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Uitto J, Atanasova VS, Jiang Q, South AP. Precision Medicine for Heritable Skin Diseases-The Paradigm of Epidermolysis Bullosa. J Investig Dermatol Symp Proc 2018; 19:S74-S76. [PMID: 30471755 DOI: 10.1016/j.jisp.2018.09.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The 2016 JID Beijing Workshop, held in the context of the 5th National Congress of Investigative Dermatology of the Chinese Society of Dermatology, had the thematic focus on "Precision Medicine in Dermatology." This theme was extremely timely, yet forward-looking, due to the fact that precision medicine is one of the fastest growing paradigms of contemporary medicine (Box 1).
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
| | - Velina S Atanasova
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Qiujie Jiang
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Andrew P South
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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2
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Uitto J, Has C, Vahidnezhad H, Youssefian L, Bruckner-Tuderman L. Molecular pathology of the basement membrane zone in heritable blistering diseases:: The paradigm of epidermolysis bullosa. Matrix Biol 2016; 57-58:76-85. [PMID: 27496350 DOI: 10.1016/j.matbio.2016.07.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/19/2016] [Accepted: 07/28/2016] [Indexed: 01/03/2023]
Abstract
Epidermolysis bullosa (EB), a phenotypically heterogeneous group of skin fragility disorders, is characterized by blistering and erosions with considerable morbidity and mortality. Mutations in as many as 18 distinct genes expressed at the cutaneous basement membrane zone have been shown to be associated with the blistering phenotype, attesting to the role of the corresponding proteins in providing stable association of the epidermis to the dermis through adhesion at the dermo-epidermal basement membrane zone. Thus, different forms of EB have been highly instructive in providing information on the physiological functions of these proteins as integral components of the supramolecular adhesion complexes. In addition, precise information of the underlying genes and distinct mutations in families with EB has been helpful in subclassification of the disease with prognostic implications, as well as for prenatal testing and preimplantation genetic diagnosis. Furthermore, knowledge of the types of mutations is a prerequisite for application of allele-specific treatment approaches that have been recently developed, including read-through of premature termination codon mutations and chaperone-facilitated intracellular transport of conformationally altered proteins to proper physiologic subcellular location. Collectively, EB serves as a paradigm of heritable skin diseases in which significant progress has been made in identifying the underlying genetic bases and associated aberrant pathways leading from mutations to the phenotype, thus allowing application of precision medicine for this, currently intractable group of diseases.
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, The Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA.
| | - Cristina Has
- Department of Dermatology, University of Freiburg, Freiburg, Germany
| | - Hassan Vahidnezhad
- Department of Dermatology and Cutaneous Biology, The Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA; Biotechnology Research Center, Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran
| | - Leila Youssefian
- Department of Dermatology and Cutaneous Biology, The Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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3
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Vahidnezhad H, Youssefian L, Saeidian AH, Mozafari N, Barzegar M, Sotoudeh S, Daneshpazhooh M, Isaian A, Zeinali S, Uitto J. KRT5 and KRT14 Mutations in Epidermolysis Bullosa Simplex with Phenotypic Heterogeneity, and Evidence of Semidominant Inheritance in a Multiplex Family. J Invest Dermatol 2016; 136:1897-1901. [PMID: 27283507 DOI: 10.1016/j.jid.2016.05.106] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/03/2016] [Accepted: 05/17/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Hassan Vahidnezhad
- Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran; Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Leila Youssefian
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Amir Hossein Saeidian
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Nikoo Mozafari
- Skin Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Soheila Sotoudeh
- Department of Dermatology, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Daneshpazhooh
- Autoimmune Bullous Diseases Research Center, Department of Dermatology, Tehran University of Medical Sciences, Tehran, Iran
| | - Anna Isaian
- Pediatrics Center of Excellence Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sirous Zeinali
- Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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South AP, Li Q, Uitto J. Next-generation sequencing for mutation detection in heritable skin diseases: the paradigm of pseudoxanthoma elasticum. J Invest Dermatol 2015; 135:937-940. [PMID: 25785945 DOI: 10.1038/jid.2014.521] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Next-generation sequencing applied either to the entire genome or to a subset, such as a whole exome, has revolutionized the search for pathogenic mutations in heritable diseases, including genodermatoses. In this issue, Hosen et al. applied whole-exome sequencing to identify potential pathogenic mutations in four candidate genes associated with pseudoxanthoma elasticum, the prototype of ectopic mineralization disorders. The study highlights the advantages of this approach over traditional Sanger sequencing, including expedience and cost, but it also illustrates some of the challenges encountered in implementing this rapidly evolving technology.
