Based on H&E and immunohistochemistry staining for CD3 (T cells), CD20 (B cells), CD138 (plasma cells), and CD68 (macrophages), synovial tissue from each UA and definite arthritis group was categorized into three distinct synovial pathotypes: lympho-myeloid, diffuse-myeloid, and pauci-immune (37). The gene discussed is SDC1; the disease is arthritic joint disease.