Human Anti-Citrullinated Inter-Alpha-Trypsin Inhibitor Heavy Chain H3 Peptide Antibody Elisa Kit : in Vi Tro Diagnostics Kit of Autoimmune Rheumatic Diseases Examination

Autoimmune rheumatic diseases (ARDs) are chronic inflammatory disorders include rheumatoid arthritis (RA), Sj6gren’s syndrome (SS) and systemic lupus erythematosus (SLE), and so on. SS may occur alone (primary SS, pSS) or be associated with other systemic connective tissue diseases as secondary SS (sSS) such as RA-sSS and SLE-sSS. In previous study, we identify citrullinatd-inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3)542-556 peptide through concanavalin A (Con A) affinity chromatography, 1-D SDS-PAGE, and label-free nano-LC-MS/MS using pooled Con A-captured serum from RA-sSS female patients and age-matched healthy controls (HCs). We validate the levels of anti-citrullinatd-ITIH3542-556 peptide autoantibodies significantly increased in patients with RA, pSS, and RA-sSS compared to HCs. Autoantibody IgM and IgA against the citrullinated-ITIH3542-556 peptide have better detection in diagnosis of RA and RA-sSS, respectively. Particularly, autoantibody IgM against the citrullinated-ITIH3542-556 peptide showed better diagnostic performance in discriminating both RA versus pSS and pSS versus RA-sSS. The objective of the present study was to develop and determine the clinical performance of human anti-citrullinated-ITIH3542-556 peptide antibody detection in diagnosis of rheumatoid arthritis (RA) and secondary Sjogren's syndrome in rheumatoid arthritis (RA-sSS), as well as to compare commercially available anti-cyclic citrullinated peptide (anti-CCP) antibody enzyme-linked immunosorbent assay (ELISA) kits. In this study, the partial processes of ISO 13485 GMP were introduced to prepare reagents including in-coming quality control, precision, reproducibility, linearity, and interference of kit. This study also conducted a clinical trial; four hundred and seventy-five serum samples were tested with anti-citrullinated-ITIH3542-556 antibody kit and with generation three anti-cyclic citrullinated peptide (anti-CCP) IgG ELISA kit. Clinical performance of the kit was evaluated by validity and Reliability. Sensitivity, specificity, accuracy and agreement were assessed.