title: Changes in tarsal plate fibrillar collagens and elastic fibre phenotype in floppy eyelid syndrome.
abstract: BACKGROUND
  The aims of this study are to investigate the expression of the main structural components of the tarsal extracellular matrix (ECM) in floppy eyelid syndrome (FES) focusing on elastic fibres and collagen types I and III, and also to identify possible cell-mediated inflammatory mechanisms in the pathogenesis of this condition.
  
  
  METHODS
  A histopathological case control study was conducted using 30 upper lid specimens from patients with FES and 15 undiseased upper lid control specimens. Structural ECM components were assessed using a combination of immunctorial ataining ohistochemical and techniques including antibodies to collagens I and III, Verhöeff's iron haematoxylin, Gomori's aldehyde fuchsin and Lillie's oxidised aldehyde fuchsin. The contribution of different cellular components of the inflammatory response was investigated by immunohistochemical techniques using antibodies to CD3, CD20, CD68. Slide scoring was performed using a semiquantitative technique on an ordinal scale. Statistical analysis was performed using matched ordinal regression analysis.
  
  
  RESULTS
  FES tarsal plate tissue demonstrated a decreased abundance of mature elastic fibres (P ≤ 0.001) and an increased abundance of oxytalan fibres (P = 0.006). Intensity of staining for collagens I (P = 0.012) and III (P < 0.001) was increased. No significant difference in the abundance of CD3, CD20 and CD68 expressing cells was identified.
  
  
  CONCLUSIONS
  The findings of altered elastic fibre phenotype and collagen accumulation are consistent with an adaptive response to cyclic mechanical loading of the tarsal plate, rather than an aetiological feature. These findings are important in understanding how the tarsal ECM responds to mechanical loading.
authors.affiliation: NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, UK. d.ezra@ucl.ac.uk
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Ezra
authors.forename: James S
authors.initials: JS
authors.lastname: Ellis
authors.forename: Christine
authors.initials: C
authors.lastname: Gaughan
authors.forename: Michèle
authors.initials: M
authors.lastname: Beaconsfield
authors.forename: Richard
authors.initials: R
authors.lastname: Collin
authors.forename: Catey
authors.initials: C
authors.lastname: Bunce
authors.forename: Maryse
authors.initials: M
authors.lastname: Bailly
authors.forename: Phil
authors.initials: P
authors.lastname: Luthert
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D016022:Case-Control Studies; D024042:Collagen Type I / Q000378:metabolism*; D024061:Collagen Type III / Q000378:metabolism*; D004547:Elastic Tissue / Q000378:metabolism* / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism; D005141:Eyelid Diseases / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D010641:Phenotype; D013577:Syndrome
chemical_list: D015703:Antigens, CD; D024042:Collagen Type I; D024061:Collagen Type III