PROINFLAMMATORY CYTOKINES IN ALLERGIC RHINITIS

Allergic diseases such as allergen-induced rhinitis represent an infla mmatory reaction that is characterized by the chemotaxis and activatio n of various cell populations. A high degree of cell-to-cell communica tion is needed to orchestrate this inflammatory immune responses. A va riety of cytokines an adhesion receptors seen to play an important rol e in the allergic late phase reaction. Here we demonstrate that proinf lammatory cytokines such as interleukin(IL)-1, IL-8 and TNF-alpha (tum or necrosis factor-alpha) can be detected in nasal secretions and muco sa by enzyme-linked immunosorbent assay and immunohistochemistry. The increased expression of adhesion receptors in mucosa specimens of pati ents with seasonal allergic rhinitis points to their role in regulatin g the cellular migration and probably represents a key event in allerg ic inflammation. We established an in vitro model using freshly taken nasal mucosa to study the induction of adhesion receptors by proinflam matory cytokines. E-selectin, an endothelial receptor, was strongly up regulated by IL-1 beta, TNF-alpha and allergen. The induction due to a llergen exposure of the mucosa was markedly inhibited by soluble cytok ine receptors (sIL-1R, TNF-BP) or by a receptor antagonist (IL-1ra) an d prednisolone, These findings indicate that proinflammatory cytokines may be key factors for the upregulation of adhesion processes in huma n nasal mucosa and the activation of various cell populations involved in the allergic inflammation. They therefore represent a main target for new therapeutic strategies.