AIM:To observe the changes of vitreous concentrations of cytokines in eyes with proliferative diabetic retinopathy(PDR)after intravitreal injection of ranibizumab or triamcinolone acetonide.

METHODS:A total of 88 PDR patients(112 eyes)with PDR from May 2015 to February 2017 in our hospital were enrolled in this study. The patients were randomly divided into ranibizumab group(57 eyes)and triamcinolone acetonide group(55 eyes). Ranibizumab(0.5mg/0.05mL)or triamcinolone acetonide(4mg/0.1mL)were given intravitreal respectively, after vitreous samples(0.5mL)were collected before the injection. Vitreous samples(0.5mL)were collected again 7d after the injection right before the PPV operation. The concentration of placental growth factor(PIGF)was measured by enzyme-linked immunosorbent assays(ELISA); the concentrations of monocyte chemotactic protein 1(MCP-1)and monocyte chemotactic protein 3(MCP-3), interleukin 6(IL-6)and interleukin 8(IL-8), platelet-derived growth factor-AB/BB(PDGF-AB/BB)and vascular endothelial growth factor-A(VEGF-A)were detected by Luminex200.

RESULTS:Afterranibizumab injection, the concentrations of PlGF and VEGF decreased significantly(PIGF:65.36±15.16 vs 19.42±6.34pg/mL; VEGF-A:315.16±14.34 vs 21.32±2.54 pg/mL, P<0.001), whereas those of IL-6, IL-8 increased significantly(IL-6:37.32±4.04 vs 52.42±5.32 pg/mL; IL-8:111.723±21.32 vs 198.73±19.03 pg/mL,P<0.001). There were no remarkable changes in MCP-1, MCP-3, and PDGF-AB/BB levels after ranibizumab injection(P>0.05). In triamcinolone acetonide group, the concentration of PIGF increased significantly after injection(74.28±17.34 vs 136.12±15.34 pg/mL,P<0.05), while that of MCP-1 decreased significantly(2789.32±143.54 vs 2038.21±105.34 pg/mL,P<0.05). There were no remarkable changes in the expression of MCP-3, IL-6, IL-8, PDGF-AB/BB and VEGF-A(P>0.05). In addition, the concentrations are lower for PIGF and VEGF-A(P<0.01)and higher for IL-8 and MCP-1(P<0.05)in eyes treated with ranibizumab, compared with those treated with triamcinolone acetonide. The incidence of intraoperative bleeding was significantly lower for ranibizumab group than that for triamcinolone acetonide group(P<0.05).

CONCLUSION: The levels of PIGF and VEGF-A decreased, while those of IL-6 and IL-8 increased in eyes with PDR after ranibizumab injection. After triamcinolone acetonide injection, the concentration of MCP-1 decreased, while that of PIGF increased.