Abstract
Purpose :
Proliferative vitreoretinopathy (PVR) is a challenging pathologic process that contributes to suboptimal visual outcomes in patients with retinal detachment. The purpose of this study was: (1) to assess whether quantitative protein analysis of vitreous fluid in human eyes of patients with PVR with retinal re-detachment was feasible, and (2) whether significant changes in protein levels occur in vitreous from eyes with PVR compared with that of controls.
Methods :
Undiluted vitreous samples were obtained during routine pars plana vitrectomy surgery under an IRB-approved protocol from the eyes of two patients (age 30 and 48; PVR grade B and C, respectively) who developed recurrent retinal detachment with PVR. These were compared to undiluted vitreous samples of two eye bank specimens without prior retinal detachment or other vitreoretinal disease. Vitreous samples were labeled with iTRAQ reagent and analyzed by liquid chromatography and tandem mass spectrometry on an Orbitrap type device. Bioinformatics analyses were performed using the Proteome Discoverer software suite.
Results :
A total of 107 proteins were identified in the vitreous of eyes with PVR compared to controls. We further classified the proteins according to biological process activity, revealing that proteins were active in regulation of biological processes, response to stimulus, and cell organization and biogenesis (44, 44, and 25 proteins respectively). The protein functions included protein binding, catalytic activity, metal ion binding, and enzyme regulator activity (87, 39, 25 and 20 proteins respectively). The most frequent up-regulated proteins (with respect to presence in donors) in PVR vitreous compared to control with the highest peptide number and sequence coverage were EFEMP1, TF, IGHG4, APOE, and IGHM. Similarly, the most frequent down-regulated PVR vitreous proteins were FABP1, CRYBA1, ENO1, CRYBB2, and PARK7.
Conclusions :
This study serves as a basis for future investigation of PVR with iTRAQ labeled mass spectrometric analyses. Our current study has identified candidate proteins for investigation into their potential role in PVR. Further sample collection and multidisciplinary biomedical research in the future will point out their role in PVR.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.