Persistent Secretion of MCP-1 in Vitreous after Successful Vitrectomy in Patients with Proliferative Diabetic Retinopathy

Abstract

Purpose: : The purpose of this study was to determine whether vitrectomy alters the concentration of monocyte chemotactic protein-1 (MCP-1), in the vitreous of eyes with proliferative diabetic retinopathy (PDR).

Methods: : We measured the levels of MCP-1 and vascular endothelial growth factor (VEGF) by sandwich enzyme linked immunosorbent assay (ELISA) in vitreous samples from 39 eyes of 33 patients with PDR before pars plana vitrectomy (without IOL implantation) and 39 fluid samples from the same 33 patients obtained during an IOL implantation 3.1 to 25.7 (mean 6.7) months after an earlier vitrectomy. The levels of those factors were also measured in 32 eyes of 32 patients that had undergone macular hole (MH) surgeries.

Results: : The mean vitreous levels of MCP-1 (957.3 pg/ml) and VEGF (964.9 pg/ml) in the samples collected before the vitrectomy were significantly higher in patients with PDR than in the control patients (P <0.01). The levels of VEGF (292.5 pg/ml) in the samples from eyes with PDR collected at the time of the IOL implantation were significantly lower than that collected before the vitrectomy (P <0.01). In contrast, the changes in the levels of MCP-1 were not significant after vitrectomy. The MCP-1 level in the vitreous fluid from patients with PDR was not correlated with the interval between the initial vitrectomy and the secondary IOL implantation.

Conclusions: : An absence of a significant change in the intravitreal concentration of MCP-1 and the significant decrease in VEGF indicates MCP-1 may play a role in inciting inflammation even after successful vitrectomy in the vitreous of patients with PDR.

Keywords: vitreoretinal surgery • inflammation • diabetic retinopathy