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Alain Hovnanian - One of the best experts on this subject based on the ideXlab platform.
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klk5 inactivation reverses cutaneous hallmarks of netherton syndrome
PLOS Genetics, 2015Co-Authors: Laetitia Furio, Iacovos P Michael, Georgia Sotiropoulou, Georgios Pampalakis, Andras Nagy, Alain HovnanianAbstract:Netherton Syndrome (NS) is a rare and severe autosomal recessive skin disease which can be life-threatening in infants. The disease is characterized by extensive skin desquamation, inflammation, allergic manifestations and hair shaft defects. NS is caused by loss-of-function mutations in SPINK5 encoding the LEKTI serine protease inhibitor. LEKTI deficiency results in unopposed activities of kallikrein-related peptidases (KLKs) and aberrantly increased proteolysis in the epidermis. Spink5⁻/⁻ mice recapitulate the NS phenotype, display enhanced epidermal Klk5 and Klk7 protease activities and die within a few hours after birth because of a severe skin barrier defect. However the contribution of these various proteases in the physiopathology remains to be determined. In this study, we developed a new murine model in which Klk5 and Spink5 were both knocked out to assess whether Klk5 deletion is sufficient to reverse the NS phenotype in Spink5⁻/⁻ mice. By repeated intercrossing between Klk5⁻/⁻ mice with Spink5⁻/⁻ mice, we generated Spink5⁻/⁻Klk5⁻/⁻ animals. We showed that Klk5 knock-out in LEKTI-deficient newborn mice rescues neonatal lethality, reverses the severe skin barrier defect, restores epidermal structure and prevents skin inflammation. Specifically, using in situ zymography and specific protease substrates, we showed that Klk5 knockout reduced epidermal proteolytic activity, particularly its downstream targets proteases KLK7, KLK14 and ELA2. By immunostaining, western blot, histology and electron microscopy analyses, we provide evidence that desmosomes and corneodesmosomes remain intact and that epidermal differentiation is restored in Spink5⁻/⁻Klk5⁻/⁻. Quantitative RT-PCR analyses and immunostainings revealed absence of inflammation and allergy in Spink5⁻/⁻Klk5⁻/⁻ skin. Notably, Il-1β, Il17A and Tslp levels were normalized. Our results provide in vivo evidence that KLK5 knockout is sufficient to reverse NS-like symptoms manifested in Spink5⁻/⁻ skin. These findings illustrate the crucial role of protease regulation in skin homeostasis and inflammation, and establish KLK5 inhibition as a major therapeutic target for NS.
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netherton syndrome skin inflammation and allergy by loss of protease inhibition
Cell and Tissue Research, 2013Co-Authors: Alain HovnanianAbstract:Netherton syndrome (NS) is a rare autosomal recessive skin disease with severe skin inflammation and scaling, a specific hair shaft defect and constant allergic manifestations. NS is caused by loss-of-function mutations in SPINK5 (serine protease inhibitor of kazal type 5) encoding LEKTI-1 (lympho-epithelial kazal type related inhibitor type 5) expressed in stratified epithelia. In vitro and in vivo studies in murine models and in NS patients have cast light on the pathogenesis of the disease and shown that LEKTI deficiency results in unopposed kallikrein-related peptidase 5 (KLK5) and KLK7 activities and to the overactivity of a new epidermal protease, elastase 2 (ELA2). Two main cascades initiated by KLK5 activity have emerged. One results in desmoglein 1 degradation and desmosome cleavage leading to stratum corneum detachment. KLK5 also activates KLK7 and ELA2, which contribute to a defective skin barrier. This facilitates allergen and microbe penetration and generates danger signals leading to caspase 1 activation and the production of active interleukin-1β. In parallel, KLK5 activates a specific cascade of allergy and inflammation by activating protease-activated receptor-2 (PAR-2) receptors. PAR-2 activation triggers the production of the major pro-Th2 cytokine TSLP (thymic stromal lymphopoietin) and several inflammatory cytokines, including tumour necrosis factor-α. Levels of thymus and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) also contribute to allergy in a PAR-2-independent manner. Patient investigations have confirmed these abnormalities and revealed a wide spectrum of disease expression, sometimes associated with residual LEKTI expression. These results have demonstrated that the tight regulation of epidermal protease activity is essential for skin homeostasis and identified new targets for therapeutic intervention. They also provide a link with atopic dermatitis through deregulated protease activity, as recently supported by functional studies of the E420K LEKTI variant.
