Proteomic Analysis of Vitreous Humor in Retinal Vein Occlusion

PLoS One. 2016 Jun 30;11(6):e0158001. doi: 10.1371/journal.pone.0158001. eCollection 2016.

Abstract

Purpose: To analyze the protein profile of human vitreous of untreated patients with retinal vein occlusion (RVO).

Methods: Sixty-eight vitreous humor (VH) samples (44 from patients with treatment naïve RVO, 24 controls with idiopathic floaters) were analyzed in this clinical-experimental study using capillary electrophoresis coupled to mass spectrometer and tandem mass spectrometry. To define potential candidate protein markers of RVO, proteomic analysis was performed on RVO patients (n = 30) and compared with controls (n = 16). To determine validity of potential biomarker candidates in RVO, receiver operating characteristic (ROC) was performed by using proteome data of independent RVO (n = 14) and control samples (n = 8).

Results: Ninety-four different proteins (736 tryptic peptides) could be identified. Sixteen proteins were found to be significant when comparing RVO and control samples (P = 1.43E-05 to 4.48E-02). Five proteins (Clusterin, Complement C3, Ig lambda-like polypeptide 5 (IGLL5), Opticin and Vitronectin), remained significant after using correction for multiple testing. These five proteins were also detected significant when comparing subgroups of RVO (central RVO, hemi-central RVO, branch RVO) to controls. Using independent samples ROC-Area under the curve was determined proving the validity of the results: Clusterin 0.884, Complement C3 0.955, IGLL5 1.000, Opticin 0.741, Vitronectin 0.786. In addition, validation through ELISA measurements was performed.

Conclusion: The results of the study reveal that the proteomic composition of VH differed significantly between the patients with RVO and the controls. The proteins identified may serve as potential biomarkers for pathogenesis induced by RVO.

MeSH terms

  • Biomarkers / metabolism
  • Electrophoresis, Capillary
  • Female
  • Humans
  • Male
  • Proteomics / methods*
  • Retinal Vein Occlusion / diagnosis*
  • Retinal Vein Occlusion / metabolism
  • Retrospective Studies
  • Tandem Mass Spectrometry
  • Vitreous Body / metabolism*

Substances

  • Biomarkers

Grant support

The research group was supported by the Adolf Messer Stiftung, Königstein, Hessen, Germany. Parts of this research were supported by a research grant from Bayer Vital GmbH, Leverkusen, Germany. Michael Reich is a recipient of scholarships from the Studienstiftung des deutschen Volkes and the Dr. Gabriele Lederle-Stiftung. He wants to thank these organizations for their support. Matthias Nobl is a recipient of scholarships from the PRO RETINAStiftung zur Verhütung von Blindheit and the Dr. Gabriele Lederle-Stiftung. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Mosaiques diagnostics GmbH provided support in the form of salaries for authors [JS], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.