Toll-like receptor (TLR) 4 Asp299Gly and Thr399Ile polymorphisms are associated with a chronic progressive course of pulmonary sarcoidosis

Background: The aetiology of sarcoidosis, an inflammatory granulomatous multisystem disorder, is unclear. It is supposed to be the product of an unknown exogenous antigenic stimulus and an endogenous genetic susceptibility. Toll-like receptors (TLR) are signal molecules essential for the cellular response to bacterial cell wall components. Lipopolysaccharide (LPS), for example, binds to TLR 4. Two different polymorphisms for the TLR4 gene (Asp299Gly and Thr399Ile) have recently been described. This leads to a change in extracellular matrix function of TLR4 and to impaired LPS signal transduction. Methods: We gen…