Interleukin-13 and age-related macular degeneration

AIM：To identify the effects of interleukin（IL）-13 on retinal pigment epithelial（RPE） cells and the IL-13 level in aqueous humor of age-related macular degeneration（AMD） patients.METHODS：IL-13 levels in aqueous humor specimens from AMD patients were detected with enzyme-linked immunosorbent assay（ELISA）.ARPE-19 cells were treated with 10 ng/m L IL-13 for 12,24,and 48 h.The cell proliferaton was evaluated by the MTS method.The m RNA and protein levels of α-SMA and ZO-1 were evaluated with quantitative real-time polymerase chain reaction（q RT-PCR） and Western blot respectively.The expression of tumor necrosis factor-α（TNF-α）,transforming growth factor-β（TGF-β） and vascular endothelial growth factor（VEGF） were assessed by ELISA.RESU LTS：IL-13 levels in the aqueous humor of patients with AMD were significantly higher than those in the control（167.33±17.64 vs 27.12±5.65 pg/m L;P〈0.01）.In vit ro,IL-13 of high concentrations（10,15,and 20 ng/m L） inhibited ARPE-19 cell proliferation.α-SMA m RNA in ARPE-19 cell were increased（1.017±0.112 vs 1.476±0.168;P〈0.001） and ZO-1 decreased（1.051±0.136 vs 0.702±0.069;P〈0.001） after treated with 10 ng/m L IL-13 for 48 h.The protein expression of α-SMA and ZO-1 also showed the same tendency（α-SMA：P=0.038;ZO-1：P=0.008）.IL-13 significantly reduced the level of TNF-α（44.70±1.67 vs 31.79±3.53 pg/m L;P=0.005） at 48 h,but the le vel of TGF-β2 was significantly increased from 34.44±2.92 to 57.61±6.31 pg/m L at 24h（P=0.004） and from 61.26±1.11 to 86.91±3.59 pg/m L at 48h（P〈0.001）.While expressions of VEGF didn＇t change after IL-13 treatment.CONCLUSION：IL-13 in vitr o inhibit ARPE-19 cell proliferation and expression in the aqueous may be associated with AMD.