Combinatorial Omics Analysis Reveals Perturbed Lysosomal Homeostasis in Collagen VII-deficient Keratinocytes.

The extracellular matrix protein collagen VII is part of the microenvironment of stratified epithelia and critical in organismal homeostasis. Mutations in the encoding gene COL7A1 lead to the skin disorder dystrophic epidermolysis bullosa (DEB), are linked to skin fragility and progressive inflammation-driven fibrosis that facilitates aggressive skin cancer. So far, these changes have been linked to mesenchymal alterations, the epithelial consequences of collagen VII loss remaining under-addressed. As epithelial dysfunction is a principal initiator of fibrosis, we performed a comprehensive transcriptome and proteome profiling of primary human keratinocytes from DEB and control subjects to generate global and detailed images of dysregulated epidermal molecular pathways linked to loss of collagen VII. These revealed downregulation of interaction partners of collagen VII on mRNA and protein level, but also increased abundance of S100 pro-inflammatory proteins in primary DEB keratinocytes. Increased TGF-ß signaling because of loss of collagen VII was associated with enhanced activity of lysosomal proteases in both keratinocytes and skin of collagen VII-deficient individuals. Thus, loss of a single structural protein, collagen VII, has extra- and intracellular consequences, resulting in inflammatory processes that enable tissue destabilization and promote keratinocyte-driven, progressive fibrosis.

Health and Productivity Benefits with Early Intensified Treatment in Patients with Type 2 Diabetes: Results from Korea.

The available evidence suggests positive health outcomes associated with early treatment intensification in Type 2 diabetes mellitus (T2DM). Our study estimated the productivity effects arising from improved health correlated with early intensified treatment in T2DM in Korea. Using a recently published methodology and model, we investigated the association between early intensified treatment and the probability of experiencing fewer diabetes-related complication events. Treatment strategies leading to better health outcomes are expected to be associated with social value through increased participation in paid and unpaid work activities. Therefore, we translated the lower incidence of complications into monetary terms related to productivity for the Korean population. We quantified productivity by considering (a) absenteeism, (b) presenteeism, (c) permanent loss of labor force, and (d) activity restriction. Deterministic and probabilistic sensitivity analyses in the base case parameter were performed. Approximately, 1.7 thousand (standard deviation [SD] ±580 events) micro- and macrovascular complication events could potentially be avoided by early treatment intensification. This led to a societal gain attributed to increased productivity of 23 million USD (SD ± $8.2 million). This article demonstrates the likelihood of achieving better health and productivity through early intensified treatment in diabetes.

Plectin Deficiency in Fibroblasts Deranges Intermediate Filament and Organelle Morphology, Migration, and Adhesion.

Plectin, a highly versatile and multifunctional cytolinker, has been implicated in several multisystemic disorders. Most sequence variations in the human plectin gene (PLEC) cause epidermolysis bullosa simplex with muscular dystrophy (EBS-MD), an autosomal recessive skin-blistering disorder associated with progressive muscle weakness. In this study, we performed a comprehensive cell biological analysis of dermal fibroblasts from three different patients with EBS-MD, where PLEC expression analyses revealed preserved mRNA levels in all cases, whereas full-length plectin protein content was significantly reduced or completely absent. Downstream effects of pathogenic PLEC sequence alterations included massive bundling of vimentin intermediate filament networks, including the occurrence of ring-like nuclei-encasing filament bundles, elongated mitochondrial networks, and abnormal nuclear morphologies. We found that essential fibroblast functions such as wound healing, migration, or orientation upon cyclic stretch were significantly impaired in the cells of patients with EBS-MD. Finally, EBS-MD fibroblasts displayed reduced adhesion capacities, which could be attributed to smaller focal adhesion contacts. Our study not only emphasizes plectin's functional role in human skin fibroblasts, it also provides further insights into the understanding of EBS-MD-associated disease mechanisms.

Case Report: Diagnostic and Therapeutic Challenges in Severe Mechanobullous Epidermolysis Bullosa Acquisita.

Collagen VII is the main constituent of the anchoring fibrils, important adhesive structures that attach the epidermis to the dermal extracellular matrix. Two disorders are caused by dysfunction of collagen VII, both characterized by skin and mucosa fragility, epidermolysis bullosa acquisita (EBA) and dystrophic epidermolysis bullosa (DEB). EBA and DEB share high clinical similarities with significant difference in patients' age of onset and pathogenesis. Our patients presented with severe and recalcitrant mechanobullous EBA with characteristic DIF, IIF and ELISA diagnostics. But in both women recessive COL7A1 variants were also found, in a monoallelic state. Collagen VII from EBA keratinocytes of our cases was significantly more vulnerable to proteolytic degradation than control keratinocytes, hinting that the heterozygous pathogenic variants were sufficient to destabilize the molecule in vitro. Thus, even if the amount and functionality of mutant and normal type VII collagen polypeptides is sufficient to assure dermal-epidermal adhesion in healthy individuals, the functionally-impaired proteins are probably more prone to development of autoantibodies against them. Our work suggests that testing for COL7A1 genetic variants should be considered in patients with EBA, which either have a patient history hinting towards underlying dystrophic epidermolysis bullosa or pose therapeutic challenges.

QR-313, an Antisense Oligonucleotide, Shows Therapeutic Efficacy for Treatment of Dominant and Recessive Dystrophic Epidermolysis Bullosa: A Preclinical Study.

