title: Beyond citrullination: other post-translational protein modifications in rheumatoid arthritis.
abstract: The presence of autoantibodies is one of the hallmarks of rheumatoid arthritis (RA). In the past few decades, rheumatoid factors (autoantibodies that recognize the Fc-tail of immunoglobulins) as well as anti-citrullinated protein antibodies (ACPAs) have been studied intensively. ACPAs recognize post-translationally modified proteins in which the amino acid arginine has been converted into a citrulline. More recently, other autoantibody systems recognizing post-translationally modified proteins have also gained attention, including autoantibodies recognizing fragmented immunoglobulin (anti-hinge antibodies), autoantibodies recognizing acetylated proteins and autoantibodies recognizing proteins that are modified by adducts formed under oxidative stress. In particular, detailed insights have been obtained on the presence and properties of autoantibodies recognizing carbamylated proteins, commonly called anti-carbamylated protein (anti-CarP) antibodies. In this Review, we summarize the current knowledge relating to these emerging autoantibodies that recognize post-translationally modified proteins identified in RA, with an emphasis on anti-CarP antibodies.
authors.affiliation: Department of Rheumatology, C1R, Leiden University Medical Center, Albinusdreef 2, Postbus 9600, 2300 RC Leiden, Netherlands.
authors.forename: Leendert A
authors.initials: LA
authors.lastname: Trouw
authors.affiliation: Sanquin Research, Department of Immunopathology, Plesmanlaan 125, 1066 CX Amsterdam, Netherlands; Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, Netherlands.
authors.forename: Theo
authors.initials: T
authors.lastname: Rispens
authors.affiliation: Department of Rheumatology, C1R, Leiden University Medical Center, Albinusdreef 2, Postbus 9600, 2300 RC Leiden, Netherlands.
authors.forename: Rene E M
authors.initials: REM
authors.lastname: Toes
mesh_terms: D000107:Acetylation; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D001323:Autoantibodies / Q000502:physiology; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008315:Malondialdehyde / Q000276:immunology; D011499:Protein Processing, Post-Translational / Q000276:immunology
chemical_list: D001323:Autoantibodies; D008315:Malondialdehyde