title: Novel approaches to characterize age-related remodelling of the dermal-epidermal junction in 2D, 3D and in vivo.
abstract: OBJECTIVE
  The dermal-epidermal junction (DEJ) forms epidermal protrusions down into the dermis (rete ridges) and dermal projections up into the epidermis (dermal papillae). Usually visualized in two-dimensions (2D), our knowledge of how the DEJ changes with ageing is limited. We aimed to characterize how this structure exists in 3D and changes with age.
  
  
  METHODS
  Photoprotected and photoexposed skin were imaged using reflectance confocal microscopy (RCM) in young and aged individuals. Biopsies of the imaged areas were processed for histological sectioning and for imaging using micro-computed X-ray tomography (microCT).
  
  
  RESULTS
  Images obtained from RCM and microCT were used to 3D reconstruct the DEJ. DEJ heights obtained from microCT images showed strong correlation with histology-measured heights. We proposed a novel definition of rete ridges (RRm) and dermal papillae (DPm), which allowed easier automated measurement of reduced DPmand RRmvolumes in aged skin from microCT reconstructions. An algorithm to map DPmconnectivity showed reduced lengths of DPmbranches with age.
  
  
  CONCLUSIONS
  Three-dimensional images illustrated the complex topography of the DEJ and highlighted the distinct morphology of dermal papillae compared with rete ridges, which is not evident when evaluating 2D sections. Ex vivo imaging was more successful in differentiating DEJ architecture with respect to age.
authors: Centre for Dermatology Research, Institute of Inflammation & Repair, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.|The Dermatology Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors: V L
authors: VL
authors: Newton
authors: School of Materials, The University of Manchester, Manchester, UK.
authors: R S
authors: RS
authors: Bradley
authors: Newtone Technologies, Lyon, France.
authors: P
authors: P
authors: Seroul
authors: Newtone Technologies, Lyon, France.
authors: M
authors: M
authors: Cherel
authors: Centre for Dermatology Research, Institute of Inflammation & Repair, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.|The Dermatology Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors: C E M
authors: CE
authors: Griffiths
authors: AVR Consulting Ltd, Northwich, UK.
authors: A V
authors: AV
authors: Rawlings
authors: DSM Nutritional Products Ltd, Kaiseraugst, Switzerland.
authors: R
authors: R
authors: Voegeli
authors: Centre for Dermatology Research, Institute of Inflammation & Repair, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK.|The Dermatology Centre, Salford Royal NHS Foundation Trust, Salford, UK.
authors: R E B
authors: RE
authors: Watson
authors: Centre for Tissue Injury and Repair, Institute of Inflammation & Repair, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK.
authors: M J
authors: MJ
authors: Sherratt
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000473:pathology*; D020405:Dermis / Q000166:cytology* / Q000000981:diagnostic imaging / Q000502:physiology; D000078404:Epidermal Cells; D004817:Epidermis / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D018613:Microscopy, Confocal / Q000379:methods; D015595:Skin Aging / Q000473:pathology*; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult
keywords: X-ray computed tomography; dermal papilla; dermal-epidermal junction; photodamage; reflectance confocal microscopy; rete ridge; skin ageing