Lentiviral expression of wild-type LAMA3A restores cell adhesion in airway basal cells from children with epidermolysis bullosa.

The hallmark of epidermolysis bullosa (EB) is fragile attachment of epithelia due to genetic variants in cell adhesion genes. We describe 16 EB patients treated in the ear, nose, and throat department of a tertiary pediatric hospital linked to the United Kingdom's national EB unit between 1992 and 2023. Patients suffered a high degree of morbidity and mortality from laryngotracheal stenosis. Variants in laminin subunit alpha-3 (LAMA3) were found in 10/15 patients where genotype was available. LAMA3 encodes a subunit of the laminin-332 heterotrimeric extracellular matrix protein complex and is expressed by airway epithelial basal stem cells. We investigated the benefit of restoring wild-type LAMA3 expression in primary EB patient-derived basal cell cultures. EB basal cells demonstrated weak adhesion to cell culture substrates, but could otherwise be expanded similarly to non-EB basal cells. In vitro lentiviral overexpression of LAMA3A in EB basal cells enabled them to differentiate in air-liquid interface cultures, producing cilia with normal ciliary beat frequency. Moreover, transduction restored cell adhesion to levels comparable to a non-EB donor culture. These data provide proof of concept for a combined cell and gene therapy approach to treat airway disease in LAMA3-affected EB.

Itch in recessive dystrophic epidermolysis bullosa: findings of PEBLES, a prospective register study.

BACKGROUND: Itch is common and distressing in epidermolysis bullosa (EB) but has not previously been studied in depth in different recessive dystrophic EB (RDEB) subtypes. OBJECTIVES: As part of a prospective register study of the natural history of RDEB we explored features of itch, medications used, and correlation with disease severity and quality of life. METHODS: Fifty individuals with RDEB aged 8 years and above completed the Leuven Itch Scale (LIS) (total 243 reviews over a 7-year period). Data included itch frequency, severity, duration, distress, circumstances, consequences, itch surface area and medications for itch. The iscorEB disease severity score and the validated EB quality of life tool, QOLEB, were compared to LIS domains and analysed by RDEB subtype. RESULTS: Itch was frequent, present in the preceding month in 93% of reviews. Itch severity and distress were significantly greater in severe (RDEB-S) and pruriginosa (RDEB-Pru) subtypes compared to intermediate RDEB (RDEB-I). Itch medications were reported in just over half of reviews including emollients, topical corticosteroids and antihistamines; the proportion of participants not using medication despite frequent pruritus suggests limited efficacy. In inversa RDEB (RDEB-Inv) and RDEB-I, LIS domains correlated with iscorEB and QOLEB. In contrast to previous studies, correlations were lacking in RDEB-S suggesting that global disease burden relatively reduces the contribution of itch. CONCLUSIONS: This comprehensive study of RDEB-associated itch highlights differences between RDEB subtypes, suggests an unmet need for effective treatments and could serve as control data for future clinical trials incorporating itch as an endpoint.

Management of acute sloughing of the esophageal lining in patients with dystrophic epidermolysis bullosa-A series of six pediatric patients.

BACKGROUND: Dystrophic epidermolysis bullosa (DEB) is a subtype of an inherited skin disorder characterized by skin and mucosal fragility due to collagen VII (COL7A1) gene mutations. Esophageal strictures leading to chronic dysphagia and acute episodes are well recognized complications within this subtype. Sloughing of esophageal mucosa and the treatment of this emergency have heretofore received limited attention in the EB literature. METHODS: We retrospectively reviewed the electronic medical records of the patients who had an acute episode of sloughing of the esophageal lining between 2008 and 2021 and extracted the information regarding their clinical presentation and management. RESULTS: Six patients out of 210 with recessive DEB severe (RDEB-S) (n = 4), RDEB intermediate (RDEB-I) (n = 1) and dominant DEB (DDEB) (n = 1) were identified. The mean age at the time of the episode was 2.7 years. All patients had early-onset severe gastroesophageal reflux. Clinically, they presented with a coughing episode (n = 6), hematemesis (n = 6), vomiting (n = 6), and choking (n = 3), followed by coughing up a string like tissue of variable length, part of the esophageal mucosal lining. Four patients recovered with medical management only, two patients required gastrostomy insertions for feeding due to severe persistent dysphagia and one also required a Nissen's fundoplication to manage severe reflux. One patient had aspiration pneumonia. CONCLUSIONS: Sloughing of varying lengths of segments of the esophagus is an emergency. The lining coughed up needs to be cut at the mouth not pulled and the emergency services called immediately for urgent assessment and management. Expert multidisciplinary care is needed to manage this rare but serious condition.

