Supplementary Material for: Analyzing the Role of Specific DAMPs-Related Genes in Osteoarthritis and Investigating the Association Between β-Amyloid and ApoE Isoforms

Introduction：Osteoarthritis (OA) is a prevalent chronic joint disorder. It is characterized by an immune response that maintains a low level of inflammation throughout its progression. During OA, cartilage degradation leads to the release of damage-associated molecular patterns (DAMPs), which intensify the inflammatory response. β-amyloid, is a well-recognized DAMP in OA, can interact with APOE isoforms. Methods：This study identified DAMPs-related genes in OA using bioinformatics techniques. Additionally, we examined the expression levels of β-amyloid and ApoE isoforms by ELISA. Results: We identified 10 key genes by machine learning techniques. Immune infiltration analysis revealed upregulation of various immune cell types in OA cartilage, underscoring the critical role of inflammation in OA pathogenesis. In the validation study, elevated serum levels of β-amyloid in Knee Osteoarthritis (KOA) patients were confirmed, showing positive correlations with APOE2 and ApoE4. Notably, ApoE3 was identified as an independent protective factor against KOA. Conclusion: In this bioinformatics analysis, we identified the DAMPs-related genes of KOA, and explored their potential functions and regulatory networks. The high expression of β-Amyloid in KOA was confirmed by experiments, and the correlation between βAmyloid and ApoE2, ApoE4 in KOA was revealed for the first time, this provides a new way to explore the pathogenesis of KOA and to study the therapeutic targets of KOA.