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The 420K LEKTI variant alters LEKTI proteolytic activation and results in protease deregulation: implications for atopic dermatitis
Human molecular genetics, 2012Co-Authors: Paola Fortugno, Alain Hovnanian, Giovanna Zambruno, Laetitia Furio, Massimo Teson, Matteo Berretti, May El Hachem, Marina D'alessioAbstract:Lymphoepithelial Kazal-type related inhibitor (LEKTI) is a multidomain serine protease inhibitor which plays a central role in skin permeability barrier and allergy. Loss-of-function mutations in the LEKTI encoding gene SPINK5 cause Netherton syndrome, a rare and severe genetic skin disease with a profound skin barrier defect and atopic manifestations. Several studies also reported genetic association between the multifactorial disease atopic dermatitis (AD) and a frequent and non-conservative LEKTI variant, E420K, in different populations. Here, we provide evidence that the 420K variant impacts on LEKTI function by increasing the likelihood of furin-dependent LEKTI precursor cleavage within the linker region D6-D7. This results in the reversal of the cleavage priorities for LEKTI proteolytic activation and prevents the formation of the LEKTI fragment D6D9 known to display the strongest inhibitory activity against kallikrein (KLK) 5-mediated desmoglein-1 (DSG1) degradation. Using in situ and gel zymographies, we show that the modification of the subtle balance in LEKTI inhibitory fragments leads to enhanced KLK5, KLK7 and elastase-2 (ELA-2) activities in 420KK epidermis. By immunohistochemistry and western blot analyses, we found that increased epidermal protease activity correlates with reduced DSG1 protein expression and accelerated profilaggrin proteolysis. All changes determined by the presence of residue 420K within the LEKTI sequence likely contribute to defective skin barrier permeability. Remarkably, LEKTI 420KK epidermis displays an increased expression of the proallergic cytokine thymic stromal lymphopoietin (TSLP). This is the first functional evidence supporting association studies which identified the 420K LEKTI variant as a predisposing factor to AD, in combination with other genetic and environmental factors.
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protease deregulation: implications for atopic dermatitis
2012Co-Authors: Paola Fortugno, Giovanna Zambruno, Laetitia Furio, Massimo Teson, Matteo Berretti, May El Hachem, Alain HovnanianAbstract:g.oxfordjournals.org/ D ow nloaded from 2 Lymphoepithelial Kazal-type related inhibitor (LEKTI) is a multidomain serine protease inhibitor which plays a central role in skin permeability barrier and allergy. Loss-of-function mutations in the LEKTI encoding gene SPINK5 cause Netherton syndrome, a rare and severe genetic skin disease with a profound skin barrier defect and atopic manifestations. Several studies also reported genetic association between the multifactorial disease atopic dermatitis (AD) and a frequent and non-conservative LEKTI variant, E420K, in different populations. Here we provide evidence that the 420K variant impacts on LEKTI function by increasing the likelihood of furin-dependent LEKTI precursor cleavage within linker region D6-D7. This results in reversal of the cleavage priorities for LEKTI proteolytic activation and prevents the formation of the LEKTI fragment D6D9 known t
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par2 inactivation inhibits early production of tslp but not cutaneous inflammation in netherton syndrome adult mouse model
Journal of Investigative Dermatology, 2010Co-Authors: Anais Briot, Céline Deraison, Matthieu Lacroix, Aurelie Robin, Martin Steinhoff, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genodermatosis characterized by abnormal scaling and constant atopic manifestations. NS is caused by mutations in SPINK5 (Serine Protease INhibitor Kazal-type 5), which encodes LEKTI (LymphoEpithelial Kazal Type-related Inhibitor). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. Whereas a skin barrier defect is generally regarded as a major cause for atopy, we previously identified a cell-autonomous signaling cascade that triggers pro-Th2 cytokine thymic stromal lymphopoietin (TSLP) production in LEKTI-deficient epidermis. This signaling is initiated by unrestricted kallikrein 5 (KLK5) activity, which directly activates proteinase-activated receptor 2 (PAR2)-mediated expression of TSLP and favors a cutaneous proallergic microenvironment independently of the environment and of the adaptive immune system. To further confirm these results in vivo, we generated Spink5/Par2 double knockout (DKO) mice. At embryonic day 19.5, these mice display a dramatic decrease in TSLP expression, although stratum corneum detachment persists, confirming the role of the KLK5–PAR2 cascade in TSLP-mediated early proallergic signaling. However, deletion of Par2 in adult DKO-grafted skin does not rescue the inflammatory phenotype probably resulting from stratum corneum detachment. We conclude that several mechanisms trigger and maintain the inflammatory phenotype in NS. These include skin barrier impairment, mechanical stress secondary to stratum corneum detachment, as well as protease-induced proinflammatory and proallergic pathways, including PAR2-mediated overexpression of TSLP.
