The clinical efficacy and safety of anti-IgE therapy in recessive dystrophic epidermolysis bullosa.

The treatment of recessive dystrophic epidermolysis bullosa (RDEB) remains challenging. Elevated IgE levels have previously been reported in several RDEB patients. In this prospective, single-centre, open intervention study, elevated IgE levels were seen in 11 out of 12 patients with intense pruritus, and the patients with elevated IgE levels received anti-IgE therapy every 4 weeks for at least three cycles. Compared with the baseline, 10 patients with RDEB had good clinical outcomes with enhanced wound healing, a reduction in Birmingham (epidermolysis bullosa) EB severity score by 15%, a reduction in affected body surface area by 23.3%, amelioration of skin inflammation, and an increase in type VII collagen deposition by 13.1-fold. All the patients had a good tolerance to anti-IgE therapy. Furthermore, patients with higher IgE levels tended to have higher disease severity and more favorable clinical outcomes. Our report also suggested the potential role of IgE in the pathogenesis of inflammatory conditions associated with RDEB. (ChiCTR1900021437).

hTERT-Driven Immortalization of RDEB Fibroblast and Keratinocyte Cell Lines Followed by Cre-Mediated Transgene Elimination.

The recessive form of dystrophic epidermolysis bullosa (RDEB) is a crippling disease caused by impairments in the junctions of the dermis and the basement membrane of the epidermis. Using ectopic expression of hTERT/hTERT + BMI-1 in primary cells, we developed expansible cultures of RDEB fibroblasts and keratinocytes. We showed that they display the properties of their founders, including morphology, contraction ability and expression of the respective specific markers including reduced secretion of type VII collagen (C7). The immortalized keratinocytes retained normal stratification in 3D skin equivalents. The comparison of secreted protein patterns from immortalized RDEB and healthy keratinocytes revealed the differences in the contents of the extracellular matrix that were earlier observed specifically for RDEB. We demonstrated the possibility to reverse the genotype of immortalized cells to the state closer to the progenitors by the Cre-dependent hTERT switch off. Increased ß-galactosidase activity and reduced proliferation of fibroblasts were shown after splitting out of transgenes. We anticipate our cell lines to be tractable models for studying RDEB from the level of single-cell changes to the evaluation of 3D skin equivalents. Our approach permits the creation of standardized and expandable models of RDEB that can be compared with the models based on primary cell cultures.

Leg amputation and dystrophic epidermolysis bullosa: A case report with 15 years of follow-up.

OBJECTIVE: Dystrophic epidermolysis bullosa is a rare disease characterized by widespread blistering of the skin and mucous membranes, which may ultimately prompt limb amputation. In this context, the outcome of fitting a prosthesis to a chronically wounded stump is not well known. Our patient's experience (with 15 years of follow-up) should contribute to better knowledge of this topic. CASE REPORT: A 37-year-old man presented with severe dystrophic epidermolysis bullosa. Recurrent skin carcinoma had led to an amputation below the knee. Despite incessant development of blisters on the stump and the need for wound dressing and padding, the patient has been able to walk freely with a prosthesis and a cane. A large number of skin sarcomas were excised over the 15-year period of prosthesis use. Two falls have resulted in limb fractures. A new sarcoma on the stump marked the end of the use of the prosthesis. DISCUSSION: Despite the constant presence of wounds on the stump, amputees with dystrophic epidermolysis bullosa can successfully be fitted with a prosthesis.

Management of inflammatory corneal melt leading to central perforation in children: a retrospective study and review of literature.

PURPOSE: To assess the outcome of early therapeutic penetrating keratoplasty (PKP) for corneal melt leading to perforation in children. METHODS: Case notes of all the consecutive patients presenting with acute corneal perforation that underwent urgent therapeutic PKP between 2000 and 2010 to the practice of one of the authors, both NHS at Great Ormond Street Hospital for Children and private, were retrospectively reviewed. Onset of perforation, underlying cause, medical and surgical treatment, pre- and post-operative visual acuity, graft clarity, length of follow-up, and post-operative complications were recorded. RESULTS: Four eyes of four consecutive patients (mean age of 9.5 years and median 8.5 years, range 4-17 years) were treated for acquired acute onset corneal perforations. There were three females and one male. Etiologies included herpes simplex keratitis secondary to immune recovery disease post bone marrow transplantation, acanthamoeba keratitis, recessive dystrophic epidermolysis bullosa, and blepharokeratoconjunctivitis with acne rosacea. Pre-operative visual acuity ranged from hand movements to 6/150. All the patients had severe anterior chamber inflammation. All eyes improved in visual acuity ranging from 6/9 to 6/18 with clear grafts at last follow-up. There was no recurrence of melt or perforation. Mean follow-up was 67 months (median 44 months). CONCLUSION: PKP during the acute phase together with aggressive medical therapy and close follow-up may achieve good visual outcomes in children with corneal melt with perforation and should be considered. Waiting may sometimes allow the marked inflammatory response seen in children to cause irreversible structural and/or functional damage.

One Novel Frameshift Mutation on Exon 64 of COL7A1 Gene in an Iranian Individual Suffering Recessive Dystrophic Epidermolysis Bullosa.

Recessive dystrophic epidermolysis bullosa (RDEB) is an extremely rare subtype of bullous dermatosis caused by the COL7A1 gene mutation. After genomic DNA extraction from the peripheral blood sample of all subjects (3 pedigree members and 3 unrelated control individuals), COL7A1 gene screening was performed by PCR amplification and direct DNA sequencing of all of the coding exons and flanking intronic regions. Genetic analysis of the COL7A1 gene in an affected individual revealed a novel mutation: c.5493delG (p.K1831Nfs*10) in exon 64 of the COL7A1 gene in homozygous state. This mutation was not discovered in 3 unrelated Iranian control individuals. These data suggest that c.5493delG may influence the phenotype of RDEB. The result of this case report contributes to the expanding database on COL7A1 mutations.

