Abstract
Purpose: :
CD40 is one of the co-stimulatory molecules, and interacts with its ligand, CD40L expressed on activate T lymphocytes. Recent study demonstrated that not only lymphocytes but also vascular endothelial cells express CD40. In this study, we investigated whether costimulatory signals via CD40/CD40L pathway were involved in corneal angiogenesis using the mouse model of suture-induced corneal neovascularization.
Methods: :
One suture with 10-0 nylon was placed intrastromally and suture was left in place for 7 days. Seven days after the placement, the corneas were excised and analyzed for expression of CD40 and CD40L by RT-PCR and immunohistochemistry. Some groups of mice received agonistic anti-CD40 mAb (FGK45) intraperitoneally on day 0, 3, and 5 after the suture placement. Control mice received equal volume of rat isotype IgG. In addition, anti-lectin-FITC antibody was injected intravenously 7 days after suture placement, and extension of blood vessels on the cornea was numerically measured using software of NIH image.
Results: :
Expression of CD40 was observed in the vascularized corneas but not in intact corneas, which was also verified by mRNA expression of CD40. Administration of agonistic anti-CD40 mAb significantly progressed corneal neovascularization compared with control Rat IgG treatment. On the other hand, expression of CD40L was not observed in the vascularized corneas by either RT-PCR nor immunohistochemistry.
Conclusions: :
CD40 molecule is expressed on the vasculized cornea, which delivers costimulatory signals involved in progression of corneal neovascularization.
Keywords: neovascularization • cornea: basic science