Mapping the burden of severe forms of epidermolysis bullosa - Implications for patient management.

Background: The pathophysiological processes underlying the phenotypic spectrum of severe forms of epidermolysis bullosa (EB) are complex and poorly understood. Objective: To use burden mapping to explore relationships between primary pathomechanisms and secondary clinical manifestations in severe forms of EB (junctional and dystrophic EB [JEB/DEB]) and highlight strengths and weaknesses in evidence regarding the contribution of different pathways. Methods: Literature searches were performed to identify evidence regarding the pathophysiological and clinical aspects of JEB/DEB. Identified publications and clinical experience were used to construct burden maps to visually communicate plausible connections and their relative importance by subtype. Results: Our findings suggest that most of the clinical consequences of JEB/DEB may result from an abnormal state and/or faulty skin remodeling driven by a vicious cycle of delayed wound healing, predominantly mediated through inflammation. The quantity and quality of evidence varies by individual manifestations and disease subtype. Limitations: The burden maps are provisional hypotheses requiring further validation and are limited by the published evidence base and subjectivity in clinical opinion. Conclusions: Delayed wound healing appears to be a key driver of the burden of JEB/DEB. Further studies are warranted to understand the role of inflammatory mediators and accelerated wound healing in patient management.

Biallelic TUFT1 variants cause woolly hair, superficial skin fragility and desmosomal defects.

BACKGROUND: Desmosomes are complex cell junction structures that connect intermediate filaments providing strong cell-to-cell adhesion in tissues exposed to mechanical stress. OBJECTIVES: To identify causal variants in individuals with woolly hair and skin fragility of unknown genetic cause. METHODS: This research was conducted using whole-genome sequencing, whole-exome sequencing, clinical phenotyping, haplotype analysis, single-cell RNA sequencing data analysis, immunofluorescence microscopy and transmission electron microscopy. RESULTS: We identified homozygous predicted loss-of-function tuftelin-1 (TUFT1) variants in nine individuals, from three families, with woolly hair and skin fragility. One donor splice-site variant, c.60+1G>A, was present in two families, while a frameshift variant, p.Gln189Asnfs*49, was found in the third family. Haplotype analysis showed the c.60+1G>A substitution to be a founder variant in the Irish population that likely arose approximately 20 generations ago. Human and mouse single-cell RNA sequencing data showed TUFT1 expression to be enriched in the hair dermal sheath and keratinocytes. TUFT1 expression was highly correlated with genes encoding desmosomal components implicated in diseases with phenotypes that overlap with the cohort presented here. Immunofluorescence showed tuftelin-1 to be mainly localized to the peripheral cell membranes of keratinocytes in normal skin. Skin samples from individuals with TUFT1 variants showed markedly reduced immunoreactivity for tuftelin-1, with a loss of the keratinocyte cell membrane labelling. Light microscopy revealed keratinocyte adhesion, mild hyperkeratosis and areas of superficial peeling. Transmission electron microscopy showed panepidermal acantholysis with widening of intercellular spaces throughout the epidermis and desmosomal detachment through the inner plaques. CONCLUSIONS: Biallelic loss-of-function TUFT1 variants cause a new autosomal recessive skin/hair disorder characterized by woolly hair texture and early-onset skin fragility. Tuftelin-1 has a role in desmosomal integrity and function.

Prevalence of and risk factors for nutritional deficiency and food allergy in a cohort of 21 patients with Netherton syndrome.