Arumugam Jayakumar - One of the best experts on this subject based on the ideXlab platform.
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Expression of LEKTI correlates with PNI and LVI in SCC of the oral tongue and mechanism of LEKTI loss in HNSCC
MOJ Proteomics & Bioinformatics, 2015Co-Authors: Thomas D. Shellenberger, Gary L Clayman, Mitchell J. Frederick, Ying C. Henderson, Ya'an Kang, Karthik Jayakumar, Rena Janarthanan, Rajendra Prasad, Arumugam JayakumarAbstract:Expression of Lympho-Epithelial Kazal-Type-Inhibitor (LEKTI), a broad spectrum protease inhibitor, is dysregulated in head and neck squamous cell carcinomas (HNSCC) and HNSCC cell lines. Here, we investigated expression of LEKTI in primary tumor specimens of 81 patients with SCC of the oral tongue in correlation with pathologic findings and clinical outcomes. IHC analyses have shown that LEKTI expression is negative in 31, intermediate in 44, and strong in 6 patients. Correlative analyses between LEKTI expression and perineural Invasion (PNI) and lymphovascular invasion (LVI) demonstrated that the relative risk of PNI and LVI were 3.2 (95% CI, 1.2 to 8.9, p = 0.007 by Chi Square Test) and 6.0 (95% CI 1.2 to 40.8, p = 0.01 by Fisher’s Exact Test) respectively in patients with LEKTI-negative tumors compared to those with LEKTI-positive tumors. Kaplan-Meier estimates showed that patients with LEKTI-negative expression had a 20% increased risk of disease recurrence (HR 1.19 and 95% CI 0.61 to 2.33, p = 0.23 by Log rank test) and an 80% increased risk of death from all causes (HR 1.78 and 95% CI 0.34 to 9.41, p = 0.48 by Log rank test). Analysis of the covariates for disease recurrence and death in tongue cohort found no significant differences in age, gender, T-stage, grade, N-stage, and postoperative treatment between patients with LEKTI-negative and LEKTI-positive tumors. Further, we present evidence that transcriptional regulation is a very likely mechanism accounting for loss of LEKTI mRNA and protein from HNSCC. These data confirm our previous in vitro and orthotopic model of tongue cancer findings and shed new light on mechanisms of PNI and LVI in HNSCC.
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Molecular and Biochemical Properties of Lympho- Epithelial Kazal-Type-Inhibitor (LEKTI)
MOJ Proteomics & Bioinformatics, 2015Co-Authors: Arumugam Jayakumar, Mitchell J. Frederick, Thomas D. Shellenberger, Ying C. Henderson, Ya'an Kang, Venugopal Radjendirane, Katrina Briggs, David Tran, Karthik Jayakumar, Gary L ClaymanAbstract:Here, we review the literature on the molecular and biochemical properties of Lympho-Epithelial Kazal-Type-Inhibitor (LEKTI). Serine Protease Inhibitor Kazal- type 5 (SPINK5) gene encodes three different LEKTI isoforms. These isoforms are organized into a typical 15, longer than 15 and shorter than 15 inhibitory domains consisting of 1064, 1094 and 916 residues respectively. LEKTI isoforms synthesized as pro-LEKTI proteins are processed intracellular and secreted as bioactive LEKTI fragments into blood. LEKTI potently inhibits activity of plasmin, subtilisin A, cathepsin G, elastase, trypsin, kallikrein (KLK) 5, KLK6, KLK7, KLK13, and KLK14 to varied extents. Mutations in SPINK5 gene resulting in decreased LEKTI function and increased KLK activity causes Netherton syndrome (NS). Low SPINK5 expression/LEKTI function is also associated with Head and Neck Squamous Cell carcinoma (HNSCC), chronic rhinosinusitis and asthma. Thus restoring SPINK5 expression/LEKTI function in NS, HNSCC and asthma holds therapeutic promise.
