Antinuclear antibodies: A contemporary nomenclature using HEp-2 cells Allan S. Wiik a, * , Mimi Høier-Madsen a , Jan Forslid b , Peter Charles c , Jan Meyrowitsch d a Department of Clinical Biochemistry and Immunology, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark b Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital, 171 76 Stockholm, Sweden c Translational Research, Kennedy Institute of Rheumatology, Imperial College London, 65 Aspenlea Road, London W6 8LH, United Kingdom d Percepton Ltd., Rialtovej 12, 2300 Copenhagen S, Denmark Keywords: Nomenclature Standardization HEp-2 cells Consensus formation Medical training ANA abstract The choice of terms used to describe indirect immunofluorescence (IIF) staining patterns of autoanti- bodies binding to HEp-2 cells is at present quite varied and disordered because no accurate consensus on names and descriptions exist. The aim of our study was to propose a logical and ordered IIF classification taxonomy based on 29 different selected IIF patterns. In a preliminary project carried out at Statens Serum Institut it was first shown by use of a software programme named DOORS developed by Percepton Ltd, that reading of digitized images of HEp-2 patterns on an LCD monitor could be used instead of traditional microscopy. Digitized images of HEp-2 patterns were then used in the EU supported project named CANTOR (June 1998eJuly 2000) aiming to reach consensus among three clinical immunology expert centres and collaborating to attain a classification version that could be used to qualitatively and quantitatively test and train image recognitions skills of laboratory technicians against expert consensus. The usability of this classification version was then tested in a course consisting of training and certi- fication. The conclusion was that participants in the training programme clearly increased their perceptive skills using images, terms, descriptions and the graphic and statistic tools in the self- administered DOORS programme and that software-assisted training could achieve a common and accurate level of visual pattern interpretation. All results from this project were reported to the European Commission but have not previously been published in scientific literature. This communication presents the final results of agreed image classifications. Ó 2010 Elsevier Ltd. All rights reserved. 1. Introduction Antinuclear autoantibodies (ANA) are clinically useful markers of certain chronic immuno-inflammatory diseases. The indirect immunofluorescence technique (IIF) used to detect ANA was described already in 1958 by Friou et al. [1] and IIF has become the standard method to screen for presence of ANA in patient sera. The use of tumor cell lines e.g. the laryngeal carcinoma cell line HEp-2 cells (ATCC-CCL 23) is now the preferred cell substrate for IIF demonstration of ANA [2e4]. Though this paper deals with detec- tion of ANA, it will also deal with other autoantibodies visualized by HEp-2 cell staining. In the present review the term “ANA” will thus cover all antibodies binding to HEp-2 cells, though only some of them are sensu strictu directed to nuclear antigens. Since the 1980-ies the clinical potential of detecting a positive ANA in a patient serum has progressed from merely being a marker in support for diagnosis of an autoimmune condition to becoming part of agreed diagnostic or prognostic criteria for certain diseases similar to clinically well-defined manifestations [reviewed in 4,5]. ANA detected by IIF using HEp-2 cells are found in frequencies between 100 and 50% of patients with systemic lupus eryth- ematosus (SLE), systemic sclerosis (SSc), mixed connective tissue disease (MCTD), poly/dermato-myositis (PM/DM), Sjögren’s syndrome (SjS), Felty’s syndrome, drug-induced lupus-like disease, and juvenile chronic arthritis [5]. ANA directed to individual specific nuclear and cytoplasmic target molecules can be detected by a number of methods e.g. double immuno-diffusion, counter-immuno-electrophoresis, enzyme-linked immuno-sorbent assay (ELISA), antigen-specific Abreviations: ANA, antinuclear antibodies; ANCA, anti-neutrophil cytoplasm antibodies; DM, dermatomyositis; DOORS, discrete object observation recognition system; FITC, fluoresceine isothiocyanate; IIF, indirect immunofluorescence; LEDGF, lens epithelium-derived growth factor; MCTD, mixed connective tissue disease; PBC, primary biliary cirrhosis; PCNA, proliferating cell nuclear antigen; PM, poly- myositis; PML, promyelocytic leukemia; RNAP, RNA polymerase; RA, rheumatoid arthritis; SLE, systemic lupus erythematosus; SSc, systemic sclerosis. * Corresponding author at: Digesmuttevej 10, 2970 Hørsholm, Denmark. Tel.: þ45 45867915. E-mail address: asw@dadlnet.dk (A.S. Wiik). Contents lists available at ScienceDirect Journal of Autoimmunity journal homepage: www.elsevier.com/locate/jautimm 0896-8411/$ e see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.jaut.2010.06.019 Journal of Autoimmunity xxx (2010) 1e15 Please cite this article in press as: Wiik AS, et al., Antinuclear antibodies: A contemporary nomenclature using HEp-2 cells, Journal of Auto- immunity (2010), doi:10.1016/j.jaut.2010.06.019