BACKGROUND: Netherton syndrome (NS; OMIM: 256500) is a rare autosomal recessively inherited disease due to SPINK5 mutations. Hair and inflammatory skin involvement are variable along with allergies. Morbidity and mortality are high, particularly in infancy. A detailed clinical analysis of a NS patient cohort should broaden the understanding of nutritional challenges and allergic comorbidities. METHODS: In this retrospective monocentric cohort study, medical and dietetic records of pediatric NS patients, presenting between 1999 and 2018, were reviewed. The severity of skin involvement was assessed according to the extent of the body surface area (BSA) affected by erythema. RESULTS: We identified 21 patients with NS (median age 11.6 years). Within the first 6 months of life, requirements for fluid and kcals/protein were high for all patients (average 228 ml/kg/day) and infants had an average of 1.9 feed changes (range 0-4) due to food intolerance. Clinical evidence for IgE-mediated food allergy was present in 84.2% (16/19 children, 2 no data) with a range of 1-12 food allergies per patient. In 75%, more than one food had to be avoided. Specific IgE levels were falsely positive in 38.3% and 8/18 patients (44.4%). One-third (5/15; 6 no data) of patients, all with severe disease, had anaphylactic reactions following ingestion of fish (n = 2), sesame (n = 1), cow's milk (n = 1), and both peanut and egg (n = 1). CONCLUSIONS: Our data emphasize feeding difficulties in children with NS and reveal an unexpectedly higher prevalence of food allergies that gives evidence to the importance of early coordinated multidisciplinary care for overcoming these challenges in NS.

Establishing an appropriate level of vitamin D supplementation in paediatric patients with recessive dystrophic epidermolysis bullosa.

BACKGROUND: Paediatric patients with recessive dystrophic epidermolysis bullosa (RDEB) are at risk of vitamin D deficiency, owing to lack of sunlight from reduced mobility and having large areas of skin being covered with dressings, and to impaired nutritional intake and status. AIM: To establish an appropriate level of vitamin D supplementation in paediatric patients with RDEB. METHODS: Patients with RDEB attending the EB tertiary multidisciplinary team clinic were enrolled. Serum levels of total 25(OH)D were retrospectively recorded for the study period 2012-2018. Data from clinical records on supplements, bone mineral density (BMD) Z scores, compliance, and use of enteral feeds and/or formula were also recorded. RESULTS: In total, 24 patients met the inclusion criteria: 20 with severe RDEB, 3 with RDEB inversa and 1 with intermediate RDEB. Of the 24 patients, 21 (88%) were advised to take a vitamin D3 supplement in line with Department of Health Guidelines (UK), with the remaining 3 patients receiving sufficient intake from formula or enteral feeds. Thirteen of the 24 (54%) had vitamin D deficiency or insufficiency despite advice to supplement; 9 of these 13 (69%) subsequently started or increased the dosage of vitamin D supplements and levels became sufficient (> 50 nmol/L), while the remaining 4 patients (31%) continued to have persistent insufficient levels due to noncompliance with supplements. Reasons for noncompliance were palatability, cost and forgetting to take the tablets. The dose required to maintain sufficient serum levels increased with age, up to 300% of the reference nutrient intake (RNI). CONCLUSION: All patients with RDEB require a supplement or a formula or enteral/sip feed containing vitamin D to maintain sufficient serum vitamin D. The dose required increases with age and can be up to three times higher than the RNI for the normal population. Compliance may improve using a once-weekly loading dose of vitamin D3. Vitamin D deficiency was not solely causative of a low BMD Z score.

Epidermolysis bullosa acquisita: a case series of three paediatric patients.

Epidermolysis bullosa acquisita is a highly uncommon condition in the paediatric population. This article describes three children with this disease, different clinical presentation and management. It also reviews the most relevant articles on this topic.

The epidemiology of epidermolysis bullosa in England and Wales: data from the national epidermolysis bullosa database.

