CYTOKINE-INDUCED INFLAMMATION IN THE CENTRAL-NERVOUS-SYSTEM REVISITED

Cytokines play an essential role as mediators of the immune response. They usually function as part of a network of interactive signals that either activate, enhance, or inhibit the ensuing reaction. An importa nt contribution of this cytokine cascade is the induction of an inflam matory response that recruits and activates subsets of leukocytes that function as effector cells in the response to the sensitizing antigen . Proinflammatory cytokines activate endothelial cells (EC) to express adhesion molecules and induce the release of members of the chemokine family, thus focusing and directing the inflammatory response to site s of antigen recognition. However, the vasculature of the central nerv ous system (CNS) is highly specialized and restricts the access of com ponents of the immune system to the CNS compartment. In this review, w e address the question as to whether endothelial cells in the CNS resp ond differently to specific cytokines known to induce either a proinfl ammatory effect or a regulatory effect in systemic vascular beds.