Intranasal application of chitin microparticles down-regulates symptoms of allergic hypersensitivity to Dermatophagoides pteronyssinus and Aspergillus fumigatus in murine models of allergy.

BACKGROUND: Previous studies have demonstrated that chitin in the form of microparticles that can be phagocytosed is a potent macrophage stimulator and promotes a Th1 cytokine response and it has been shown that oral administration of chitin microparticles is effective in down-regulating serum IgE and lung eosinophilia in a mouse model of ragweed allergy. To date there have been no studies on the effectivness of directly applying chitin microparticles to the respiratory tract as a treatment for allergic symptoms.
OBJECTIVE: To test the effectivness of chitin microparticles when given intranasally as a treatment for the symptoms of respiratory allergy and allergic asthma and to compare its effectivness in two different mouse models of allergy, namely to Dermatophagoides pteronyssinus and Aspergilhus fumigatus.
RESULTS: The intranasal application of microgram doses of chitin microparticles is an effective treatment for reducing serum IgE and peripheral blood eosinophilia, airway hyper-responsiveness and lung inflammation in both allergy models results in elevation in Th1 cytokines IL-12, IFN-gamma and TNF-alpha and reduction in IL-4 production during allergen challenge.
CONCLUSION: Chitin microparticle suspensions have Th1 immunostimulatory properties and are effective when administered intranasally in mice. The stimulation of the nasal associated lymphoid tissue with chitin microparticles could offer a novel and natural approach to treating allergic disease in humans.