BACKGROUND: The National Health Service (NHS) epidermolysis bullosa (EB) service, established in 2002, offers comprehensive, free care to all patients in England and Wales. OBJECTIVES: To quantify prevalence, incidence and mortality of EB in England and Wales. METHODS: Demographic data for patients in England and Wales were collected on a secure electronic database, prospectively from January 2002 to April 2021 and retrospectively for cases prior to 2002. Vital status was verified using central NHS data. RESULTS: By March 2021, 2594 individuals were registered, of whom 2361 were living, which yielded a prevalence of 34·8 per million of the population for all EB types [EB simplex (EBS) 17 per million, dystrophic EB (DEB) 10·7 per million, junctional EB (JEB) 1 per million and Kindler EB 0·3 per million]. We recorded 1200 babies with EB born since 2002. The average incidence per million live births for EBS, DEB, JEB and Kindler EB was 32·5, 26·1, 8·9 and 0·9, respectively (total incidence for all types of EB was 67·8 per million). Birth rates fell progressively over the 19-year period for JEB-severe (JEB-S) (r = -0·56) and recessive DEB-severe (r = -0·44) and also for milder types of EB. We observed longer survival in JEB-S over the 19-year period (r2 = 0·18) with a median survival of 12·7 months over the past 5 years. CONCLUSIONS: In this study, we provide the first accurate epidemiological data for EB in England and Wales. We believe the observed reduction in birth incidence of severe types of EB reflects an uptake of genetic counselling advice, whereas the reduction in milder types may be due to delayed presentation. A potential small trend towards longer survival of babies with JEB-S may reflect improved multidisciplinary care.

The impact of using a multistrain probiotic supplement on gastrointestinal function in children and adolescents with severe recessive dystrophic epidermolysis bullosa.

BACKGROUND: Children and adolescents with severe recessive dystrophic epidermolysis bullosa (RDEB-S) often have severe constipation in addition to gastrointestinal dysbiosis, due to frequent antibiotic use and reduced oral diet. Constipation is treated with long-term use of high daily doses of macrogol gel (Movicol Paediatric PlainTM or LaxidoTM). Constipation is refractory to increases in fibre and fluids, and impacts severely on quality of life. AIM: To study the initial impact and efficacy of using a multistrain probiotic supplement daily for 12 weeks in patients with RDEB-S. The authors sought to determine the impact of such a supplement on  gastrointestinal symptoms, stool consistency and the use of macrogol gel to treat constipation, as well as understanding patient reaction, palability and ease of use. METHODS: Patients were identified through the epidermolysis bullosa tertiary multidisciplinary team clinic in July 2021. Patients were included if they had a diagnosis of RDEB-S, prescribed at least one sachet of macrogol gel and provided written consent to take part. Patients were provided, proprietary liquid multistrain probiotic supplement (Symprove™) with a high bacterial count, at a dose of 1 mL kg-1 once a day. Each patient completed an anonymous, nine-question, electronic survey to document symptoms and report overall findings at the start and end of a 12-week trial period. RESULTS: Four patients with RDEB-S (two boys and two girls; age range 7-14 years) who met the inclusion criteria were approached to take part. All patients had chronic constipation requiring daily macrogol gel use (range 2-5 sachets per day). Three out of four (75%) completed the 12-week course. At baseline (before supplementation commenced), all three (100%) patients reported poor oral appetite, constipation, flatulence, abdominal bloating and pain, and frequent skin infections requiring oral antibiotics, with two of the three (66%) patients also having nausea. After 12 weeks of supplementation, all three patients (100%) reported a significant improvement in abdominal pain and bloating, nausea, stool consistency, stool frequency, flatulence and increased appetite. Two of the three patients (66%) were able to reduce their macrogol gel usage and the third patient (33%) was able to stop macrogol gel usage altogether during the study period. All three patients said they would choose to continue using the supplement if it was available. CONCLUSION: We have shown in this case series that giving a multistrain probiotic supplement in patients with RDEB-S has the potential to improve stool consistency and reduce or prevent the need for chronic macrogol gel use. Future larger-scale, placebo-controlled trials are needed to confirm these results.

Clinical trial of ABCB5+ mesenchymal stem cells for recessive dystrophic epidermolysis bullosa.

