title: Proteomic Analysis of Embryonic and Young Human Vitreous.
abstract: OBJECTIVE
  The proteomic profile of vitreous from second-trimester human embryos and young adults was characterized using mass spectrometry and analyzed for changes in protein levels that may relate to structural changes occurring during this time. This vitreous proteome was compared to previous reports to confirm proteins already identified and reveal novel ones.
  
  
  METHODS
  Vitreous from 17 human embryos aged 14 to 20 weeks gestation (WG) and from a 12-, a 14-, a 15-, and a 28-year-old was individually analyzed using tandem mass spectrometry-based proteomics. Peptide spectral count associations with embryonic age were assessed using a general linear model of fold changes and Spearman's rank correlation. Differences between embryonic and young adult vitreous proteomes were also compared. Immunohistochemistry was used to evaluate three proteins in five additional fetal (10-18 WG) human eyes.
  
  
  RESULTS
  There were 1217 proteins identified in fetal and young adult human vitreous, 206 after quantile normalization and variance filtering. In embryos, the peptide counts of 37 proteins changed significantly from 14 to 20 WG: 75.7% increased, 24.3% decreased. Immunohistochemistry confirmed the absence of clusterin and cadherin in 10 and 14 WG eyes and their presence at 18 WG. Comparing embryonic to young adult vitreous, 47 proteins were significantly higher or lower. A total of 768 proteins not previously identified in the literature are presented.
  
  
  CONCLUSIONS
  Proteins previously unreported in the human vitreous were identified. The human vitreous proteome undergoes significant changes during embryogenesis and young adulthood. A number of protein levels change considerably during the second trimester, with the majority decreasing.
authors.affiliation: VMR Institute for Vitreous Macula Retina, Huntington Beach, California, United States 2Doheny Eye Institute, Los Angeles, California, United States.
authors.forename: Kenneth M P
authors.initials: KM
authors.lastname: Yee
authors.affiliation: Beetham Eye Institute, Joslin Diabetes Center, Boston, Massachusetts, United States.
authors.forename: Edward P
authors.initials: EP
authors.lastname: Feener
authors.affiliation: School of Optometry and Vision Science, University of New South Wales, Sydney, Australia 5Save Sight Institute, University of Sydney, Sydney, Australia.
authors.forename: Michele
authors.initials: M
authors.lastname: Madigan
authors.affiliation: Department of Medicine Statistics Core, David Geffen School of Medicine at UCLA, Los Angeles, California, United States.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Jackson
authors.affiliation: Beetham Eye Institute, Joslin Diabetes Center, Boston, Massachusetts, United States.
authors.forename: Ben-Bo
authors.initials: BB
authors.lastname: Gao
authors.affiliation: Doheny Eye Institute, Los Angeles, California, United States.
authors.forename: Fred N
authors.initials: FN
authors.lastname: Ross-Cisneros
authors.affiliation: John Curtin School of Medical Research, Canberra, Australia 8Australian National University, Canberra, Australia.
authors.forename: Jan
authors.initials: J
authors.lastname: Provis
authors.affiliation: Beetham Eye Institute, Joslin Diabetes Center, Boston, Massachusetts, United States 9Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Lloyd Paul
authors.initials: LP
authors.lastname: Aiello
authors.affiliation: Doheny Eye Institute, Los Angeles, California, United States 10Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, United States.
authors.forename: Alfredo A
authors.initials: AA
authors.lastname: Sadun
authors.affiliation: VMR Institute for Vitreous Macula Retina, Huntington Beach, California, United States 2Doheny Eye Institute, Los Angeles, California, United States.
authors.forename: J
authors.initials: J
authors.lastname: Sebag
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002853:Chromatography, Liquid; D003430:Cross-Sectional Studies; D005136:Eye Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D011247:Pregnancy; D040901:Proteomics / Q000379:methods*; D014822:Vitreous Body / Q000737:chemistry* / Q000166:cytology / Q000196:embryology; D055815:Young Adult
chemical_list: D005136:Eye Proteins