Lupus erythematosus. Part I: epidemiology, genetics and immunology.

Lupus erythematosus (LE) is an important dermatologic autoimmune disease and in many aspects, including epidemiology, genetics, immunology, diagnostics and treatment, may be regarded as model for many other autoimmune diseases. Constant efforts in the past years have unraveled important new aspects of LE pathogenesis. Among these are the genetic associations with immunoregulatory signaling pathways such as TNF-, NF-κB-, IL23/IL17- and interferon pathway as well as new insights into the relevance of the innate immune system. Here Toll-like receptors and neutrophils play a central role. The knowledge about immune and autoimmune interactions in LE pathogenesis and the contributing cell types is steadily increasing and has led to new therapeutic approaches using antibodies directed against the B-cell activating factor BLyS. In the first part of this review article, the current knowledge about epidemiology, genetics and immunology is summarized. A second article will deal with diagnostics, clinical picture and different treatment modalities.