Effects of topical and subconjunctival bevacizumab in high-risk corneal transplant survival.
OBJECTIVE
To investigate whether corneal graft survival could be improved by topical or subconjunctival bevacizumab in a murine model of vascularized high-risk corneal transplantation.


METHODS
Before corneal transplantation, intrastromal sutures were placed for 2 weeks in the corneas of BALB/c mice, inducing intense angiogenesis. Allogeneic corneal transplantation was performed using C57BL/6 donor mice. Topical bevacizumab (2.5%) was delivered 3 times a day for 3 weeks in one treatment group, and 0.02 mL (0.5 mg) bevacizumab was injected subconjunctivally at days 0, 4, 8, and 15 after transplantation in the other treatment group. The control group received no treatment. Grafts were examined twice a week for 8 weeks by slit-lamp microscopy and were photographed once a week by slit-lamp digital camera and scored for opacity. For assessment of corneal neovascularization (NV), a quantitative method was used to measure three primary metrics including neovascular area, vessel caliber, and neovessel invasion area.


RESULTS
Both topical and subconjunctival bevacizumab treatment reduced neovascular area and vessel caliber; however, the regression of corneal NV was more profound when treated subconjunctivally. The mean percentage reduction of neovascular area was 55% (P < 0.05) by week 8 in the subconjunctival treatment group and 33% (P = 0.15) in the topical group. Only subconjunctival bevacizumab treatment resulted in significant regression of neovessel invasion area (P < 0.05). All corneal transplants in both the control and the topical groups were rejected by 4 weeks after transplantation. However, in the subconjunctival treatment group, 33% of corneal grafts survived (P < 0.01).


CONCLUSIONS
Subconjunctival bevacizumab may offer an adjunctive measure to conventional therapies in preventing graft rejection in high-risk corneal transplantation.
Dastjerdi
Mohammad H
MH
Schepens Eye Research Institute, Boston, MA 02114, USA.
Saban
Daniel R
DR
Okanobo
Andre
A
Nallasamy
Nambi
N
Sadrai
Zahra
Z
Chauhan
Sunil K
SK
Hajrasouliha
Amir R
AR
Dana
Reza
R
D000287:Administration, Topical; D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D003228:Conjunctiva; D016510:Corneal Neovascularization / Q000473:pathology / Q000517:prevention & control* / Q000601:surgery*; D016039:Corneal Transplantation; D004195:Disease Models, Animal; D006085:Graft Survival / Q000187:drug effects*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012307:Risk Factors; D014184:Transplantation, Homologous; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab