The DEK protein, encoded by the *DEK* gene, is a chromatin-associated protein involved in DNA replication, RNA splicing, and epigenetic regulation. It plays roles in maintaining genomic stability and modulating transcriptional activity. DEK antibodies, primarily detected in autoimmune diseases, are most notably associated with systemic lupus erythematosus (SLE). These autoantibodies target the DEK protein, leading to its recognition in serum through assays like ELISA or immunoblotting.
First identified in the 1990s, DEK antibodies are present in approximately 10-20% of SLE patients, often correlating with specific clinical features such as photosensitivity, arthritis, or renal involvement. Their presence is also reported in other conditions, including juvenile idiopathic arthritis, rheumatoid arthritis, and certain cancers, though their pathogenic role remains unclear. In SLE, DEK antibodies may contribute to disease mechanisms by forming immune complexes or interfering with DEK's normal functions, such as DNA repair.
Research suggests DEK itself can be secreted by activated immune cells, potentially enhancing its immunogenicity. Despite their diagnostic utility, DEK antibodies are not exclusive to SLE and are not included in formal classification criteria. Ongoing studies aim to clarify their role in disease progression and their potential as therapeutic targets or biomarkers for monitoring disease activity.