Core Viewpoint - The article discusses a significant advancement in the identification of citrullinated proteins, which are crucial autoantigens in rheumatoid arthritis (RA), through the development of the Iseq-Cit technology, enabling precise analysis with minimal sample requirements [2][4]. Group 1: Research Development - The research team from Sichuan University West China Hospital published a study in Nature Biomedical Engineering, introducing the Iseq-Cit technology for analyzing citrullinated proteomes in normal individuals, high-risk RA individuals, and RA patients [3]. - The study established a correlation between disease activity and citrullination, confirming that certain citrullinated peptides have potential for early diagnosis and predicting drug treatment responses [3][4]. Group 2: Methodology and Findings - Iseq-Cit technology allows for high-throughput quantitative analysis of citrullinome using less than 1% of the sample volume required by traditional methods, focusing on longitudinal cohorts of high-risk RA individuals and patients [7]. - The research found that the plasma citrullinated proteome profile is closely related to the progression and severity of RA, leading to the development of a predictive model integrating clinical indicators and citrullination data [7]. Group 3: Predictive Model and Accuracy - A BiGRU model was trained using 67,399 RA serum-negative peptides and 8,816 RA serum-positive peptides to assess the serum reactivity of identified citrullinated peptides, achieving an accuracy of 84.2% in predicting serum reactivity [7]. - The model successfully identified 19 potential diagnostic biomarkers for RA, showcasing the innovative approach to autoantigen discovery and treatment stratification [8].