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LEKTI, a physiological inhibitor of multiple serine proteinases, suppresses perineural and lymphovascular invasion of human head and neck cancer cells in a mouse orthotopic model
MOJ Proteomics & Bioinformatics, 2014Co-Authors: Arumugam Jayakumar, Thomas D. Shellenberger, Venugopal Radjendirane, Katrina Briggs, Gary L ClaymanAbstract:Serine Protease Inhibitor Kazal-type 5 (SPINK5) gene encodes 3 different LymphoEpithelial Kazal-Type-Inhibitor (LEKTI) isoforms. We identified and cloned LEKTI by its constitutive expression in normal oral mucosa and its loss of expression in matched tumor specimens of patients with head and neck squamous cell carcinoma (HNSCC). Stable re-expression of LEKTI in HNSCC OSC19 cells resulted in reduced migration and invasionand enhanced adhesion on variety of ECM substrates in vitrowith a concomitant reduction inexpression of endogenous MMP-14, MMP-8, KLK5, and ADAM8. Here, we sought to determine the consequences of LEKTI re-expression on the in vivo changes in the tumor growth and invasion using an orthotopic model of tongue cancer. In the tongue tumors of mice, lymphovascular invasion or perineural spread was found in 100% of tumors derived from parental cell lines but was almost totally absent in all tumors derived from LEKTI-expressing clones. Our work suggests that loss of LEKTI expression in primary tumors might correlate with aggressive biologic behavior and restoration of LEKTI expression by pharmacologic means might be beneficial for patients with HNSCC.
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LEKTI, A Physiological Inhibitor of Multiple Serine Proteinases, Blocks Migration and Invasion of Head and Neck Squamous Cell Carcinoma (HNSCC) Cells
MOJ Proteomics & Bioinformatics, 2014Co-Authors: Arumugam Jayakumar, Ying C. Henderson, Ya'an Kang, Venugopal Radjendirane, Rani Chattopadhyay, Katrinabriggs, Latha Ramdas, Shikha Sharma, Thomas D. ShellenbergerAbstract:Serine Protease Inhibitor Kazal-type 5 (SPINK5) gene encodes 3 different Lympho- Epithelial Kazal-Type-Inhibitor (LEKTI) isoforms which are organized into longer than 15, 15, and 13 inhibitory domains. We identified LEKTI by its constitutive expression in normal oral mucosa and lost or down regulated expression in matched tumor specimens of patients with head and neck squamous cell carcinoma (HNSCC). Previously, we showed that recombinant full-length LEKTI and rLEKTI fragments inhibit the activity of plasmin, subtilisin A, cathepsin G, neutrophil elastase, trypsin, caspase 14, and kallikreins (KLK) 5, 6, 7, 13, and 14 to varied extents. Here, we show that LEKTI protein is absent in HNSCC OSC19, Tu138, Tu177, and UMSCC1 lines. We then determined the consequences of LEKTI re-expression on migration and invasion, adhesion and gene expression profile of HNSCCOSC19 and UMSCC1 lines. We demonstrate that LEKTI expressing OSC19 and UMSCC1 clones show markedly reduced migration and invasion. Moreover, LEKTI expressing OSC19 clones show striking morphological changes and enhanced adhesionon type I, III, IV, and V collagens, fibronectin, and laminin5.In addition, we show that exogenous r-LEKTI blocks migration of OSC19-parental cells in a dose and time dependent manner. Microarray analysis identified 186 genes which are differentially regulated in both OSC19 LEKTI clones. MMP-14, KLK5, and ADAM8 are down regulated while MMP-3, LEKTI, DSC2 and DSC3are up-regulated in OSC19 LEKTI clones. RT-PCR and Western blot results confirmed microarray results for MMP-14 and MMP-3in OSC19 LEKTI clones. In addition we discover that MMP-9 protein expression and pro-MMP-9 activity are severely reduced in LEKTI expressing clones as shown by WB and zymogram. Together, this work provides mechanistic insights into how loss of LEKTI protein expression promotes an invasive phenotype in HNSCC tumors.
