CDH11 and rheumatoid arthritis: <h4>Background</h4>The mechanisms underlying the progression of chronic inflammatory arthritis remain largely unclear.<h4>Methods</h4>We used single-cell mass cytometry on peripheral blood from patients with active rheumatoid arthritis (RA; n=11), psoriatic arthritis (PsA; n=12), and controls (n=9) to identify circulating cells co-expressing mesenchymal markers, including the homotypic adhesion molecule cadherin-11 (CDH11), and chemokine receptors.