Intravenous administration of anti-vascular endothelial growth factor humanized monoclonal antibody bevacizumab improves articular cartilage repair.
BACKGROUND
In this study, we investigate the efficacy of repairing an osteochondral defect in rabbit knee joints by administering bevacizumab, a humanized monoclonal anti-vascular endothelial growth factor (VEGF) antibody.


METHODS
An osteochondral defect was created on the patellar groove of 20 Japanese white rabbits that were classified into two recipient groups: group B, administration of bevacizumab (100-mg intravenous injection on the day of surgery and 2 weeks later), and a control group (defect only). Rabbits were killed 1 and 3 months postoperatively. Sections were stained with safranin O. Repair sites were evaluated using the modified O'Driscoll International Cartilage Repair Society grading system. The expression of chondromodulin (ChM)-I and VEGF was evaluated using immunohistochemical analyses.


RESULTS
At 1 month postoperatively, the repair site in group B was filled with cartilaginous tissue. At 3 months, the repair site retained this cartilage phenotype. At 1 month in the controls, the defects were mainly filled with fibrous tissue. At 3 months, the defect was replaced by fibrous tissue and bone. Over the 3-month period, histological scores were significantly higher in group B than in the controls. At 1 month, group B showed intense positive results for ChM-I in the bottom of the repair tissue. VEGF was also identified in the same area. In the controls, no ChM-I was observed in the repair tissue. Conversely, the remodeling hypertrophic chondrocyte layer stained intensely for VEGF.


CONCLUSIONS
Intravenous administration of bevacizumab contributes to better repair of articular cartilage in an osteochondral defect model. We suggest the possibility of facilitating articular cartilage repair with anti-VEGF antibody rather than using cultured cells or artificial scaffolds.
Nagai
Toshihiro
T
Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan.
Sato
Masato
M
Kutsuna
Toshiharu
T
Kokubo
Mami
M
Ebihara
Goro
G
Ohta
Naoshi
N
Mochida
Joji
J
D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D002358:Cartilage, Articular / Q000187:drug effects* / Q000293:injuries / Q000473:pathology; D005260:Female; D007150:Immunohistochemistry; D007275:Injections, Intravenous; D007719:Knee Joint / Q000187:drug effects / Q000473:pathology; D011817:Rabbits; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab