← All decks
The first 25 slides, exactly as they appear. The full deck has 88 content slides.
Dermatology
The Biology of the Basement Membrane
Built from Dermatology, 5th Edition
What’s inside
8 sections · 88 slides
Overview
- What this chapter covers
Basement membrane overview
What a basement membrane is, and why the skin needs one
- What a basement membrane is
- Functions of a basement membrane
- Two basement membranes in skin
- Four ultrastructural subregions of the epidermal basement membrane
- The four subregions, top to bottom
- Laminated model of the epidermal basement membrane
- The laminated model, in plain terms
Origin of the epidermal basement membrane
Two different cell types build this one structure together
- Built by two different cell types
- What each cell type contributes
Basal keratinocyte hemidesmosome proteins
The anchor plaques and integrins that hold skin cells to the membrane
- Plectin holds the hemidesmosome together
- Plectin's role, confirmed in mice
- Bullous pemphigoid antigen 1: found through disease
- What happens when BPAG1 is missing
- Bullous pemphigoid antigen 2 (type XVII collagen)
- BPAG2 exists in two forms
- BPAG2 assembles into a triple helix
- BPAG2 and autoimmune or inherited disease
- What integrins are
- How integrins bind their targets
- Inside-out and outside-in signaling
- Kindlin-1 loss causes Kindler EB
- Kindlin-1 loss in mouse skin
- Integrin alpha6beta4: the hemidesmosome's integrin
- When alpha6 or beta4 integrin is missing
- Non-hemidesmosomal integrins in keratinocytes
- Losing alpha3 integrin disrupts the basement membrane
- CD151: the tetraspan organizer
- How hemidesmosomes assemble around CD151
- Molecular interactions within the epidermal basement membrane
The lamina densa
Laminins, type IV collagen, nidogen, and proteoglycans forming the membrane's dense core
- Laminins: a family of matrix proteins
- Naming laminin isoforms
- Structure of laminin 111
- The three main epidermal laminins
- Laminin 332's disease importance
- Comparing four laminin isoforms
- Laminin isoforms: identity
- Laminin isoforms: processing and assembly
- Laminin isoforms: tissue distribution
- Laminin isoforms: interactions and functions
- Type IV collagen: unique to basement membranes
- Where the different type IV collagen chains sit
- The 'hockey stick' shape of type IV collagen
- Diseases from defective type IV collagen
- Type IV collagen fragments with their own biology
- Nidogen and perlecan binding in the lamina densa
- Nidogen links the lamina densa together
- Nidogen-2 and what's missing without nidogen
- Heparan sulfate proteoglycans: the 'bottle brush' molecules
- Perlecan: 'spot welding' the network together
Anchoring fibrils and the sublamina densa region
Type VII collagen ties the lamina densa down to the dermis
- Type VII collagen: unique to stratified epithelium
- Why anchoring fibril assembly matters
- Assembly of anchoring fibrils
- COL7A1: a large but compact gene
- Dominant dystrophic EB: a different mechanism
- Epidermolysis bullosa acquisita: the autoimmune version
- Microfibrils in the papillary dermis
Basement membrane remodeling
A living barrier that is constantly rebuilt
- The basement membrane is not static
- Enzymes that remodel the membrane
The epidermal basement membrane in bullous diseases
When these proteins are attacked by antibodies or missing from birth
- Two roads to the same result: blistering
- Proteins targeted in both autoimmune and inherited blistering disease
- Autoantigens and mutated proteins mapped to the epidermal basement membrane
- Classifying subepidermal immunobullous disease
- Well-characterized subepidermal immunobullous diseases
- Salt-split skin: a diagnostic trick
- Indirect immunofluorescence on salt-split skin
- Indirect immunofluorescence localization on salt-split skin
- Direct immunofluorescence: testing the patient's own skin
- Direct immunofluorescence localization on salt-split skin
- Cleavage plane in salt-split skin
- Studying EB deepened our understanding of the membrane
- EB subtypes, by where the skin splits
- How pathologists confirm the cleavage plane
- Representative forms of epidermolysis bullosa
- Representative forms of epidermolysis bullosa (continued)
- Confirming the missing protein directly
- Adhesion proteins by region: a reference map
- Representative adhesion proteins in the epidermal basement membrane
- Key takeaways
- References
- References (continued)
- References (continued)
- References (continued)
- References (continued)
- References (continued)
- References (continued)
- References (continued)
- Dermatology, 5th Edition (2-Volume Set)