David R Garrod

The University of Manchester · Faculty of Life Sciences

The desmosomal cadherins (DCs) are adhesion molecules of desmosomes, intercellular junctions of epithelia and cardiac muscle. DCs have the unique ability to adopt a hyperadhesive state that is characterised by enhanced stability and adhesive strength. Hyperadhesion is important in embryonic development and wound healing, and DC expression is tightl...

Significance We present here an entirely novel concept in the field of cell–cell adhesion, whereby the flexibility of the extracellular domains of cadherin molecules determines the characteristics and behavior of intercellular junctions. The structure of the ectodomain of the desmosomal cadherin desmoglein 2 shows it is flexible in its calcium-boun...

Blocking the bioactivity of allergens is conceptually attractive as a small-molecule therapy for allergic diseases but has not been attempted previously. Group 1 allergens of house dust mites (HDM) are meaningful targets in this quest because they are globally prevalent and clinically important triggers of allergic asthma. Group 1 HDM allergens are...

Desmosomes are intercellular adhesive junctions of major importance for tissue integrity. To allow cell motility and migration they are down-regulated in epidermal wound healing. Electron microscopy indicates that whole desmosomes are internalised by cells in tissues, but the mechanism of down-regulation is unclear. In this paper we provide an over...

The Nrf2 transcription factor controls the expression of genes involved in the antioxidant defense system. Here, we identified Nrf2 as a novel regulator of desmosomes in the epidermis through the regulation of microRNAs. On Nrf2 activation, expression of miR-29a and miR-29b increases in cultured human keratinocytes and in mouse epidermis. Chromatin...

Hyper-adhesion is a unique, strongly adhesive form of desmosomal adhesion that functions to maintain tissue integrity. In this short review, we define hyper-adhesion, summarise the evidence for it in culture and in vivo, discuss its role in development, wound healing, and skin disease, and speculate about its molecular and cellular basis.

Abstract Desmosomes are intercellular junctions that provide strong adhesion or hyper-adhesion in tissues. Here, we discuss the molecular and structural basis of this with particular reference to the desmosomal cadherins (DCs), their isoforms and evolution. We also assess the role of DCs as regulators of epithelial differentiation. New data on the...

Abbreviations: DP, desmoplakin; Dsc, desmocollin; Dsg, desmoglein

During embryonic development tissues remain malleable to participate in morphogenetic movements but on completion of morphogenesis they must acquire the toughness essential for independent adult life. Desmosomes are cell-cell junctions that maintain tissue integrity especially where resistance to mechanical stress is required. Desmosomes in adult t...

Non-healing wounds cause considerable patient morbidity and represent a significant economic burden. Central to wound repair is re-epithelialization, a crucial process involving the modulation of cell adhesion to allow keratinocyte migration to cover the exposed underlying tissues. The cellular mechanisms regulating the earliest stages of re-epithe...

E-cadherin, a classical cadherin, is an adhesion receptor in adherens junctions and has important functions in cell-cell adhesion and cell signalling. Recently we reported that a desmosomal cadherin, desmoglein 3 (Dsg3), an autoantigen in pemphigus vulgaris (PV), associates with E-cadherin and activates Src, which results in tyrosine phosphorylatio...

The desmosomal cadherins (DCs), desmocollin (Dsc) and desmoglein (Dsg), are the adhesion molecules of desmosomes, intercellular adhesive junctions of epithelia and cardiac muscle. Both the DCs and desmosomes have demonstrably essential roles in mammalian development. In order to initiate their study in a more tractable developmental system we have...

Sequences of zebrafish desmosomal cadherins. The file contains the sequences of zfDsc, zfDsgα and zfDsgβ, and an amino acid identity comparison between zfDsgα and β.

Evidence has accumulated that changes in intracellular signaling downstream of desmoglein 3 (Dsg3) may have a significant role in epithelial blistering in the autoimmune disease pemphigus vulgaris (PV). Currently, most studies on PV involve passive transfer of pathogenic antibodies into neonatal mice that have not finalized epidermal morphogenesis,...

Phosphorylated Smad2/3 translocates to the nucleus in response to TGFβ2 ligand. BPH-1 cells grown in monolayer were treated with 5 ng/ml TGFβ2 (Sigma) ligand for 24 hours, a dose known to be effective for cell culture [60]. Before treatment phosphorylated smad 2/3 (green) was found in the cytoplasm and after treatment was found in the nucleus (DAPI...

Functional pathway analysis using Pathway Express to determine significant KEGG pathways occurring in the stroma in response to the presence of 3D BPH-1 cells cultured in Matrigel. The 1.5 fold change p<0.05 list of probe changes was used to determine the most significant KEGG pathways changing in stroma in the presence of BPH-1 spheroids. Pathways...

