration, Sublingual; D000485:Allergens / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D000911:Antibodies, Monoclonal; D002846:Chromatography, Affinity; D006023:Glycoproteins / Q000302:isolation & purification / Q000378:metabolism*; D007073:Immunoglobulin E / Q000276:immunology; D007275:Injections, Intravenous; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010940:Plant Proteins; D011058:Pollen / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000485:Allergens; D000911:Antibodies, Monoclonal; D006023:Glycoproteins; C083860:Par j I protein, Parietaria judaica; D010940:Plant Proteins; D007073:Immunoglobulin E