Reduced synovial membrane macrophage numbers, elam‐1 expression, and lining layer hyperplasia in psoriatic arthritis as compared with rheumatoid arthritis

Abstract

Our findings demonstrate important differences in the immunohistologic features of PA and RA SM: The PA SM is more vascular, ELAM-1 expression is less intense, and fewer macrophages invade the stroma and migrate to the lining layer than in RA SM: However, the lymphocytic infiltrate in the SM of both groups is similar.