Autoantibodies and Autoimmunity
Published Online: 15 SEP 2006
Copyright © 2006 Wiley-VCH Verlag GmbH & Co. KGaA
Encyclopedia of Molecular Cell Biology and Molecular Medicine
How to Cite
Pollard, K. M. 2006. Autoantibodies and Autoimmunity. Encyclopedia of Molecular Cell Biology and Molecular Medicine.
- Published Online: 15 SEP 2006
Autoimmunity is an immunological reaction against constituents of the organism that are normally tolerated by the immune system of that organism. Autoimmune reactions can be either cell- or antibody-mediated. Autoantibodies are therefore antibodies that recognize normally tolerated cell and tissue constituents (or autoantigens). The antigenic specificity of an autoantibody can be a useful aid in clinical diagnosis. Autoantibodies are either cell (or tissue) specific, as found in organ-specific autoimmune diseases such as autoimmune thyroiditis, or non–organ-specific and reactive with ubiquitous intracellular antigens, as found in multisystem autoimmune diseases such as the systemic rheumatic diseases. The latter group includes autoantibodies that recognize components of macromolecular complexes of nucleic acids and/or proteins such as small nuclear ribonucleoprotein (snRNP) particles, nucleosomal and subnucleosomal structures, and tRNA synthetases, which are intrinsic components of all cell types present in an organism. Autoantibodies also recognize components of subcellular structures, including mitochondria, ribosomes, Golgi apparatus, nuclear membrane, and substructures within the nucleus and nucleolus. The ability of autoantibodies to recognize components of the cellular machinery of replication, transcription, RNA processing, RNA translation, and protein processing has made them important reagents for isolating cDNA clones that code for proteins involved in these cellular processes and for probing the relationship between molecular and cellular structure and function. The evolutionarily conserved nature of many autoantigens allows the use of autoantibodies to identify their target antigens in diverse species, ranging in some cases from humans to lower eukaryotes such as yeast. Autoantibodies have been used to inhibit the biological function of autoantigens and/or to recognize autoantigens in a defined functional state.
- Indirect Immunofluorescence (IIF)