Imaging E-cadherin and desmosomes in BPH-1 acini. A) E-cadherin expression (red) at the basal edge of a BPH-1 acinus, showing intense staining of cellular protrusions. Confocal microscopy images, x63 magnification, bars = 20 µm. B) desmoglein expression (red) in BPH-1 acini was punctate manner. Confocal microscopy images, ×63 magnification, bars =...

Primers and probes for real time RT-PCR. (DOC)

RNA expression of desmosomal isoforms in BPH-1 spheroids. A) Semi-quantitative RT-PCR showing the relative expression of RNA isolated from BPH-1 spheroids for 7 days culture. The fold difference in gene expression was expressed relative to GAPDH for equal loadings of 250ng cDNA. Error bars represent standard deviation of three independent experimen...

Dye exclusion from the lumen of BPH-1 spheroids. BPH-1 cells were grown in Matrigel with or without stroma for 7 days. FITC 4 kDa dye (black bars) or rhodamine 70 kDa dye (clear bars) was added for 24 hours, after which spheres were removed from matrigel and trypsinised to release the dyes within the lumen. Measurement of dyes was performed with a...

Tissue sample details. The sample identity (ID) is listed, along with the diagnosis of the patient (BPH, benign prostatic hyperplasia), age and batch of Matrigel. (DOC)

Primers for RT-PCR. (DOC)

Significant differential expression of stromal extracellular matrix genes in response to 3D epithelial cultures. The probes for extracellular matrix genes according to the gene ontology database were exported from the fold change p<0.05 array list. The 19 most differentially expressed genes from the GO:0031012 extracellular matrix genes list were e...

Primary antibodies and dilutions for immunofluorescence and Western Blotting. (DOC)

Secondary antibodies and dilutions for immunofluorescence and Western blotting. (DOC)

Background: Cell shape and tissue architecture are controlled by changes to junctional proteins and the cytoskeleton. How tissues control the dynamics of adhesion and cytoskeletal tension is unclear. We have studied epithelial tissue architecture using 3D culture models and found that adult primary prostate epithelial cells grow into hollow acinus...

Epithelia are found at the interfaces between body compartments where they act as selective permeability barriers that maintain the unique composition of the compartments on either side. Epithelial barrier function is dependent on tight junctions (TJs), which seal the intercellular or paracellular spaces but may permit selective permeability. In si...

Desmosomes and adherens junctions are cadherin-based protein complexes responsible for cell-cell adhesion of epithelial cells. Type 1 cadherins of adherens junctions show specific homophilic adhesion that plays a major role in developmental tissue segregation. The desmosomal cadherins, desmocollin and desmoglein, occur as several different isoforms...

Desmoglein 3 (Dsg3), a desmosomal adhesion protein, is expressed in basal and immediate suprabasal layers of skin and across the entire stratified squamous epithelium of oral mucosa. However, increasing evidence suggests that the role of Dsg3 may involve more than just cell-cell adhesion. To determine possible additional roles of Dsg3 during epithe...

Desmosomes are intercellular junctions whose primary function is strong intercellular adhesion, known as hyperadhesion. In the present review, we discuss how their structure appears to support this function as well as how they are assembled and down-regulated. Desmosomal components also have signalling functions that are important in tissue develop...

The structure, function, and regulation of desmosomal adhesion in vivo are discussed. Most desmosomes in tissues exhibit calcium-independent adhesion, which is strongly adhesive or "hyperadhesive". This is fundamental to tissue strength. Almost all studies in culture are done on weakly adhesive, calcium-dependent desmosomes, although hyperadhesion...

Conventional approaches for ultrastructural high-resolution imaging of biological specimens induce profound changes in bio-molecular structures. By combining tissue cryo-sectioning with non-destructive atomic force microscopy (AFM) imaging we have developed a methodology that may be applied by the non-specialist to both preserve and visualize bio-m...

The cysteine peptidase activity of group 1 house dust mite allergens is important for their allergenicity and may offer new therapeutic targets for allergy treatment. Hitherto, the design of specific inhibitors has been impeded because the availability of pure, fully active allergens has limited the implementation of drug screening campaigns. Simil...

Ephs and ephrins are cell surface receptors that bind to each other and initiate distinct, bidirectional signalling pathways in processes known as forward (Eph) and reverse (ephrin) signalling. Previous work had shown that the loss of ephrinB1 protein alone or compound loss of EphB2 and EphB3 leads to cleft palate. Because of the bidirectional sign...

Nectin-1 is a member of a sub-family of immunoglobulin-like adhesion molecules and a component of adherens junctions. In the current study, we have shown that mice lacking nectin-1 exhibit defective enamel formation in their incisor teeth. Although the incisors of nectin-1-null mice were hypomineralized, the protein composition of the enamel matrix...

Desmosomes are intercellular junctions responsible for strong cell-cell adhesion in epithelia and cardiac muscle. Numerous studies have shown that the other major type of epithelial cell adhesion, the adherens junction, is destabilized by src-induced tyrosine phosphorylation of two of its principal components, E-cadherin and beta-catenin. Here we s...

We have developed a new concept of cell-cell adhesion termed 'hyper-adhesion', the very strong adhesion adopted by desmosomes. This uniquely desmosomal property accounts for their ability to provide the intercellular links in the desmosome-intermediate filament complex. These links are targeted by diseases, resulting in disruption of the complex wi...

IntroductionWhat Happens During Sensitization to Inhaled Allergens?Structure of the Airway Mucosa and its Relevance to Allergic SensitizationHypothesis of Intercellular Junctions as Targets for House-Dust Mite AllergensMolecular and Functional Biological Properties of House-Dust Mite AllergensHouse-Dust Mite Proteinase Allergens and Epithelial Morp...

Desmosomes are intercellular junctions of epithelia and cardiac muscle. They resist mechanical stress because they adopt a strongly adhesive state in which they are said to be hyper-adhesive and which distinguishes them from other intercellular junctions; desmosomes are specialised for strong adhesion and their failure can result in diseases of the...

Desmosomes are intercellular junctions found in epithelia and some other tissues. Their primary function is strong cell-cell adhesion. They also link the intermediate filament (IF) cytoskeletons between cells and have roles in cell signaling, tissue morphogenesis, and wound repair. Because of their size (0.2-0.5 microm), details of their ultrastruc...

Asthma and allergic rhinitis are significant, increasing causes of morbidity worldwide. Pollen, a major cause of seasonal rhinitis/conjunctivitis, carries proteolytic enzymes on its surface. We showed previously that peptidase allergens from house dust mites compromise epithelial barrier function by degrading the extracellular domains of the tight...

Studies in vivo have shown that the cysteine peptidase activity of group 1 house dust mite allergens contributes to their allergenicity. These allergens are synthesized initially as proenzymes and removal of the propiece is necessary to unmask their proteolytic activity. In related C1 family cysteine peptidases of enzyme clan CA, liberated propiece...

Biological behaviour of an implant, such as osseointegration, depends on both the chemical composition and the morphology of the surface of the implant. This paper reports the surface modification of Ti–6Al–4V – which is widely used in implantation – by Nd:YAG (λ = 1064 nm, τ = 100 ns) laser irradiation in order to enhance biointegration. Surface p...

New studies have shown that tricalcium silicate powder is a bioactive material and can encourage bone–implant integration. This paper reports the synthesis of Ca2SiO4 coating on Ti–6Al–4V samples by laser irradiation under submerged conditions. The results of using a 160–1500 LDL 1.5kW diode laser (rectangular spot=2.5mm×3.5mm, λ=808 and 940nm with...

Desmosomes in tissues are resistant to disruption by chelation of extracellular calcium. It has been suggested that this represents a hyper-adhesive state of these intercellular junctions that is crucial for the maintenance of epidermal integrity. Desmosomes change to a lower affinity, calcium-dependent adhesive state when cells are cultured at low...

The resistance of tissues to physical stress is dependent upon strong cell-cell adhesion in which desmosomes play a crucial role. We propose that desmosomes fulfil this function by adopting a more strongly adhesive state, hyper-adhesion, than other junctions. We show that the hyper-adhesive desmosomes in epidermis resist disruption by ethylene glyc...

Impairment of the gut epithelial barrier by agents such as IFNgamma may play a key role in the pathogenesis of inflammatory disorders by increasing the paracellular penetration of luminal macromolecules, potentially including bacterial antigens. Owing to limitations of current paracellular probes, little is known about the precise functional change...

Desmosomal adhesion is important for the integrity and protective barrier function of the epidermis and is disregulated during carcinogenesis. Strong adhesion between keratinocytes is conferred by the desmosomal cadherins, desmocollin (Dsc) and desmoglein. These constitute two gene families, members of which are differentially expressed in epiderma...

We have shown previously that human desmocollin (Dsc) 1 is recognized by IgA autoantibodies of subcorneal pustular dermatosis (SPD) type IgA pemphigus. However, the presence of IgG anti-Dsc autoantibodies is still controversial, and antibodies to Dsc2 and Dsc3 have not been clearly identified. To investigate this by producing recombinant proteins c...

Desmocollins (Dscs) are desmosomal cadherins that exhibit differentiation-specific patterns of expression in the epidermis. Dsc3 expression is strongest in basal cell layers, whereas Dsc1 is largely confined to upper, terminally differentiating strata. To understand better the processes by which Dsc expression is regulated in the epidermis, we have...