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Affiliation(s)
- Andrew P South
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Qiaoli Li
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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Uitto J, Has C, Bruckner-Tuderman L. Cell-based therapies for epidermolysis bullosa - from bench to bedside. J Dtsch Dermatol Ges 2013; 10:803-7. [PMID: 23107326 DOI: 10.1111/j.1610-0387.2012.08035.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Significant progress has been made over the past two decades in molecular genetics of epidermolysis bullosa (EB), a group of heritable blistering disorders, with diagnostic and prognostic implications. More recently, novel molecular approaches have been developed towards potential treatment of EB, with emphasis on gene-, protein-, and cell-based strategies. This overview highlights cell-based approaches that have recently been tested in pilot clinical trials, attesting to the potential of regenerative medicine for blistering skin diseases.
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Philadelphia, Pennsylvania 19107, USA.
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Cavazza A, Cocchiarella F, Bartholomae C, Schmidt M, Pincelli C, Larcher F, Mavilio F. Self-inactivating MLV vectors have a reduced genotoxic profile in human epidermal keratinocytes. Gene Ther 2013; 20:949-57. [PMID: 23615186 DOI: 10.1038/gt.2013.18] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 03/18/2013] [Accepted: 03/25/2013] [Indexed: 02/07/2023]
Abstract
Transplantation of epithelia derived from keratinocyte stem cells transduced by retroviral vectors is a potential therapy for epidermolysis bullosa (EB), a family of inherited skin adhesion defects. The biosafety characteristics of retroviral vectors in keratinocytes are, however, poorly defined. We developed self-inactivating (SIN) vectors derived from the Moloney murine leukemia (MLV) and the human immunodeficiency (HIV) viruses expressing therapeutic levels of LAMB3, a transgene defective in junctional EB, and tested their integration profile in human primary keratinocytes. The SIN-HIV vector showed the expected preference for transcribed genes while the SIN-MLV vector integrated preferentially in regulatory elements, but showed a significantly lower tendency to target cell growth-related genes, transcription start sites and epigenetically defined promoters compared with a wild-type MLV vector in an epithelial cell context. A quantitative gene expression assay in individual keratinocyte clones showed that MLV-derived vectors deregulate expression of targeted genes at a lower frequency than in hematopoietic cells, and that the SIN-MLV design has the lowest activity compared to both MLV and SIN-HIV vectors. This study indicates that SIN-MLV vectors may have a better safety profile in keratinocyte than in hematopoietic cells, and be a reasonable alternative to lentiviral vectors for gene therapy of inherited skin disorders.
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Affiliation(s)
- A Cavazza
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
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Avci P, Sadasivam M, Gupta A, De Melo WC, Huang YY, Yin R, Chandran R, Kumar R, Otufowora A, Nyame T, Hamblin MR. Animal models of skin disease for drug discovery. Expert Opin Drug Discov 2013; 8:331-55. [PMID: 23293893 DOI: 10.1517/17460441.2013.761202] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
INTRODUCTION Discovery of novel drugs, treatments, and testing of consumer products in the field of dermatology is a multi-billion dollar business. Due to the distressing nature of many dermatological diseases, and the enormous consumer demand for products to reverse the effects of skin photodamage, aging, and hair loss, this is a very active field. AREAS COVERED In this paper, we will cover the use of animal models that have been reported to recapitulate to a greater or lesser extent the features of human dermatological disease. There has been a remarkable increase in the number and variety of transgenic mouse models in recent years, and the basic strategy for constructing them is outlined. EXPERT OPINION Inflammatory and autoimmune skin diseases are all represented by a range of mouse models both transgenic and normal. Skin cancer is mainly studied in mice and fish. Wound healing is studied in a wider range of animal species, and skin infections such as acne and leprosy also have been studied in animal models. Moving to the more consumer-oriented area of dermatology, there are models for studying the harmful effect of sunlight on the skin, and testing of sunscreens, and several different animal models of hair loss or alopecia.
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Affiliation(s)
- Pinar Avci
- Harvard Medical School, Massachusetts General Hospital, Wellman Center for Photomedicine, Department of Dermatology, Boston MA, USA
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Uitto J. Rare heritable skin diseases: targets for regenerative medicine. J Invest Dermatol 2012; 132:2485-8. [PMID: 23069901 DOI: 10.1038/jid.2012.334] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Kopecki Z, Ruzehaji N, Turner C, Iwata H, Ludwig RJ, Zillikens D, Murrell DF, Cowin AJ. Topically applied flightless I neutralizing antibodies improve healing of blistered skin in a murine model of epidermolysis bullosa acquisita. J Invest Dermatol 2012; 133:1008-16. [PMID: 23223144 DOI: 10.1038/jid.2012.457] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Epidermolysis bullosa (EB) is a chronic inheritable disease that leads to severe blistering and fibrosis. Previous studies have shown that the actin cytoskeletal protein flightless I (Flii) impairs wound healing associated with EB. Using a mouse model of EB acquisita (EBA), the effect of "mopping up" Flii using Flii-neutralizing antibodies (FnAbs) before, during, and after blister formation was determined. FnAbs, incorporated into a cream vehicle and applied topically to the skin, penetrated into the basal epidermis and upper papillary dermis but were not detected in serum or other organs and did not alter neutrophil or macrophage infiltration into the blistered skin. Histological assessment of blister severity showed that treatment of early-stage blisters with FnAb cream reduced their severity and improved their rate of healing. Treatment of established blisters with FnAb cream also improved healing and restored the skin's tensile strength toward that of normal skin. Repeated application of FnAbs to EBA skin before the onset of blistering reduced the severity of skin blistering. Independent of when the FnAbs were applied, skin barrier function and wound healing were improved and skin fragility was reduced, suggesting that FnAbs could potentially improve healing of patients with EB.
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Affiliation(s)
- Zlatko Kopecki
- Women's and Children's Health Research Institute, North Adelaide, South Australia, Australia.
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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Kopecki Z, Arkell RM, Strudwick XL, Hirose M, Ludwig RJ, Kern JS, Bruckner-Tuderman L, Zillikens D, Murrell DF, Cowin AJ. Overexpression of the Flii
gene increases dermal-epidermal blistering in an autoimmune ColVII mouse model of epidermolysis bullosa acquisita. J Pathol 2011; 225:401-13. [PMID: 21984127 DOI: 10.1002/path.2973] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 07/18/2011] [Indexed: 11/06/2022]
Affiliation(s)
- Zlatko Kopecki
- Women's and Children's Health Research Institute, 72 King William Road, North Adelaide, SA, Australia
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Abstract
The development of multicellular organisms, as well as maintenance of organ architecture and function, requires robust regulation of cell fates. This is in part achieved by conserved signaling pathways through which cells process extracellular information and translate this information into changes in proliferation, differentiation, migration, and cell shape. Gene deletion studies in higher eukaryotes have assigned critical roles for components of the extracellular matrix (ECM) and their cellular receptors in a vast number of developmental processes, indicating that a large proportion of this signaling is regulated by cell-ECM interactions. In addition, genetic alterations in components of this signaling axis play causative roles in several human diseases. This review will discuss what genetic analyses in mice and lower organisms have taught us about adhesion signaling in development and disease.
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Affiliation(s)
- Sara A Wickström
- Paul Gerson Una Group, Skin Homeostasis and Ageing, Max Planck Institute for Biology of Ageing, 50937 Cologne, Germany.
