Scott Walsh MD PhD FRCPC Sunnybrook Health Sciences Centre

Presentation on theme: "Scott Walsh MD PhD FRCPC Sunnybrook Health Sciences Centre"— Presentation transcript:

1 The ILC Foundation: Ehlers Danlos Complex Dermatologic Features and Issues
Scott Walsh MD PhD FRCPC Sunnybrook Health Sciences Centre University of Toronto Peter Gilgan Centre November 2 and 3, 2019

2 Disclosures: No conflicts with Industry relevant to this talk.

3 Ehlers Danlos Syndromes:
Cardinal features of EDS: Hyper-extensibility of the skin. Hypermobility of the joints. Tissue fragility (skin, blood vessels). Many different types of EDS.

4 Ehlers Danlos Syndromes:
Type of EDS Former System Gene Inheritance Features Classic I and II Collagen V (alpha I and II) AD Atypical scarring and hypermobility Hypermobile III ? Hypermobility and pain Vascular IV Collagen III (rare collagen I) Arterial rupture and small joint hypermobility Kyphoscoliosis VI Lysyl hydroxylase (PLOD1) AR Kyphoscoliosis, hypotonia and scarring, globe rupture. Arthrochalasia VIIa, VIIb Collagen I (alpha I and II) Congenital hip dislocation, hypotonia, scarring, severe hypermobility. Dermatosparaxis VIIc Procollagen N peptidase (ADAMTS2) Extreme skin fragility, progressive joint hypermobility, redundant skin. Adapted from Beighton et al Am. J. Med. Genet. 77: 31-7.

5 Ehlers Danlos Syndromes:
Byers and Murray, 2012.

6 Malfait et al. 2017. Am. J. Med. Genet
Malfait et al Am. J. Med. Genet. Part C Semin Med Genet 175C: 8-26.

7 Malfait et al. 2017. Am. J. Med. Genet
Malfait et al Am. J. Med. Genet. Part C Semin Med Genet 175C: 8-26.

8 Malfait et al. 2017. Am. J. Med. Genet
Malfait et al Am. J. Med. Genet. Part C Semin Med Genet 175C: 8-26.

9 Malfait et al. 2017. Am. J. Med. Genet
Malfait et al Am. J. Med. Genet. Part C Semin Med Genet 175C: 8-26.

10 Ehlers Danlos Syndromes:
Genes affected: Fibrillar collagens. Enzymes that process fibrillar collagens. Proteins that interact with collagens. Mechanisms: Haplo-insufficiency. Dominant negative effect (abnormal structure). Abnormal solubility and strength.

11 Outline: Review structure of skin with respect to EDS and the interplay of different molecules: Collagen Elastin Ground Substance The role of Electron microscopy in inherited disorders of connective tissue. Hypermobility Spectrum Disorder and changes that can occur with an altered matrix. Effects on activity of other cell types Effects on migration of other cells

12 Ehlers Danlos Syndromes
Skin: Collagen Strength of skin Elastin Resiliency of skin Ground Substance (proteoglycans and glycosaminoglycans) Turgor or texture of skin Abnormality in any one component can affect the proper assembly of the other components.

13 Ehlers Danlos Syndromes:
Disorders primarily of disturbed collagen fibrillogenesis. The morphology and strength of collagen is compromised.

14 Ehlers Danlos Syndromes
Collagen is the major protein in skin, ligament, tendon, bone. 29 different types of collagen (43 genes). Triple helix with interactive amino acids on the outside and compact amino acids on the inside. Homotrimers (proteins from same gene) Heterotrimers (proteins from different genes)

15 Ehlers Danlos Syndromes
"velvety texture" "doughy texture" "thin skin" "hyperextensible" Volar forearm - snap back.

16 Collagen: Most abundant protein in the body.
70% of dry weight of dermis. Collagen Definition: Right handed triple-helical domain consisting of 3 left-handed polypeptide chains with a Gly-X-Y sequence where X is often proline and Y is often hydroxyproline Structural component of the extracellular matrix. Collagens can be homotrimers or heterotrimers.

17 Collagen - Classification
Two broad classes: Fibrillar collagens form cross-striated fibrils with 67 nm periodicity. Non-fibrillar collagens do not form cross-striated fibrils as usually have non-collagenous portions that give molecule flexibility (arms for molecules to bind to). Several of these different types of collagens interact to make a large collagen fibre.

