Peptidyl arginine deiminase type 2 (PAD‐2) and PAD‐4 but not PAD‐1, PAD‐3, and PAD‐6 are expressed in rheumatoid arthritis synovium in close association with tissue inflammation

Abstract

PAD-2 and PAD-4 are the only PAD isotypes expressed in the ST of patients with RA and those with other arthritides. Inflammatory cells are a major source, but PAD-4 also comes from hyperplastic synoviocytes. Both isotypes are probably involved in the citrullination of fibrin.