Abstract
Purpose :
High myopia significantly increases the possibility of developing a variety of retinal complications, leading to severe vision loss. To offer clues of pathogenic mechanisms related to high myopia, we compared the vitreous humor proteome between patients with high myopia and idiopathic macular hole (MH).
Methods :
Vitreous humor samples were obtained from patients with highly myopic MH (n=5) and idiopathic MH (n=5) during pars plana vitrectomy. Samples were digested and mixed with internal standards, Universal Proteomics Dynamic Range Standard (UPS2) peptides. Mixtures were then analyzed by nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS). Label-free quantification and intensity-based absolute quantification (iBAQ) were employed for protein quantification. We identified differential expressed proteins (abundance ratio > 1.5) by bioinformatic analysis. Western blot was performed to validate the differential expressions of representative proteins.
Results :
An average of 461 proteins were identified and quantified per sample. Comparative analysis revealed 83 differential expressed proteins. Among these, the abundance of 48 and 35 proteins were significantly higher and lower in high myopia compared with controls. Extracellular region was the component in which most of the specific subset of proteins located. Biological pathway analysis suggested that most of the differentially expressed proteins were related to complement and coagulation cascades, inflammatory responses, extracellular matrix-receptor interaction and focal adhesion. The differential expressions of opticin, apolipoprotein A1 and complement C1q were confirmed by Western blot.
Conclusions :
This study reveals the differences in the composition of vitreous proteins between high myopia and non-myopia. Changes of biological pathways, including complement activation, may involve in the pathogenesis of high myopia. The identification of the key proteins could be important for the development of prognosis and intervention.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.