We have used immunohistochemistry to test the hypothesis that components of the desmosome are disrupted during neoplastic progression of squamous epithelial cells in the uterine cervix. Sections of normal cervix and squamous intraepithelial lesions (SILs) were immunostained for desmosomal proteins and glycoproteins, and results were assessed using...

We have investigated the influence of mast cells on the barrier function of intestinal epithelium during nematode infection. Trichinella spiralis infection induces a strong type 2 cytokine-mediated inflammation, resulting in a critical mucosal mastocytosis that is known to mediate expulsion of the parasites from the intestine. The host response to...

Loss of epithelial cell polarity, which can arise following disruption of tight junctions (TJs), is a precursor to the care-fully orchestrated removal of moribund cells from epithelia in apoptosis. Ordinarily, this cycle of events has minimally disruptive effects on the function of the epithelial barrier, but some agents have been identified that i...

New evidence from blocking desmosomal adhesion with anti-adhesion peptides reveals a role for desmosomes in cell positioning in morphogenesis. Desmosomal adhesion is necessary for the stability of adherens junctions in epithelial cell sheets. Knockout and mis-expression of desmosomal cadherins in mice suggests that they may function directly or ind...

Cultivation of human parotid glands in serum-free medium (Ca(2+) concentration, 0.2 mM) with growth supplements resulted in isolation of a homogeneous population of epithelial cells without any mesenchymal cells. The isolated cells showed an undifferentiated phenotype with scant cytoplasmic organelles, and low levels of alpha-amylase expression. Th...

The desmoglein 1 (Dsg1) and desmocollin 1 (Dsc1) isoforms of the desmosomal cadherins are expressed in the suprabasal layers of epidermis, whereas Dsg3 and Dsc3 are more strongly expressed basally. This differential expression may have a function in epidermal morphogenesis and/or may regulate the proliferation and differentiation of keratinocytes....

Desmosomes are adhesive intercellular junctions of epithelia and cardiac muscle. They have an essential function in maintaining the integrity of tissues, which is compromised in human genetic and autoimmune disease that targets desmosomal components. Recent evidence (1) suggests new roles for the function of desmosomal adhesion in tissue morphogene...

The desmosomal cadherin desmocollin (Dsc)1 is expressed in upper epidermis where strong adhesion is required. To investigate its role in vivo, we have genetically engineered mice with a targeted disruption in the Dsc1 gene. Soon after birth, null mice exhibit flaky skin and a striking punctate epidermal barrier defect. The epidermis is fragile, and...

Desmosomes are intercellular junctions of epithelia and are of widespread importance in the maintenance of tissue architecture. We provide evidence that desmosomal adhesion has a function in epithelial morphogenesis and cell-type-specific positioning. Blocking peptides corresponding to the cell adhesion recognition (CAR) sites of desmosomal cadheri...

There have been only a few studies of how allergens cross the airway epithelium to cause allergic sensitization. House dust mite fecal pellets (HDMFP) contain several proteolytic enzymes. Group 1 allergens are cysteine peptidases, whilst those of groups 3, 6 and 9 have catalytic sites indicative of enzymes that mechanistically behave as serine pept...

The desmosomal glycoproteins desmoglein (Dsg) and desmocollin (Dsc) are members of the cadherin family of cell adhesion molecules. They play an important role in epithelial adhesion. To observe the distribution pattern of Dsg in esophageal squamous cell carcinomas (SCC), immunohistochemical and immunoelectron microscopic analyses were performed. Im...

Dynamic regulation of intercellular junctions is an essential aspect of many developmental, reproductive, and physiological processes. We have shown that expression of the desmosomal protein desmoplakin decreases in the luminal uterine epithelium during the preimplantation period of pregnancy in mice. By the time of implantation (between Days 4.5 a...

In mice, monoclonal antibody (mAb) to the αl integrin abrogate gastro-intestinal damage during graft-versus-host-disease (GVHD), suggesting anti αl mAb as candidates for treatment in humans as wellOur current data show that one such reagent, mAb 1B3.1, when immobilized to plastic wells via rabbit- anti murine (ram) immunoglobulin (Ig) induces a pro...

Tight junctions (TJs) make a vital contribution to the barrier properties of the airway lining. Opening of TJs, or their frank cleavage, is suspected as a pathophysiological event in the lung, but research into the cellular and molecular mechanisms involved has been impeded by technical limitations of available experimental models. The authors have...

House dust mite allergen Der p 1 is a cysteine peptidase. Previously, we have suggested that the proteolytic activity of this allergen may contribute to asthma by damaging the barrier formed by the airways epithelium. The present study applied novel techniques to compare changes in permeability with quantitative events in tight junctions (TJs) and...