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Abstract
Heritable skin diseases represent a broad spectrum of clinical manifestations due to mutations in ∼500 different genes. A number of model systems have been developed to advance our understanding of the pathomechanisms of genodermatoses. Zebrafish (Danio rerio), a freshwater vertebrate, has a well-characterized genome, the expression of which can be easily manipulated. The larvae develop rapidly, with all major organs having developed by 5-6 days post-fertilization, including the skin, consisting of the epidermis comprising two cell layers and separated from the dermal collagenous matrix by a basement membrane. This perspective highlights the morphological and ultrastructural features of zebrafish skin, in the context of cutaneous gene expression. These observations suggest that zebrafish provide a useful model system to study the molecular aspects of skin development, as well as the pathogenesis and treatment of select heritable skin diseases.
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Differentiation of mouse induced pluripotent stem cells into a multipotent keratinocyte lineage. J Invest Dermatol 2010; 131:857-64. [PMID: 21150926 DOI: 10.1038/jid.2010.364] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent breakthroughs in the generation of induced pluripotent stem cells (iPSCs) have provided a novel renewable source of cells with embryonic stem cell-like properties, which may potentially be used for gene therapy and tissue engineering. Although iPSCs have been differentiated into various cell types, iPSC-derived keratinocytes have not yet been obtained. In this study, we report the in vitro differentiation of mouse iPSCs into a keratinocyte lineage through sequential applications of retinoic acid and bone-morphogenetic protein-4 and growth on collagen IV-coated plates. We show that iPSCs can be differentiated into functional keratinocytes capable of regenerating a fully differentiated epidermis, hair follicles, and sebaceous glands in an in vivo environment. Keratinocytes derived from iPSCs displayed characteristics similar to those of primary keratinocytes with respect to gene and protein expression, as well as their ability to differentiate in vitro and to reconstitute normal skin and its appendages in an in vivo assay. At present, no effective therapeutic treatments are available for many genetic skin diseases. The development of methods for the efficient differentiation of iPSCs into a keratinocyte lineage will enable us to determine whether genetically corrected autologous iPSCs can be used to generate a permanent corrective therapy for these diseases.
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Abstract
Integrins bind extracellular matrix fibrils and associate with intracellular actin filaments through a variety of cytoskeletal linker proteins to mechanically connect intracellular and extracellular structures. Each component of the linkage from the cytoskeleton through the integrin-mediated adhesions to the extracellular matrix therefore transmits forces that may derive from both intracellular, myosin-generated contractile forces and forces from outside the cell. These forces activate a wide range of signaling pathways and genetic programs to control cell survival, fate, and behavior. Additionally, cells sense the physical properties of their surrounding environment through forces exerted on integrin-mediated adhesions. This article first summarizes current knowledge about regulation of cell function by mechanical forces acting through integrin-mediated adhesions and then discusses models for mechanotransduction and sensing of environmental forces.
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Affiliation(s)
- Martin Alexander Schwartz
- Departments of Microbiology, Cell Biology, and Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22908, USA.
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Bruckner-Tuderman L, McGrath JA, Robinson EC, Uitto J. Animal models of epidermolysis bullosa: update 2010. J Invest Dermatol 2010; 130:1485-8. [PMID: 20463671 DOI: 10.1038/jid.2010.75] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Uitto J, McGrath JA, Rodeck U, Bruckner-Tuderman L, Robinson EC. Progress in epidermolysis bullosa research: toward treatment and cure. J Invest Dermatol 2010; 130:1778-84. [PMID: 20393479 DOI: 10.1038/jid.2010.90] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Epidermolysis bullosa (EB) is a clinically and genetically heterogeneous group of blistering disorders with considerable morbidity and mortality. Two decades ago, EB entered the molecular era with the identification of mutations in specific genes expressed within the cutaneous basement membrane zone; mutations in 14 genes have now been identified. This progress has now formed the basis for development of novel molecular therapies for this disease.
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
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Nagy N, McGrath JA. Blistering skin diseases: a bridge between dermatopathology and molecular biology. Histopathology 2010; 56:91-9. [PMID: 20055907 DOI: 10.1111/j.1365-2559.2009.03442.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although dermatopathology and molecular biology are often considered to be separate laboratory disciplines, the respective approaches are far from mutually exclusive. This is certainly the case for understanding the pathology of blistering skin diseases, both acquired and inherited. For example, in toxic epidermal necrolysis, dermatopathology in isolation may provide few clues to disease pathogenesis. There is widespread keratinocyte apoptosis and a variable infiltrate of cytotoxic T cells, but morphology alone offers little insight into what causes the epidermal destruction. In contrast, molecular biology studies have revealed several key processes that help explain the keratinocyte death, including increased expression of death receptors and their ligands on keratinocyte cell membranes as well as the presence of local or systemic immunocyte-derived cytolytic granules. For some inherited blistering diseases, however, such as epidermolysis bullosa, the molecular pathology is complex and difficult to unravel in isolation, yet the addition of dermatopathology is helpful in focusing molecular investigations. Notably, immunolabelling of cell adhesion proteins using specific antibody probes can identify reduced or absent immunoreactivity for candidate genes/proteins. Bridging dermatopathology and molecular biology investigations facilitates a greater understanding of disease processes, improves diagnostic accuracy, and provides a basis for the development and appraisal of new treatments.
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Affiliation(s)
- Nikoletta Nagy
- St John's Institute of Dermatology, King's College London, Guy's Campus, London, UK
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Abstract
Pseudoxanthoma elasticum (PXE), a prototypic heritable disorder with ectopic mineralization, manifests with characteristic skin findings, ocular involvement and cardiovascular problems, with considerable morbidity and mortality. The classic forms of PXE are due to loss-of-function mutations in the ABCC6 gene, which encodes ABCC6, a transmembrane efflux transporter expressed primarily in the liver. Several lines of evidence suggest that PXE is a primary metabolic disorder, which in the absence of ABCC6 transporter activity, displays reduced plasma anti-mineralization capacity due to reduced fetuin-A and matrix gla-protein (MGP) levels. MGP requires to be activated by gamma-glutamyl carboxylation, a vitamin K-dependent reaction, to serve in an anti-mineralization role in the peripheral connective tissue cells. Although the molecules transported from the hepatocytes to circulation by ABCC6 in vivo remain unidentified, it has been hypothesized that a critical vitamin K derivative, such as reduced vitamin K conjugated with glutathione, is secreted to circulation physiologically, but not in the absence of ABCC6 transporter activity. As a result, activation of MGP by gamma-glutamyl carboxylase is diminished, allowing slow yet progressive mineralization of connective tissues characteristic of PXE. Understanding of the pathomechanistic details of PXE provides a basis for the development of targeted molecular therapies for this currently intractable disease.
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Affiliation(s)
- Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Chung HJ, Uitto J. Type VII collagen: the anchoring fibril protein at fault in dystrophic epidermolysis bullosa. Dermatol Clin 2010; 28:93-105. [PMID: 19945621 DOI: 10.1016/j.det.2009.10.011] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Type VII collagen is a major component of the anchoring fibrils of the dermal-epidermal adhesion on the dermal side at the lamina densa/papillary dermis interface. Dystrophic epidermolysis bullosa (DEB) emerged as a candidate for type VII collagen mutations becausing anchoring fibrils were shown to be morphologically altered, reduced in number, or completely absent in patients with different forms of DEB. Circulating autoantibodies recognize type VII collagen epitopes in epidermolysis bullosa acquisita. The suggestion that type VII collagen is required for human epidermal tumorigenesis relates to the increasing numbers of life-threatening complications associated with developing squamous cell carcinomas because of the extended life span of affected individuals with recessive DEB.
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Affiliation(s)
- Hye Jin Chung
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, and Jefferson Institute of Molecular Medicine, Thomas Jefferson University, 233 South 10th Street, Suite 450 BLSB, Philadelphia, PA 19107, USA
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Abstract
Epidermolysis bullosa (EB) with pyloric atresia (PA) is a rare form of EB. This article describes the clinical and pathologic features and molecular genetics of EB-PA, the mutations in the alpha(6)beta(4) integrin and plectin genes that cause EB-PA, and the clinical implications of molecular genetics on EB-PA.
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Affiliation(s)
- Hye Jin Chung
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, 233 South 10th Street, Suite 450 BLSB, Philadelphia, PA 19107, USA
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