“…Importantly, synovial aggregates derived from patients with OA typically express CD80. This inducible costimulatory ligand participates in T‐cell induction, signifying that such aggregates are zones of antigen detection and T‐cell activation (Keller et al, 2022). Studies have evidenced the critical role of Th1, Th9, and Th17 in OA pathogenesis (Lee et al, 2022).…”