Fig. 2

a–f IHC staining for CD3/CD20 on ST of patients with naïve or MTX-IR PsA and Ab^neg RA patients. Example photos of CD3 (RED)/CD20 (DAB) staining of ST biopsies from patients with naïve (a) or MTX-IR (b) PsA patients and with naïve (c) or MTX-IR (d) Ab^neg RA patients (magnification × 20 and magnification × 40 in the corresponding inset). Thin black arrows indicate CD3⁺ cells (red), and black arrow heads indicate CD20⁺ cells (brown) in the corresponding inset. e IHC scores for CD20⁺ cells in PsA and Ab^neg RA patients divided by treatment regimen. f IHC scores for CD3⁺ cells in PsA and Ab^neg RA patients divided by treatment regimen. IHC immunohistochemistry, PsA psoriatic arthritis, RA rheumatoid arthritis, Ab autoantibody, MTX-IR methotrexate inadequately responder, CD cluster designation