A Five-Gene Signature Identified by Integrating Single-Cell Analysis and Machine Learning Benchmarking Enables Rheumatoid Arthritis Diagnosis and Resveratrol Target Discovery

Background Rheumatoid arthritis (RA) is a systemic autoimmune disease featured by persistent synovial inflammation and multi-organ injury, with T lymphocytes as the core driver of its pathological progression. However, the molecular mechanisms of abnormal T cell functional regulation and the exact biological targets of resveratrol (a natural immunomodulatory polyphenol) in RA synovial microenvironment remain unclear. This study aimed to construct a T cell-focused RA diagnostic classifier and identify resveratrol-modulated molecular targets via multi-omics integration. Methods We integrated scRNA-seq and bulk transcriptome data of RA synovial tissues to characterize T cell-specific gene expression, intersected resveratrol targets from pharmacological databases with RA-related differentially expressed genes, and performed systematic benchmarking of 10 machine learning algorithms to screen stable diagnostic gene signatures (validated in external cohorts). CIBERSORT quantified synovial immune cell infiltration, and molecular docking evaluated resveratrol-target protein binding interactions. Results Distinct T cell subsets with differential resveratrol target gene expression were identified in RA synovium. A 5-gene signature ( PTTG1 , NUSAP1 , PDE4D , ITGA4 , BIRC3 ) was screened, showing excellent diagnostic performance (training cohort AUC = 0.983; external cohorts GSE55457 AUC = 0.908, GSE77298 AUC = 0.902). Its expression was positively correlated with activated T cell and pro-inflammatory macrophage infiltration. Molecular docking revealed stable binding of resveratrol to the five target proteins (binding free energy: -5.5 to -8.0 kcal/mol). Conclusion We constructed a robust T cell-centered 5-gene signature for RA diagnosis, and these five genes are potential molecular targets of resveratrol in RA immunotherapy. This study provides a novel molecular basis and research direction for developing synovitis-targeted therapeutic strategies for RA.