Epigenetics of autoimmune diseases

Abstract

This chapter provides several examples of epigenetic deregulation in autoimmune diseases, a heterogeneous group of human conditions characterized by a deregulated immune response against the body own organs and tissues. Early studies based on the candidate gene approach have been flanked by genome-wide screenings in the last few years, revealing global changes in DNA methylation or histone tail modifications, as well as deregulated methylation and/or expression of hundreds of genes and microRNAs in cells from patients affected by those disorders. This chapter will focus on epigenetic deregulations observed in systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, psoriasis, multiple sclerosis, systemic sclerosis, and autoimmune thyroid diseases, even though epigenetic modifications are increasingly being observed in many other autoimmune diseases. By contrast, only a few environmental factors have been shown or suspected to induce the observed epigenetic changes. Epigenetic drugs and RNA silencing experiments have often reversed autoimmune disease-like phenotypes in rodents or cell cultures, leading researchers to debate on their potential use in the treatment of these human conditions.