BACKGROUNDRecessive dystrophic epidermolysis bullosa (RDEB) is a rare, devastating, and life-threatening inherited skin fragility disorder that comes about due to a lack of functional type VII collagen, for which no effective therapy exists. ABCB5+ dermal mesenchymal stem cells (ABCB5+ MSCs) possess immunomodulatory, inflammation-dampening, and tissue-healing capacities. In a Col7a1-/- mouse model of RDEB, treatment with ABCB5+ MSCs markedly extended the animals' lifespans.METHODSIn this international, multicentric, single-arm, phase I/IIa clinical trial, 16 patients (aged 4-36 years) enrolled into 4 age cohorts received 3 i.v. infusions of 2 × 106 ABCB5+ MSCs/kg on days 0, 17, and 35. Patients were followed up for 12 weeks regarding efficacy and 12 months regarding safety.RESULTSAt 12 weeks, statistically significant median (IQR) reductions in the Epidermolysis Bullosa Disease Activity and Scarring Index activity (EBDASI activity) score of 13.0% (2.9%-30%; P = 0.049) and the Instrument for Scoring Clinical Outcome of Research for Epidermolysis Bullosa clinician (iscorEB­c) score of 18.2% (1.9%-39.8%; P = 0.037) were observed. Reductions in itch and pain numerical rating scale scores were greatest on day 35, amounting to 37.5% (0.0%-42.9%; P = 0.033) and 25.0% (-8.4% to 46.4%; P = 0.168), respectively. Three adverse events were considered related to the cell product: 1 mild lymphadenopathy and 2 hypersensitivity reactions. The latter 2 were serious but resolved without sequelae shortly after withdrawal of treatment.CONCLUSIONThis trial demonstrates good tolerability, manageable safety, and potential efficacy of i.v. ABCB5+ MSCs as a readily available disease-modifying therapy for RDEB and provides a rationale for further clinical evaluation.TRIAL REGISTRATIONClinicaltrials.gov NCT03529877; EudraCT 2018-001009-98.FUNDINGThe trial was sponsored by RHEACELL GmbH & Co. KG. Contributions by NYF and MHF to this work were supported by the NIH/National Eye Institute (NEI) grants RO1EY025794 and R24EY028767.

The natural history of laryngo-onycho-cutaneous syndrome: A case series of six pediatric patients and literature review.

BACKGROUND/OBJECTIVES: Laryngo-onycho-cutaneous syndrome (LOC) is a rare subtype of junctional epidermolysis bullosa (JEB), featuring aberrant granulation tissue formation in the skin, larynx, and eyes. So far, three mutations including the specific (founder) mutation in exon 39 of LAMA3 (c.151dup) have been identified, but sparse data exists regarding the natural history, the genotype-phenotype correlation, and its differentiation from other JEB types. METHODS: We reviewed our pediatric EB database to identify English children with clinical and genetically diagnosed LOC within the last 15 years. Their demographic, clinical, and laboratory data were examined. We searched three databases for case reports of LOC between January 1986 and November 2020 and extracted clinical and molecular details. RESULTS: We identified 6 LOC patients, all female (mean age 5.4 years). Periungual hypergranulation and skin fragility were the earliest presenting signs (0-3 months), followed by laryngeal stenosis, symblepharon (mean onset 10.7 and 11.8 months, respectively), and dental abnormalities. Five children developed anemia at an average of 19.2 months. We identified 22 published studies in English with 31 cases. CONCLUSIONS: This study delineates the disease course of LOC and highlights the overlap with some forms of JEB. Classical signs/symptoms including anemia appear early in life. Genetic analysis revealed three new LOC-associated variants and underscores the finding that interpretation of skin immunolabeling and molecular diagnostics can be challenging. We provide recommendations on management of this complex syndrome.

Cutaneous Squamous Cell Carcinoma in Epidermolysis Bullosa: a 28-year Retrospective Study.

Epidermolysis bullosa (EB), notably severe recessive dystrophic EB (RDEB-S), is associated with increased risk of aggressive mucocutaneous squamous cell carcinomas, the major cause of mortality in early adulthood. This observational, retrospective case review describes a series of EB patients with cutaneous squamous cell carcinomas over a 28-year period. Forty-four EB patients with squamous cell carcinomas were identified with a total of 221 primary tumours. They comprised: 31 (70%) with RDEB-S, 4 (9%) with other RDEB subtypes, 5 (11.4%) with dominant dystrophic EB, 3 (6.8%) with intermediate junctional EB and 1 (2.3%) with Kindler EB. Squamous cell carcinomas occurred earlier in RDEB-S (median age 29.5 years; age range 13-52 years) than other groups collectively (median age 47.1 years; age range 30-89 years) and most had multiple tumours (mean 5.8; range 1-44). Squamous cell carcinoma-associated mortality was high in RDEB-S (64.5%), with median survival after first squamous cell carcinoma of 2.4 years (range 0.5-12.6 years), significantly lower than previous reports, highlighting the need for early surveillance and better treatments.

