Purpose
To characterize the vitreous cytokine, chemokine, and growth factor profiles in patients with increasing retinal ischemia.
Methods
This IRB-approved study retrospectively analyzed 81 undiluted vitreous samples obtained from patients undergoing pars plana vitrectomy by a single surgeon at Beth Israel Deaconess Medical Center from November 2010 to September 2012. The specimens underwent a Bio-Plex Pro Human Cytokine Assay to determine the levels of 34 proteins including chemokines, cytokines, non-inflammatory proteins, and growth factors. Specimens were divided into the following four groups based on whether the patient underwent: 1.) vitrectomy for epiretinal membrane peeling and/or macular hole with no history of diabetes (control group), 2) vitrectomy for epiretinal membrane peeling and/or macular hole with a history of diabetes (DM group), 3) vitrectomy for proliferative diabetic retinopathy (PDR group), and 4) vitrectomy for neovascular glaucoma (NVG group). Parametric and non-parametric analyses were performed using SPSS software comparing demographics, as well as protein levels between each group.
Results
There was no significant difference in age and gender between groups. Numerous proteins were noted to be significantly elevated comparing the control and DM group (G-CSF, sCD40L, Endoglin, IL-6, PlGF, VEGF-D), the DM and PDR group (leptin, IL-8, PlGF, VEGF-A), as well as the DM to NVG group (G-CSF, leptin, TIE-2, sCD40L, EGF, HB-EGF, IL-6, IL-8, PlGF, TNF-alpha). Of note, placental growth factor (PlGF) exhibited a significant increase in all the aforementioned comparisons. Most proteins elevated in the PDR and NVG groups were significantly elevated compared to the control group as well.
Conclusions
Both angioproliferative growth factors as well as inflammatory proteins are elevated in eyes with severe retinal ischemia. We found that vitreous levels of PlGF increase significantly in patients with worsening retinal ischemia.
Keywords: 490 cytokines/chemokines •
572 ischemia •
688 retina