Inhibition of laser-induced choroidal neovascularization by anti-osteopontin antibody / 中华实验眼科杂志

ABSTRACT

Background It has been proved that as an important adhesion protein of extracellular matrix,osteopontion (OPN) can affect tumor neovascularization.Some new researches showed that anti-OPN antibody plays a role in regulating the neovascular vessel formation.Choroidal neovascularization (CNV) has the same structure with tumor neovascularization,but whether anti-OPN antibody restricts new vessel formation is unclear.Objective This study was to investigate the inhibitory effect of anti-OPN antibody on CNV.Methods Laser-induced CNV models were created in 40 eyes of 40 male SPF C57BL/6J mice by Argon laser photocoagulation of retinas,with the wavelength 514 nm.Thirty-six successful models were randomly divided into anti-OPN antibody group,mouse-IgG group and PBS group by the randomized number table.On the second day after photocoagulation,anti-OPN antibody of 400 μg was intraperitoneally injected in the anti-OPN antibody group,and the equivalent amount of mouse IgG and PBS were used in the same way in the mouse IgG group and PBS group.The CNV was evaluated by fundus fluorescein angiography (FFA) on the seventh days after photocoagulation.The mice were immediately sacrificed and the eyeballs were enucleated on the fourteenth day after photocoagulation,and 4 eyeballs in each group were used to observe the areas of CNV on the retinal pigmental epithelium-choroid-sclera fiat mounts,and the other 8 eyeballs of each groups were used to analyze the expression levels of OPN mRNA and vascular endothelial growth factor(VEGF) mRNA using quantitative fluorescence-PCR (QF-PCR).Results FFA showed fluorescein leakage areas around laser spots 7 days after photocoagulation,indicating that CNV appeared.The CNV areas were ([16.98±0.70] × 103) μm2,([27.13 ± 0.81] × 103) μm2 and ([35.39±2.14] ×103) μm2 respectively in the anti-OPN antibody group,mouse IgG group and PBS group,with a significant difference among the 3 groups (F =533.76,P =0.00),and the CNV area was significantly smaller in the anti-OPN antibody group compared with those of the mouse IgG group and PBS group (q =-3.95,-4.40,both at P＜0.05).No significant difference was found in the OPN mRNA expression between the antiOPN antibody group and mouse IgG group (t =-5.26,P =0.66).However,the expression of VEGF mRNA in choroidal tissue was significantly declined in the anti-OPN antibody group than that in the mouse IgG group (t =-6.74,P＜0.01).Conclusions Anti-OPN antibody suppresses the formation of CNV in laser-induced mouse model by down-regulating VEGF.