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Current Status of LEKTI, a Physiological Inhibitor of Multiple Proteinases in the Skin - A Review
2014Co-Authors: Arumugam Jayakumar, Venugopal RadjendiraneAbstract:Serine Protease Inhibitor Kazal-type 5 (SPINK5) gene encodes 3 different LymphoEpithelial Kazal-Type-Inhibitor (LEKTI) isoforms, which differ in their C-terminal sequence, are organized into longer than 15, 15, and 13 inhibitory domains. Pro-LEKTI is processed intracellular and the bioactive LEKTI fragments are secreted. LEKTI shows a restricted expression pattern in skin, thymus, oral mucosa, vaginal epithelium, Bartholin's glands, pituitary, tonsils, and parathyroid glands. Recombinant full-length LEKTI and rLEKTI fragments inhibit the activity of plasmin, subtilisin A, cathepsin G, neutrophil elastase, trypsin, caspase 14, and kallikreins (KLK) 5, 6, 7, 13, and 14 (involved in skin desquamation and growth hormone processing) to varied extents. Loss-of-function 1 SMU Medical Journal ISSN : 2349 – 1604 (Volume – 1, No. 2, July 2014) Review Article SMU Medical Journal, Volume – 1, No. 2, July 2014 mutations, polymorphisms, and transcriptional inactivation of the cognate SPINK5 gene resulting in LEKTI loss or defective LEKTI processing is linked to Netherton syndrome (NS), head and neck squamous cell carcinomas (HNSCC), asthma, and chronic rhinosinusitis. Here, we give a brief review on the published work of LEKTI.
Céline Deraison - One of the best experts on this subject based on the ideXlab platform.
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par2 inactivation inhibits early production of tslp but not cutaneous inflammation in netherton syndrome adult mouse model
Journal of Investigative Dermatology, 2010Co-Authors: Anais Briot, Céline Deraison, Matthieu Lacroix, Aurelie Robin, Martin Steinhoff, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genodermatosis characterized by abnormal scaling and constant atopic manifestations. NS is caused by mutations in SPINK5 (Serine Protease INhibitor Kazal-type 5), which encodes LEKTI (LymphoEpithelial Kazal Type-related Inhibitor). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. Whereas a skin barrier defect is generally regarded as a major cause for atopy, we previously identified a cell-autonomous signaling cascade that triggers pro-Th2 cytokine thymic stromal lymphopoietin (TSLP) production in LEKTI-deficient epidermis. This signaling is initiated by unrestricted kallikrein 5 (KLK5) activity, which directly activates proteinase-activated receptor 2 (PAR2)-mediated expression of TSLP and favors a cutaneous proallergic microenvironment independently of the environment and of the adaptive immune system. To further confirm these results in vivo, we generated Spink5/Par2 double knockout (DKO) mice. At embryonic day 19.5, these mice display a dramatic decrease in TSLP expression, although stratum corneum detachment persists, confirming the role of the KLK5–PAR2 cascade in TSLP-mediated early proallergic signaling. However, deletion of Par2 in adult DKO-grafted skin does not rescue the inflammatory phenotype probably resulting from stratum corneum detachment. We conclude that several mechanisms trigger and maintain the inflammatory phenotype in NS. These include skin barrier impairment, mechanical stress secondary to stratum corneum detachment, as well as protease-induced proinflammatory and proallergic pathways, including PAR2-mediated overexpression of TSLP.
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Synthesis of the proteinase inhibitor LEKTI domain 6 by the fragment condensation method and regioselective disulfide bond formation.
Biopolymers, 2010Co-Authors: Zoe Vasileiou, Céline Deraison, Kostas K. Barlos, Dimitrios Gatos, Knut AdermannAbstract:Proteinase inhibitors are of high pharmaceutical interest and are drug candidates for a variety of indications. Specific kallikrein inhibitors are important for their antitumor activity and their potential application to the treatment of skin diseases. In this study we describe the synthesis of domain 6 of the kallikrein inhibitor Lympho-Epithilial Kazal-Type Inhibitor (LEKTI) by the fragment condensation method and site-directed cystine bridge formation. To obtain the linear LEKTI precursor, the condensation was best performed in solution, coupling the protected fragment 1-22 to 23-68. This method yielded LEKTI domain 6 of high purity and equipotent to the recombinantly produced peptide. © 2010 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 94: 339–349, 2010. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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Kallikrein 5 induces atopic dermatitis–like lesions through PAR2-mediated thymic stromal lymphopoietin expression in Netherton syndrome
The Journal of experimental medicine, 2009Co-Authors: Anais Briot, Céline Deraison, Chrystelle Bonnart, Celine Besson, Matthieu Lacroix, Aurelie Robin, Pierre Dubus, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
Aurelie Robin - One of the best experts on this subject based on the ideXlab platform.
