title: Proteome profiling of corneal epithelium and identification of marker proteins for keratoconus, a pilot study.
abstract: The purpose of this study is to identify corneal proteins differentially expressed between keratoconus and normal epithelial samples. Proteins from the corneal epithelium were isolated from 6 keratoconus and 6 myopia patients (controls) and separated by 2D-gel electrophoresis. Six % and 12% SDS-PAGE gels were used to separate low and high molecular weight proteins. Gels were silver stained and protein spots were defined by Melanie II software. The proteins that were most altered in expression comparing keratoconus and controls were extracted, trypsin-digested, and identified by mass spectroscopy. Approximately 200-500 protein spots were detected on each gel. Nineteen spots were identified as differentially expressed between keratoconus and reference epithelium including cytokeratin 3 (< 7.8 fold), gelsolin (1.6 fold), S100A4 (1.9 fold), and enolase 1 (0.72 fold). Another identified protein found at very high levels was cytokeratin 12. Gelsolin, cytokeratin 3, and cytokeratin 12 have previously been described to be involved in other corneal diseases. Three proteins, gelsolin, alpha enolase, and S100A4 were identified to be differentially expressed in keratoconus compared to reference epithelium and thus may be involved in the pathogenesis.
authors.affiliation: Molecular Diagnostic Laboratory, Skejby Sygehus, Brendstrupgaarsvej, 8200 Aarhus N, Denmark. nikim@as.aaa.dk
authors.forename: Kim
authors.initials: K
authors.lastname: Nielsen
authors.forename: Henrik
authors.initials: H
authors.lastname: Vorum
authors.forename: Per
authors.initials: P
authors.lastname: Fagerholm
authors.forename: Karin
authors.initials: K
authors.lastname: Birkenkamp-Demtröder
authors.forename: Bent
authors.initials: B
authors.lastname: Honoré
authors.forename: Niels
authors.initials: N
authors.lastname: Ehlers
authors.forename: Torben F
authors.initials: TF
authors.lastname: Orntoft
mesh_terms: D015415:Biomarkers / Q000032:analysis; D016022:Case-Control Studies; D015180:Electrophoresis, Gel, Two-Dimensional; D019573:Epithelium, Corneal / Q000737:chemistry*; D005136:Eye Proteins / Q000235:genetics*; D018260:Gelsolin / Q000235:genetics; D020869:Gene Expression Profiling; D006801:Humans; D007633:Keratins / Q000235:genetics; D007640:Keratoconus / Q000175:diagnosis* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010751:Phosphopyruvate Hydratase / Q000235:genetics; D010865:Pilot Projects; D040901:Proteomics; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D015415:Biomarkers; D005136:Eye Proteins; D018260:Gelsolin; D000071999:S100 Calcium-Binding Protein A4; D009418:S100 Proteins; C077591:S100A4 protein, human; D007633:Keratins; D010751:Phosphopyruvate Hydratase