Effect of Oromucosal Administration of IFN- α on Allergic Sensitization and the Hypersensitive Inflammatory Response in Animals Sensitized to Ragweed Pollen

Abstract

Oromucosal (o.m.) administration of interferon-α (IFN-α) during either allergic sensitization (days 0-6) or the hypersensitive response (days 11 and 12) or both periods caused a dose-dependant reduction in allergen-specific IgE production and allergen-induced eosinophil recruitment in mice sensitized to ragweed pollen, a common allergen in humans. Treatment during the hypersensitive response period alone appeared to be most effective. Oromucosal treatment was as effective as intraperitoneal (i.p.) treatment, with maximum inhibition of both allergen-specific IgE production and allergen-induced eosinophil recruitment observed at a dose of a 1000 IU IFN-α. Treatment of animals with up to 10⁵ IU murine IFN-α/β (MuIFN-α/β) by either the om. or i.p. route did not inhibit significantly allergen-specific IgG production, which may even have been increased at certain doses of IFN. Treatment of animals with up to 10⁵ IU MuIFN-α/β by either the o.m. or i.p. route did not affect significantly total serum IgE or IgG levels. Oromucosal administration of IFN-α reduced allergen-specific IgE production and allergen-induced eosinophil recruitment in the absence of detectable toxicity, the induction of H₂ antigen expression, and 2′,5′-oligoadenylate synthetase activity associated with parenteral administration of IFN-α and thus may find application for the treatment of asthma and associated viral infections.