18 Fang et al. 2012

19 Collagen V Fang et al. 2012

20 Collagen V Collagen I Fang et al. 2012

21 Collagen III Collagen V Collagen I Fang et al. 2012

22 Fang et al. 2012 Collagen III FACIT Collagens XII and XIV Collagen V

23 Fibrillar Collagen - V 5% of dermal collagen.
Located at core of collagen fibrils in the skin.

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28 Castori ISBN Dermatol

29 Morais et al. 2013. Acta Dermatovenerol. Croat. 21: 118-22.

30 EDS-I/II – Classical type
AD Clinical: Thinned/atrophic scars Papyraceus, cigarette paper, fish mouth. Molluscoid pseudotumours, spherules. Hyperextensible skin Joint laxity/hypermobility Small and large joint. COL5A1 or COL5A2 mutations. Morais et al Acta. Dermatovenerol. Croat. 21: ; Malfait et al Genet. Med. 12: ; Malfait et al Hum. Mutat. 25:

31 Fibrillar Collagen - III
Embryonic/fetal life. 10% of collagen in adult dermis. Enriched in blood vessels, viscera (GI). Homotrimer; larger than collagen I. Forms a scaffold on which organs are built.

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33 EDS-IV – Vascular/ecchymotic
AD with 2 clinical presentations: Acrogeric variety Mutations in triple helix or carboxy-end. Characteristic facies Non-acrogeric Mutations in amino terminus or single null allele. Clinical: Thin, translucent skin Arterial rupture/dissection/aneurysm/bowel perforation/uterine rupture Extensive bruising +/- acrogeria hypermobility of small joints Varicosities family history of sudden death. Rx: ?aortic root graft; avoid NSAIDs, contact sports. 25% one event by 20 years; 80% one event by 40 years. Oderich et al J. Vasc. Surg. 42: ; Germain and Herrera-Guzman, Ann. Genetic. 47: 1-9; Germain Ann. Vasc. Surg. 16: 391-7

34 Fibrillar Collagen I Most abundant collagen.
80% of collagen in dermis; bone. Heterotrimer of [ά1(I)]2ά2(I). Best studied and model for fibrillar collagen biosynthesis.

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36 Osteogenesis imperfecta

37 Fibrillar Collagen I Condition Arthrochalasia EDS (Col 1A1 or 1A2)
Cardiac valvular EDS (1A2) Classical EDS (1A1) - rare variants Vascular EDS (1A1) - rare variant Osteogenesis imperfecta - helical mutations (1A1 and 1A2) Caffey disease (1A1) OI/EDS overlap (1A2) Lu et al Intractable and Rare Diseases Research. 8(2):

38 Collagen Biosynthesis/Fibrillogenesis:
Model Collagen I Collagen III (fetal) Collagen V (regulatory) Many forms of EDS occur when there is a problem in formation of fibrillar collagen.

39 Biosynthesis of Fibrillar Collagen I
Formed as a procollagen that becomes an insoluble mature collagen with processing. Transcription: Upregulated by retinoic acid, TGF-B, insulin, ascorbic acid. Down-regulated by glucocorticoids, FGF, TNF.

40 Biosynthesis of Fibrillar Collagen I
Endoplasmic Reticulum: Translation of mRNA into ER. Emerging polypeptide is bound by: HSP47 prevents aggregation in ER. Prolyl-4-hydrolase and protein disulfide isomerase. Peptidyl prolyl cis-trans isomerase. Post-translational enzymatic modifications occur while translation is being completed.

41 Dordoni et al. 2016. Am. J. Med. Genet. 170A: 2031-8.

42 FKBP14-Related Ehlers Danlos Syndrome
Dordoni et al Am. J. Med. Genet. 170A:

43 FKBP14-Related EDS: AR Peptidyl-prolyl cis-trans isomerases. Features:
Kyphoscoliosis Myopathy Joint hypermobility Congenital hearing loss Atypical scarring and skin redundancy. Dordoni et al Am. J. Med. Genet. 170A:

44 Biosynthesis of Fibrillar Collagen I
5 Enzymes in ER: Proly-4-hydrolase Converts proline in Y of Gly-X-Y to hydroxyproline. Cofactors Fe+2, O2, ascorbic acid, ά-ketoglutarate. Prolyl-3-hydrolase Converts proline in X of Gly-X-Y to HYP when Y is already HYP. Lysyl hydrolase Hydroxylates lysine residues in Y of Gly-X-Y. Important for future glycosylation and cross-linking. Galatosyl-transferase Transfers UDP-galactose to hydroxylysine. Collagen glycosyl-transferase Transfers UDP-glucose to galactosyl hydroxylysine.

45 Overmans et al. 2010

46 Ehlers Danlos Kyphoscoliotic type
Overmans et al. 2010

47 EDS – Kyphoscoliotic (VIA)
AR Deficiency of lysyl hydrolase type I (PLOD). Unable to hydroxylate lysines and hence can’t later cross-link them for collagen stability and insolubility. Clinical: Kyphoscoliosis at birth Scleral fragility with globe rupture/retinal detachment Severe muscular hypotonia at birth Generalized joint laxity +/- large artery rupture, atrophic scars, tissue fragility, marfanoid habitus, easy bruising, microcornea, osteopenia/osteoporosis Tosun et al Pediatr. Neurol. 51:566-9; Overmans et al Am. J. Med. Genet. 149A:

48 Biosynthesis of Fibrillar Collagen I
Modified triple helix zippered up in ER. Secretion of Procollagen Aggregate laterally in golgi (loss of HSP47) Secreted via golgi vacuoles along microtubules. Secreted into crypts around cell (fibripositors).

