Abstract
Purpose :
To evaluate level of inflammatory cytokines and neurotrophins in vitreous samples of patients with idiopathic epiretinal membrane (iERM).
Methods :
Undiluted vitreous samples of patients with iERM undergoing pars plana vitrectomy (PPV) and membrane peeling were collected at the time of surgery (iERM group). For the control group, vitreous samples of patients undergoing PPV for macular hole, rhegmatogenous retinal detachment (without proliferative vitreoretinopathy), retained lens fragment, etc. were obtained. Patients with diabetic retinopathy or history of previous vitreoretinal surgery were excluded from the study. Cytometric Bead Array (CBA) system (BD, Heidelberg, Germany) was used to quantify levels of neurotrophins (including: Brain Derived Neurotrophic Factor (BDNF), Ciliary Neurotrophic Factor (CNTF), Nerve Growth Factor (NGF), Glial Cell Line Derived Neurotrophic Factor (GDNF), Neurotrophin-3 (NT3)) and inflammatory cytokines (IL-6, IL-8, IL-1b and TNF-a). Mann-Whitney U test (SPSS-16) was used for statistical analysis and p<0.0.5 was considered statistically significant.
Results :
Idiopathic ERM group consisted of 9 patients with an average age of 70 years (SD 3.6) and control group included 21 patients with an average age of 68.7 years (SD 8.2). Levels of NT3, GDNF and BDNF were significantly higher in patients with iERM compared to control group (p<0.05). No statistically significant difference was found in levels of NGF and CNTF. Down-regulation of IL-6 was noted in vitreous sample of patients in iERM group; however, this was not statistically significant (p=0.2). No statistically significant difference was seen in levels of IL-8, IL-1b and TNF-a between two groups.
Conclusions :
Glial cells, one of the main components of ERM, express high levels of neurotrophin receptors. It has previously been shown that neurotrophin GDNF plays a role in glial cell proliferation and ERM formation. Our results show for the first time that other neurotrophins (BDNF and NT3) are upregulated and involved in generation of iERM.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.