title: From nano to macro: studying the hierarchical structure of the corneal extracellular matrix.
abstract: In this review, we discuss current methods for studying ocular extracellular matrix (ECM) assembly from the 'nano' to the 'macro' levels of hierarchical organization. Since collagen is the major structural protein in the eye, providing mechanical strength and controlling ocular shape, the methods presented focus on understanding the molecular assembly of collagen at the nanometre level using X-ray scattering through to the millimetre to centimetre level using non-linear optical (NLO) imaging of second harmonic generated (SHG) signals. Three-dimensional analysis of ECM structure is also discussed, including electron tomography, serial block face scanning electron microscopy (SBF-SEM) and digital image reconstruction. Techniques to detect non-collagenous structural components of the ECM are also presented, and these include immunoelectron microscopy and staining with cationic dyes. Together, these various approaches are providing new insights into the structural blueprint of the ocular ECM, and in particular that of the cornea, which impacts upon our current understanding of the control of corneal shape, pathogenic mechanisms underlying ectatic disorders of the cornea and the potential for corneal tissue engineering.
authors.affiliation: Structural Biophysics Group, Cardiff Centre for Vision Science, School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Quantock
authors.affiliation: Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.
authors.forename: Moritz
authors.initials: M
authors.lastname: Winkler
authors.affiliation: Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.
authors.forename: Geraint J
authors.initials: GJ
authors.lastname: Parfitt
authors.affiliation: Structural Biophysics Group, Cardiff Centre for Vision Science, School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, UK.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Young
authors.affiliation: Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Brown
authors.affiliation: Structural Biophysics Group, Cardiff Centre for Vision Science, School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, UK.
authors.forename: Craig
authors.initials: C
authors.lastname: Boote
authors.affiliation: Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA. Electronic address: JJester@UCI.edu.
authors.forename: James V
authors.initials: JV
authors.lastname: Jester
mesh_terms: D003094:Collagen / Q000378:metabolism*; D003315:Cornea / Q000166:cytology* / Q000378:metabolism*; D005109:Extracellular Matrix / Q000378:metabolism*; D006801:Humans; D021621:Imaging, Three-Dimensional; D018613:Microscopy, Confocal / Q000379:methods; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D003094:Collagen
keywords: X-ray scattering; collagen; cornea; extracellular matrix; non-linear optical microscopy; second harmonic generation; structural biology
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