Extensive Epidermal Skin Loss Secondary to HSV Type One: Neonatal Management Challenges.

We describe a rare case of a preterm neonate presenting at birth with extensive epidermal skin loss of over 90% due to disseminated herpes simplex virus type one infection. Differential diagnosis included aplasia cutis and epidermolysis bullosa. Serum PCR and mouth swabs confirmed HSV type one, and the patient required three weeks of treatment with intravenous aciclovir, followed by oral aciclovir. We describe the management challenges and give practical solutions applicable to the care of a neonate presenting with widespread skin loss due to any aetiology.

Generation and Clinical Application of Gene-Modified Autologous Epidermal Sheets in Netherton Syndrome: Lessons Learned from a Phase 1 Trial.

Netherton syndrome (NS) is a rare autosomal recessive skin disorder caused by mutations in SPINK5. It is a debilitating condition with notable mortality in the early years of life. There is no curative treatment. We undertook a nonrandomized, open-label, feasibility, and safety study using autologous keratinocytes transduced with a lentiviral vector encoding SPINK5 under the control of the human involucrin promoter. Six NS subjects were recruited, and gene-modified epithelial sheets were successfully generated in three of five subjects. The sheets exhibited expression of correctly sized lympho-epithelial Kazal-type-related inhibitor (LEKTI) protein after modification. One subject was grafted with a 20 cm2 gene-modified graft on the left anterior thigh without any adverse complications and was monitored by serial sampling for 12 months. Recovery within the graft area was compared against an area outside by morphology, proviral copy number and expression of the SPINK5 encoded protein, LEKTI, and its downstream target kallikrein 5, which exhibited transient functional correction. The study confirmed the feasibility of generating lentiviral gene-modified epidermal sheets for inherited skin diseases such as NS, but sustained LEKTI expression is likely to require the identification, targeting, and engraftment of long-lived keratinocyte stem cell populations for durable therapeutic effects. Important learning points for the application of gene-modified epidermal sheets are discussed.

Oleogel-S10 Phase 3 study "EASE" for epidermolysis bullosa: study design and rationale.

BACKGROUND: Epidermolysis bullosa (EB) is a group of rare, genetic diseases that affect the integrity of epithelial tissues, most notably the skin. Patients experience recurrent skin wounding, with severity depending on type, sub-type, and mutation. Oleogel-S10, a formulation of birch bark extract, has demonstrated efficacy in a Phase 2 trial assessing re-epithelialization of wounds in EB. EASE (NCT03068780, EudraCT 2016-002066-32) is a randomized, Phase 3, placebo-controlled study designed to determine the efficacy of Oleogel-S10 versus placebo in patients with EB. METHODS: EASE is a Phase 3, two-phase study comprising a 90-day, double-blind, randomized, placebo-controlled phase, followed by 24 months of open-label, single-arm follow-up. Patients with junctional EB, dystrophic EB, or Kindler syndrome and target wounds (10 - 50cm2) present for > 21 days and < 9 months, are randomized in a 1:1 ratio to receive wound dressings according to local standard of care with or without Oleogel-S10. Placebo is based on the Oleogel-S10 vehicle, which is sunflower oil formulated to have a consistency indistinguishable from that of the active product. The primary endpoint of the trial, directed by the US health authority according to the required study endpoints for chronic cutaneous ulcer and burn wounds, is to compare the efficacy of Oleogel-S10 versus placebo according to the proportion of patients with complete closure of the target wound within 45 ± 7 days of treatment. Additional EB-focused endpoints include wound burden, patient-reported outcomes, and safety. RESULTS: Results of the primary endpoint are anticipated to be available by H2 2019. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03068780 . EudraCT, 2016-002066-32. Registered on 3 March 2017.