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par2 inactivation inhibits early production of tslp but not cutaneous inflammation in netherton syndrome adult mouse model
Journal of Investigative Dermatology, 2010Co-Authors: Anais Briot, Céline Deraison, Matthieu Lacroix, Aurelie Robin, Martin Steinhoff, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genodermatosis characterized by abnormal scaling and constant atopic manifestations. NS is caused by mutations in SPINK5 (Serine Protease INhibitor Kazal-type 5), which encodes LEKTI (LymphoEpithelial Kazal Type-related Inhibitor). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. Whereas a skin barrier defect is generally regarded as a major cause for atopy, we previously identified a cell-autonomous signaling cascade that triggers pro-Th2 cytokine thymic stromal lymphopoietin (TSLP) production in LEKTI-deficient epidermis. This signaling is initiated by unrestricted kallikrein 5 (KLK5) activity, which directly activates proteinase-activated receptor 2 (PAR2)-mediated expression of TSLP and favors a cutaneous proallergic microenvironment independently of the environment and of the adaptive immune system. To further confirm these results in vivo, we generated Spink5/Par2 double knockout (DKO) mice. At embryonic day 19.5, these mice display a dramatic decrease in TSLP expression, although stratum corneum detachment persists, confirming the role of the KLK5–PAR2 cascade in TSLP-mediated early proallergic signaling. However, deletion of Par2 in adult DKO-grafted skin does not rescue the inflammatory phenotype probably resulting from stratum corneum detachment. We conclude that several mechanisms trigger and maintain the inflammatory phenotype in NS. These include skin barrier impairment, mechanical stress secondary to stratum corneum detachment, as well as protease-induced proinflammatory and proallergic pathways, including PAR2-mediated overexpression of TSLP.
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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Kallikrein 5 induces atopic dermatitis–like lesions through PAR2-mediated thymic stromal lymphopoietin expression in Netherton syndrome
The Journal of experimental medicine, 2009Co-Authors: Anais Briot, Céline Deraison, Chrystelle Bonnart, Celine Besson, Matthieu Lacroix, Aurelie Robin, Pierre Dubus, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
Chrystelle Bonnart - One of the best experts on this subject based on the ideXlab platform.
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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kallikrein 5 induces atopic dermatitis like lesions through par2 mediated thymic stromal lymphopoietin expression in netherton syndrome
Journal of Experimental Medicine, 2009Co-Authors: Céline Deraison, Chrystelle Bonnart, Anais Briot, Matthieu Lacroix, Aurelie RobinAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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Kallikrein 5 induces atopic dermatitis–like lesions through PAR2-mediated thymic stromal lymphopoietin expression in Netherton syndrome
The Journal of experimental medicine, 2009Co-Authors: Anais Briot, Céline Deraison, Chrystelle Bonnart, Celine Besson, Matthieu Lacroix, Aurelie Robin, Pierre Dubus, Alain HovnanianAbstract:Netherton syndrome (NS) is a severe genetic skin disease with constant atopic manifestations that is caused by mutations in the serine protease inhibitor Kazal-type 5 (SPINK5) gene, which encodes the protease inhibitor lymphoepithelial Kazal-type–related inhibitor (LEKTI). Lack of LEKTI causes stratum corneum detachment secondary to epidermal proteases hyperactivity. This skin barrier defect favors allergen absorption and is generally regarded as the underlying cause for atopy in NS. We show for the first time that the pro-Th2 cytokine thymic stromal lymphopoietin (TSLP), the thymus and activation-regulated chemokine, and the macrophage-derived chemokine are overexpressed in LEKTI-deficient epidermis. This is part of an original biological cascade in which unregulated kallikrein (KLK) 5 directly activates proteinase-activated receptor 2 and induces nuclear factor κB–mediated overexpression of TSLP, intercellular adhesion molecule 1, tumor necrosis factor α, and IL8. This proinflammatory and proallergic pathway is independent of the primary epithelial failure and is activated under basal conditions in NS keratinocytes. This cell-autonomous process is already established in the epidermis of Spink5−/− embryos, and the resulting proinflammatory microenvironment leads to eosinophilic and mast cell infiltration in a skin graft model in nude mice. Collectively, these data establish that uncontrolled KLK5 activity in NS epidermis can trigger atopic dermatitis (AD)–like lesions, independently of the environment and the adaptive immune system. They illustrate the crucial role of protease signaling in skin inflammation and point to new therapeutic targets for NS as well as candidate genes for AD and atopy.