Dystrophic epidermolysis bullosa (DEB) is a blistering skin disease caused by mutations in the gene COL7A1 encoding collagen VII. DEB can be inherited as recessive DEB (RDEB) or dominant DEB (DDEB) and is associated with a high wound burden. Perpetual cycles of wounding and healing drive fibrosis in DDEB and RDEB, as well as the formation of a tumor-permissive microenvironment. Prolonging wound-free episodes by improving the quality of wound healing would therefore confer substantial benefit for individuals with DEB. The collagenous domain of collagen VII is encoded by 82 in-frame exons, which makes splice-modulation therapies attractive for DEB. Indeed, antisense oligonucleotide-based exon skipping has shown promise for RDEB. However, the suitability of antisense oligonucleotides for treatment of DDEB remains unexplored. Here, we developed QR-313, a clinically applicable, potent antisense oligonucleotide specifically targeting exon 73. We show the feasibility of topical delivery of QR-313 in a carbomer-composed gel for treatment of wounds to restore collagen VII abundance in human RDEB skin. Our data reveal that QR-313 also shows direct benefit for DDEB caused by exon 73 mutations. Thus, the same topically applied therapeutic could be used to improve the wound healing quality in RDEB and DDEB.

Proteomic Profiling of Fibroblasts Isolated from Chronic Wounds Identifies Disease-Relevant Signaling Pathways.

Chronic skin wounds accompany many prevalent age-related diseases and are a major cause of morbidity and mortality. Both keratinocytes and fibroblasts contribute to the pathomechanisms in chronic skin wounds. Dysregulated pathways in the epidermis have been extensively studied, but little is known of the influence of dermal fibroblasts on chronic wounding. We isolated fibroblasts from chronic wounds, propagated them in vitro, and analyzed them using proteomic profiling in combination with functional characterization of the proteomic changes. Chronic wound-associated fibroblasts exhibit a unique proteome profile characteristic of lysosomal dysfunction and dysregulated TGFß signaling. They display a decreased propensity for cell proliferation and migration, combined with an enhanced ability to contract the extracellular matrix. With these properties, chronic wound-associated fibroblasts actively contribute to pathological inabilities to close wounds and represent potential targets for pharmacological interference for changing cellular phenotypes.

Treatment of keratinocytes with 4-phenylbutyrate in epidermolysis bullosa: Lessons for therapies in keratin disorders.

BACKGROUND: Missense mutations in keratin 5 and 14 genes cause the severe skin fragility disorder epidermolysis bullosa simplex (EBS) by collapsing of the keratin cytoskeleton into cytoplasmic protein aggregates. Despite intense efforts, no molecular therapies are available, mostly due to the complex phenotype of EBS, comprising cell fragility, diminished adhesion, skin inflammation and itch. METHODS: We extensively characterized KRT5 and KRT14 mutant keratinocytes from patients with severe generalized EBS following exposure to the chemical chaperone 4-phenylbutyrate (4-PBA). FINDINGS: 4-PBA diminished keratin aggregates within EBS cells and ameliorated their inflammatory phenotype. Chemoproteomics of 4-PBA-treated and untreated EBS cells revealed reduced IL1ß expression- but also showed activation of Wnt/ß-catenin and NF-kB pathways. The abundance of extracellular matrix and cytoskeletal proteins was significantly altered, coinciding with diminished keratinocyte adhesion and migration in a 4-PBA dose-dependent manner. INTERPRETATION: Together, our study reveals a complex interplay of benefits and disadvantages that challenge the use of 4-PBA in skin fragility disorders.

Postpartum thrombotic microangiopathy revealed as atypical hemolytic uremic syndrome successfully treated with eculizumab: a case report.

INTRODUCTION: Differential diagnosis of thrombotic microangiopathies can be difficult. Atypical hemolytic uremic syndrome is a rare, life-threatening disease caused by uncontrolled chronic activation of alternative complement pathway, resulting in microvascular thrombosis, organ ischemia and damage. Prognosis is poor: up to 65 percent of patients require dialysis or have kidney damage of varying severity or die despite plasma exchange/plasma infusion treatment. CASE PRESENTATION: We describe the case of a 23-year-old woman of Hellenic origin who, after a preeclampsia-induced premature delivery, developed thrombotic microangiopathy with renal failure, tonicoclonic seizures, anasarca edema and hypertension. Intensive plasma exchange was initiated twice daily, in parallel to dialysis for one month. Three months later, our patient was discharged with nondialysis-dependent renal failure and without signs of hemolysis. Three months after discharge our patient was readmitted with cardiomyopathy (left ventricular ejection fraction of 25 percent) and signs and symptoms of thrombotic microangiopathy. Our patient was diagnosed with atypical hemolytic uremic syndrome and was started on eculizumab (a complement inhibitor), which improved clinical and laboratory parameters. However, a transient pause in treatment resulted in thrombotic microangiopathy relapse, which was rapidly blocked with reintroduction of eculizumab treatment. During long-term eculizumab treatment, thrombotic microangiopathy manifestations were inhibited and renal and cardiac function restored, with no need for other invasive treatments. CONCLUSIONS: Establishing the diagnosis of atypical hemolytic uremic syndrome in patients presenting with thrombotic microangiopathy is challenging since common symptoms are shared with other conditions like Shiga toxin-producing Escherichia coli hemolytic uremic syndrome and thrombotic thrombocytopenic purpura. The described case illustrates the complexity and importance of rapid diagnosis in a rare disease and the need for appropriate and specific treatment for best long-term outcomes.