CYTOKINES AND ADHESION MOLECULES IN ALLERGIC RHINITIS

This review summarizes our current knowledge of nasal allergic inflamm ation based on studies of cytokines, chemokines, and adhesion molecule s in allergic rhinitis. The article also includes some aspects of vira l rhinitis. Due to artificial or natural allergen exposure, an increas e in the number of eosinophils and basophils, mast cells, IgE-positive cells, macrophages, monocyte-like cells, Langerhans cells, and activa ted T-cells can be observed within the mucosa and on the mucosal surfa ce. Mediators are known to be released in response to allergens, but d o not seem to be adequate to initiate the cell recruitment After antig en challenge, the release of proinflammatory and regulatory cytokines could be demonstrated and TH2-type cytokine mRNA upregulation in aller gic mucosa has been shown. Proinflammatory cytokines initiate an adhes ion cascade and activate T-cells that create an ''atopic'' cytokine en vironment within the tissue, which also may be linked to the long-term selective recruitment of eosinophils. However, the acute selective mi gration of eosinophils after allergen challenge is not fully understoo d nor is the role of chemokines in allergic and viral rhinitis. Allerg ic rhinitis clearly represents an inflammatory reaction.