Inflammation and angiogenesis in osteoarthritis
Article first published online: 1 AUG 2003
Copyright © 2003 by the American College of Rheumatology
Arthritis & Rheumatism
Volume 48, Issue 8, pages 2173–2177, August 2003
How to Cite
Haywood, L., McWilliams, D. F., Pearson, C. I., Gill, S. E., Ganesan, A., Wilson, D. and Walsh, D. A. (2003), Inflammation and angiogenesis in osteoarthritis. Arthritis & Rheumatism, 48: 2173–2177. doi: 10.1002/art.11094
- Issue published online: 1 AUG 2003
- Article first published online: 1 AUG 2003
- Manuscript Accepted: 10 APR 2003
- Manuscript Received: 2 DEC 2002
- Droitwich Medical Trust
- Arthritis Research Campaign. Grant Numbers: W0584, D0541
- AstraZeneca Pharmaceuticals
To quantify the relationship between inflammation and angiogenesis in synovial tissue from patients with osteoarthritis (OA).
Hematoxylin and eosin staining and histologic grading for inflammation were performed for 104 patients who met the American College of Rheumatology criteria for OA and had undergone total joint replacement or arthroscopy. A purposive sample of synovial specimens obtained from 70 patients was used for further analysis. Vascular endothelium, endothelial cell (EC) proliferating nuclei, macrophages, and vascular endothelial growth factor (VEGF) were detected by immunohistochemical analysis. Angiogenesis (EC proliferation, EC fractional area), macrophage fractional area, and VEGF immunoreactivity were measured using computer-assisted image analysis. Double immunofluorescence histochemical analysis was used to determine the cellular localization of VEGF. Radiographic scores for joint space narrowing and osteophyte formation in the knee were also assessed.
Synovial tissue samples from 32 (31%) of 104 patients with OA showed severe inflammation; thickened intimal lining and associated lymphoid aggregates were often observed. The EC fractional area, EC proliferation, and VEGF immunoreactivity all increased with increasing histologic inflammation grade and increasing macrophage fractional area. In the synovial intimal lining, VEGF immunoreactivity was localized to macrophages and increased with increasing EC fractional area and angiogenesis. No inflammation or angiogenic indices were significantly correlated with radiographic scores.
Inflammation and angiogenesis in the synovium are associated with OA. The angiogenic growth factor VEGF generated by the inflamed synovium may promote angiogenesis, thereby contributing to inflammation in OA.