49 Biosynthesis of Fibrillar Collagen I
Extracellular Processing: Procollagen N-proteinase ADAMTS2; N-propeptide downregulates collagen. Procollagen C-proteinase BMP 1. Lysyl oxidase Deaminates lysyl and hydroxylysyl residues (Cu). Allysyne or hydroxyallysine crosslinks. Now strong and insoluble collagen.

50 Malfait et al. 2004

51 Dermatosparaxis Malfait et al. 2004

52 EDS- Dermatosparaxis type (VIIC)
AR – due to deficiency of procollagen I N-proteinase. Clinical: Severe skin fragility with avulsions Sagging, redundant skin (cutis laxa) +/- easy bruising, blue sclerae, PROM, joint laxity, umbilical hernias Van Damme et al Genet. Med. 18: ; Malfait et al Am. J. Med. Genet. 131A:

53 Hatamochi et al. 2014

54 Arthrochalasia (VIIA/B)
Hatamochi et al. 2014

55 EDS-Arthrochalasia type (VIIA/B)
AD – missing exon 6 (N-propeptide cleavage site) in either COL1ά(I) or COL1ά(II) genes. Clinical: Bilateral congenital hip dislocations Generalized and severe joint laxity +/- skin hyperextensibility, tissue fragility, atrophic scars, easy bruising, muscular hypotonia, wormian bones. N-propeptide remains associated and increases solubility of collagen and ↓feedback ↑collagen. Hatamochi et al Gene 538: ; Klaassens et al Clin. Genet. 82:

56 Koide and Nagata, 2005.

57 Koide and Nagata, 2005.

58 Koide and Nagata, 2005.

59 Koide and Nagata, 2005.

60 Koide and Nagata, 2005.

61 Koide and Nagata, 2005.

62 Koide and Nagata, 2005.

63 Collagen Biosynthesis
Type V Collagen regulates fibrillogenesis. Type 5 at nucleus of fibre with binding sites pointing outwards, surrounded by types I and III with FACIT collagens XII and XIV to link to outside. Link to ground substance proteins, cell surface receptors and elastin.

64 The Dermis Collagen - gives strength Elastin - gives resilience
Ground substance - gives texture.

65 Elastin: Continuous network from the epidermal junction to the hypodermis. Gives skin its resilience. Graduated amounts of mature elastin deposited on microfibrillar proteins. May have some effect on collagen regulation. Defects: Marfan's Syndrome, cutis laxa, etc.

66 Ground Substance Amorphous material of the extra-cellular and extra-fibrillar matrix. Binds water and maintains hydration of the dermis (texture). Composed of polysaccharides with negative charges. Glycosaminoglycans Proteoglycans (protein core with glycosaminoglycan) Proteins Many associate with collagens and can regulate the diameter of collagen fibrils.

67 Schaefer and Schaefer, 2010

68 Castori C. et al. 2019. Am. J. Med. Genet. 179A: 317-21

69 Musculocontractural EDS
Enzyme carbohydrate sulfotransferase 14 (CHST14) not working properly and one of the proteoglycan decorin doesn't get its proper glycanation and hence doesn't bind collagen properly. Myopathy with muscle contractures. Skin hyperextensibility Skin fragility Spinal deformities.

70 Musculocontractural EDS
-linear bridges of proteoglycans rather than curved bridges. -failure to regulate collagen fibre diameter and spacing. Hirose T et al BBA

71 Musculocontractural EDS
-linear bridges of proteoglycans rather than curved bridges. -failure to regulate collagen fibre diameter and spacing. Hirose T et al BBA

72 Musculocontractural EDS
-linear bridges of proteoglycans rather than curved bridges. -failure to regulate collagen fibre diameter and spacing. Hirose T et al BBA

73 Syx D. et al. 2019. Human Mol. Gen. 28(11): 1853-64.

74 AEBP1-Related Classical-Like EDS:
New AR variant recently described. Aortic carboxypeptidase-like protein in the ground substance that appears to be important in binding collagen fibres in skin, blood vessels, lung and bone (periosteum). Hyperextensible skin Joint hypermobility Atrophic scars Thin and translucent skin Osteoporosis Ritelli M. et al. Genes. 10 (135): 1-14; Syx D. et al Human Mol. Gen. 28(11):

75 AEBP1-Related Classical-Like EDS:
Syx D. et al Human Mol. Gen. 28(11):

76 AEBP1-Related Classical-Like EDS:
Syx D. et al Human Mol. Gen. 28(11):

77 Ehlers Danlos Syndromes:
Genes affected: Fibrillar and non-fibrillar collagens. Enzymes that process fibrillar collagens. Glycosaminoglycan synthesis (interacts with collagen to regulate diameter). Matrix proteins that influence collagen diameter.

