Session Title: Vitreo Retinal Surgery I
Session Date/Time: Thursday 11/09/2014 | 08:00-10:00
Paper Time: 08:08
First Author: : J.A.Pournaras SWITZERLAND
Co Author(s): : T.J. Wolfensberger C. Salvisberg C. Fouda A. Hainard N. Turck
The occurrence of vitreoretinal disorders induces vascular and neuronal changes leading to the release of specific proteins that are be found in ocular fluids such as the vitreous body. We describe an extensive exploration of the vitreous proteome, which highlights new proteins involved in vitreoretinal diseases.
Jules-Gonin Eye Hospital, University of Lausanne, Switzerland
0.5 to 1.0 cc of native vitreous samples were collected at the beginning of surgery for rhegmatogenous retinal detachment (RRD), proliferative diabetic retinopathy (PRD) and controls. Different proteomics strategies including resin depletion, off-gel electrophoresis (OGE), gas phase fractionation (GPF) and isobaric labelling (tandem mass tag, TMT) experiments were applied. Quantitative experiments were performed in order to compare the vitreous of PRD and of control patients. Isobaric quantification was done using IsoQuant export (Easyprot software). Gene ontology (GO) category “biological process” (BP) was obtained using Uniprot knowledge database and DAVID bioinformatics resources 6.7 web-tool software. A BP was considered significant if the p-value was <0.05.
Combined proteomics analyses revealed more than 1650 identified proteins in the vitreous of RD patients. These proteins were mainly involved in cell and biological adhesion, acute inflammatory response, response to wounding and protein maturation. Among vitreous proteins which were differentially expressed between RDP and control patients, 10 proteins were particularly interesting. Fibrinogen beta and gamma chain, fibronectin, lipopolysaccharide-binding protein, monocyte differentiation antigen CD14, C4b protein binding alpha chain, vitamin K dependent protein C, haptoglobin- related protein and apolipoprotein B48 were significantly overexpressed in RDP vitreous (TMT ratio between 2.3 to 9.0, p-value <0.02). In addition, galectin 3-binding protein is the only protein to be underexpressed in RDP patients (TMT ratio: 0.64, p-value <0.02). All these proteins displayed a role in inflammation and protection processes.
Our results show that proteomics could be a useful tool for the study of proteins specifically modified in vitreoretinal disorders. In addition, with more than 1650 proteins identified, we expand the characterisation of the vitreous proteome markedly. This could open potentially new avenues for the diagnosis and a better understanding of the pathophysiological process taking place in retinal detachment and diabetic retinopathy.