Figure 4.

Interleukin-8 (CXCL8) expression and mRNA levels in synovial tissue (ST) from clinically uninvolved (CU) and from clinically involved (CI) joints in paired synovial biopsies from seven patients with rheumatoid arthritis (RA) (connected, filled circles). Also shown are results from one unpaired (open circles) synovial biopsy. CXCL8 levels are expressed as integrated optical density measured with digital image analysis on ST sections stained immunohistochemically and with in situ hybridization.