78 Role of Electron Microscopy:
Normally collagen synthesis is tightly controlled with identical size and spacing of molecules. Inherited disorders of connective tissue (IDCT) demonstrate variation in collagen size and interfibrillar spacing when assessed by TEM. Can be used to support the presence of an IDCT.

79 Ehlers Danlos Syndromes:
Skin biopsy taken from upper inner arm or lower back/upper buttock (sun protected site). Glutaraldehyde and fixed for TEM. Magnification up to X. Can assess variations in collagen fibrils.

80 Mao and Bristow, 2001. J. Clin. Invest. 107: 1063-9.

81 Classic EDS Hausser and Anton-Lamprecht, Hum. Genet. 3:

82 Hausser and Anton-Lamprecht, 1994. Hum. Genet. 3: 394-407.

83 Vascular type EDS Sobey, Arch. Dis. Child. 100:

84 Dermatosparaxis Van Damme et al Genet. Med. 18: ; Malfait et al Am. J. Med. Genet. 131A:

85 Hypermobile type EDS Hermanns-Le and Pierard, Am. J. Dermatopathol. 29:

86 Hypermobile type EDS Hermanns-Le et al J. Biomed. Biotech ; Hermanns-Le and Pierard, Am. J. Dermatopathol. 29:

87 Electron Microscopy and Collagen:
EDS variants. Other inherited disorders of connective tissue: Osteogenesis imperfecta Caffey Disease Marfan's Syndrome Loeys-Dietz Pseudoxanthoma elasticum Cutis laxa Menkes Acquired disorders: Scleredema, scleromyxedema, nephrogenic fibrosing dermopathy.

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91 Hypermobility Spectrum Disorder:
Likely many disorders with common presentation. AD. Previously EDS Hypermobile type (subtype now only classified as EDS Hypermobile type). Features: Generalized joint hypermobility. Chronic joint and muscular pain. Recurrent joint dislocations or subluxations. Symptoms of autonomic dysfunction (dysautonomia). Easy bruising. No widened/papyraceous scars. Functional gastrointestinal disorders. Small fibre neuropathy Mast cell disorders Behaves like an inflammatory disorder in many patients. Martin A Eur. J. Med. Genet. In press; Forghani I Balkan Med. J. 36: 12-6; Caston M. and Hakim A Curr. Opin. Pediatr. 29(6):

92 Hypermobile type EDS: No single gene to date:
Proteoglycans that regulate collagens. FACIT collagens. Elastin-related proteins.

93 Molecular Basis of HSD? Both HSD and hEDS fibroblasts in contrast to controls show the exact same: Upregulation of specific wound receptors Upregulation or inflammatory mediators Disarray of extracellular matrix Prevalence of myofibroblast transition from fibroblasts (seen in chronic wound responses) not seen in other types of EDS. Zoppi N. et al BBA

94 Molecular Basis of HSD Other Roles of Normal Matrix:
Migration and maturation of other matrical components (nerves, blood vessels, muscle, etc.) Stabilization and activation of other cell types. Mast cells are intimate matrix cells in skin and gastrointestinal tract. Is there an abnormal effect from the matrix? Nerves are intimate with the matrix and could these be affected by the upregulated wound signals?

95 EDS Management from Dermatologic Perspective:

96 EDS - Management: Supplemental Vitamin C. Supplemental Vitamin A.
Avoid glucocorticoids where possible. Protection from Trauma. Avoid contact sports. Avoid ASA. Vasopressin or transexaminic acid. Sobey, Arch. Dis. Child. 100: 57-61; Morais et al Acta Dermatovenerol. Croat. 21: ; Malfait et al Genet. Med. 12: ; Mantle et al Med. Hypoth. 64:

97 EDS - Management: Suturing wounds Double layer closures.
Stitches held twice as long. Additional tape bandaging over wounds. Mast cell stabilization Cromolyn, ketotifen, monteleukast, omalizumab Antihistamines Sobey, Arch. Dis. Child. 100: 57-61; Morais et al Acta Dermatovenerol. Croat. 21: ; Mantle et al Med. Hypoth. 64: ;

98 Summary: The skin matrix is a well-controlled interplay between:
Collagen Elastin Ground Substance Electron microscopy can detect abnormalities in matrical structure and support a diagnosis of an inherited disorders of connective tissue. Hypermobility Spectrum Disorder has changes in the matrix that likely can exert effect on both the migration and subsequent activity of other cell types.