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LEKTI fragments specifically inhibit klk5 klk7 and klk14 and control desquamation through a ph dependent interaction
Molecular Biology of the Cell, 2007Co-Authors: Arumugam Jayakumar, Céline Deraison, Chrystelle Bonnart, Frederic Lopez, Celine Besson, R A Robinson, Fredrik WagbergAbstract:LEKTI is a 15-domain serine proteinase inhibitor whose defective expression underlies the severe autosomal recessive ichthyosiform skin disease, Netherton syndrome. Here, we show that LEKTI is produced as a precursor rapidly cleaved by furin, generating a variety of single or multidomain LEKTI fragments secreted in cultured keratinocytes and in the epidermis. The identity of these biological fragments (D1, D5, D6, D8-D11, and D9-D15) was inferred from biochemical analysis, using a panel of LEKTI antibodies. The functional inhibitory capacity of each fragment was tested on a panel of serine proteases. All LEKTI fragments, except D1, showed specific and differential inhibition of human kallikreins 5, 7, and 14. The strongest inhibition was observed with D8-D11, toward KLK5. Kinetics analysis revealed that this interaction is rapid and irreversible, reflecting an extremely tight binding complex. We demonstrated that pH variations govern this interaction, leading to the release of active KLK5 from the complex at acidic pH. These results identify KLK5, a key actor of the desquamation process, as the major target of LEKTI. They disclose a new mechanism of skin homeostasis by which the epidermal pH gradient allows precisely regulated KLK5 activity and corneodesmosomal cleavage in the most superficial layers of the stratum corneum.
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etude fonctionnelle de LEKTI et de sa nouvelle cible l elastase 2 pancreatique
2007Co-Authors: Chrystelle BonnartAbstract:Le syndrome de Netherton (SN) est une maladie genetique cutanee rare et severe de l'enfant, caracterisee par une erythrodermie desquamative congenitale, une dysplasie pilaire specifique et une atopie severe. Notre equipe a identifie le gene dont les mutations sont responsables de la maladie, SPINK5, qui code pour LEKTI, un inhibiteur de protease a serine exprime dans la couche granuleuse de l'epiderme. Afin de mieux comprendre la fonction de LEKTI dans l'homeostasie epidermique, nos travaux ont porte sur la caracterisation structurale et fonctionnelle de LEKTI. Nous avons montre que LEKTI etait produit sous la forme de trois precurseurs rapidement clives par la furine en de nombreux fragments qui presentent des capacites d'inhibition specifiques vis-a-vis des kallikreines epidermiques (KLKs) 5, 7 et 14. Afin de mieux comprendre la physiopathologie du SN, nous avons genere un modele murin Spink5-/-. Les nouveaux-nes KO presentent des erosions cutanees resultant d'une degradation excessive des composants des jonctions intercellulaires due a l'hyperactivite de KLK5 et KLK7. Nous avons identifie par spectrometrie de masse une troisieme protease hyperactive, l'elastase 2 pancreatique (Ela2), dont l'expression epidermique n'etait pas connue. Afin de comprendre son implication specifique dans le developpement du phenotype SN, nous avons genere des souris transgeniques pour Ela2. L'analyse de ces souris revele qu'Ela2 joue un role essentiel dans la formation de la barriere cutanee et est impliquee dans le developpement de nombreux aspects phenotypiques du SN. Ce travail identifie ainsi une nouvelle cible therapeutique potentielle pour le traitement de cette maladie orpheline.