Alveolar macrophage - T cell interactions during Th1-type sarcoid inflammation

Sarcoidosis is an immunomediated, multisystem disorder of unknown cause(s) characterized by a heightened Th1 immune response that leads to an uncontro lled granuloma formation at sites of disease activity. The past few years h ave seen outstanding advances in the understanding of immunological and mol ecular events involved in the pathogenesis of this disease. The idea is tha t several cytokines and chemokines, which are secreted at sites of disease activity, participate in granuloma formation. This paper describes recent d ata that have clarified some of the events that govern the development of t he hypersensitivity reaction during sarcoidosis. In particular, we will rev iew recent evidence indicating that a complex relationship exists between t he macrophage/lymphocyte cellular axis and the tissue networks of cytokines . (C) 2001 Wiley-Liss, Inc.