Effect of adalimumab on experimental corneal neovascularization model

To evaluate the efficacy of adalimumab (ADA) on inhibition of experimental corneal neovascularization (CNV) and compare the outcomes with bevacizumab (BEVA).

Twenty-four female Winstar rats (48 eyes) were used. Silver/Potassium Nitrate sticks were used for creating CNV. Forty-eight eyes of the rats were separated into 6 groups. The eyes which only NaCl was injected subconjunctivally (SC) formed Group-1. The eyes which CNV was created and NaCl, BEVA (2.5 mg/0.05 mL), ADA (2.5 mg/0.05 mL), respectively, were injected SC formed group-2, 3 and 4. The eyes which only BEVA and ADA, respectively, were injected SC formed group-5 and 6. Five days later the animals were sacrificed. Hematoxylin and eosin staining, Masson trichrome staining, Vascular endothelial growth factor (VEGF), and Platelet-derived growth factor (PDGF) antibodies were performed.

Histochemical results showed that there was no histopathological finding in group-1, 5, and 6. Collagen fiber irregularity was observed in group-2 and there was a significant improvement in collagen fiber irregularity in group-3 and 4. Collagen fiber proliferation was higher in group-2 than in group-3 and 4. VEGF and PDGF stainings were not observed in group-1, 5, and 6. VEGF and PDGF stainings were observed in group-2 and significantly decreased in group-3 and 4 compared to group-2. ADA was found to be superior to BEVA in terms of decreasing VEGF staining.

Both BEVA and ADA were effective in inhibiting CNV. Subconjunctival ADA seems to be more effective than BEVA in terms of inhibiting VEGF expression. Further experimental studies about ADA and BEVA are needed.