Prevalence and significance of autoantibodies in acute and chronic liver diseases and hepatocellular carcinoma

Abstract

Generally speaking, autoantibodies are B cell generated and also serologically detectable evidence of a loss of tolerance against cellular self structures, which can originate from different subcellular compartments (1-3). Autoantibodies have been described that target membrane-bound proteins of the cell and nuclear membranes and that reside in the cytoplasm or in other organelles such as the endoplasmic reticulum (Table 1) or mitochondria (Table 2). The proteins that are targeted include structural components such as actin or myosin and functional proteins such as metabolizing enzymes including cytochrome P450 (CYP), UDP-glucuronosyltransferases (UGTs), or pyruvate dehydrogenase (PDH). The identification of a specific epitope has stimulated research in an effort to characterize autoantibody-autoantigen reactivity as a tool to gain insight into the mechanisms of and the players involved in autoimmunity. However, the demonstration of a specific autoepitope reactivity does not preclude the possibility of crossreactivity of an exogenous antigen recognized by the immune system that displays homology with endogenous proteins of the body. © 2007 Humana Press Inc.