Dystrophic epidermolysis bullosa: pathogenesis and clinical features.

Dystrophic epidermolysis bullosa (DEB) is relatively well understood. Potential therapies are in development. This article describes the pathogenesis and clinical features of DEB. It also describes therapeutic options and the future of molecular therapies.

Recessive dystrophic epidermolysis bullosa caused by COL7A1 hemizygosity and a missense mutation with complex effects on splicing.

Loss-of-function mutations in the gene encoding type VII collagen, COL7A1, are the molecular basis of the blistering skin disorder, recessive dystrophic epidermolysis bullosa (RDEB). COL7A1 maps to a region of the short arm of chromosome 3 that has been found to be deleted in many types of malignancies. We have characterized the first case of a large genomic deletion in chromosome 3p21.31 that removes COL7A1 entirely in an RDEB patient. This interstitial deletion spans 255 to 520 kb and encompasses 9 to 15 genes, but seems to have no pathological consequences other than RDEB. We show that the second, hemizygous allele of COL7A1 in this patient bears a base substitution within exon 94, c.7245G>A. This translates into an amino acid substitution, p.M2415I, and leads to a complex splicing abnormality that allows marginal levels of functional mRNA and protein to be synthesized. We propose that the leakiness of the splicing defect enables the partial rescue of collagen VII deficiency. This is consistent with the diagnosis of the moderately severe form of RDEB in the proband, at variance with the most severe form, RDEB Hallopeau-Siemens, that would arise from complete collagen VII deficiency.

Epidermólisis bulosa distrófica recesiva: caso clínico / Recessive dystrophic epidermolysis bullosa: report of one case

We report a female newborn with a dystrophic epidermolysis bullosa. The diagnosis was made by electron microscopy of a bullous skin lesion. The importance of reaching a specific diagnosis is underscored. Close relatives can therefore be informed and educated about prognosis, etiology and the possibility of having new affected offspring. An accurate diagnosis can be reached through electronic microscopy or modern immunohistochemical techniques. Further complementary information given by conventional histology is required. A complete study is recommended to minimize errors in the intepretation of morphology (Rev MÚd Chile 2004; 132: 614-8).

A homozygous in-frame deletion in the collagenous domain of bullous pemphigoid antigen BP180 (type XVII collagen) causes generalized atrophic benign epidermolysis bullosa.

We report a missplicing event affecting the expression of bullous pemphigoid antigen BP180 (type XVII collagen) in a patient with generalized atrophic benign epidermolysis bullosa (GABEB). The segregation of the mutated allele in the family is consistent with the pathogenic role of the mutation. The homozygous mutation 2441-2A --> G disrupts a splice-site sequence in gene (BPAG2) for BP180 and results in an in-frame exon skipping within the collagenous ectodomain of the protein. The consequent deletion of 9 amino acids in the mutant BP180 is predicted to alter the structure of the homotrimer and is expected to exert a deleterious effect on stability of the protein that would account for the complete absence of immunoreactivity of the proband's skin to antibodies directed against BP180. These findings underscore the importance of structural integrity of the extracellular domain of BP180 for the stability of the protein.

Epidermolysis bullosa pruriginosa.

Epidermolysis bullosa (EB) pruriginosa is a rare clinical subset of dystrophic EB, characterized by marked itching and presence of prurigo-like or lichenoid features. In order to further delineate the phenotype and understand the pathogenesis of this disorder, the clinical, histological and ultrastructural findings of a 19-year-old patient presenting a typical form of EB pruriginosa are described. The prevalence of papular itchy lichenoid lesions, signs of scratching and paucity of blisters at the time of clinical examination may result in incorrect diagnosis and treatment. Microscopic studies of the lesions show the typical findings of dystrophic EB associated with an unusually high density of collagen bundles and absence of elastic fibres in the upper dermis. Itching lichenoid lesions of EB pruriginosa could represent an abnormal dermal reactivity of some patients to their inherited bullous disorder.

Constitutive activation of the collagenase promoter in recessive dystrophic epidermolysis bullosa fibroblasts: role of endogenously activated AP-1.

Recessive dystrophic epidermolysis bullosa (RDEB) is a mutilating disease of the skin characterized by recurrent blistering and erosions that result from compromised integrity of the basement membrane zone. In this study, fibroblasts derived from the skin of RDEB patients were characterized for expression of the major metalloproteinases, particularly interstitial collagenase. Consistent with previous reports on increased collagenase protein levels in fibroblasts from some RDEB patients, we found that steady-state levels of collagenase mRNA were significantly increased in fibroblast strains derived from three of five RDEB patients compared to fibroblasts obtained from normal donors. Stromelysin mRNA was elevated in the same three fibroblast strains, whereas expression of neither the 72- nor the 92-kDa type IV collagenases was different from that of controls. Tissue inhibitor of metalloproteinases was expressed in RDEB fibroblasts at levels similar to those observed in normal fibroblasts. To investigate the mechanism behind the steady-state elevation in collagenase and stromelysin expression, AP-1 expression and activation were studied. Although levels of Jun expression were not different from those seen in normal fibroblasts, AP-1 activity, as assessed by ability to bind to a TPA response element-containing oligonucleotide, was endogenously elevated in RDEB fibroblasts compared to normal fibroblasts. Transfection studies using a plasmid construct containing the collagenase promoter linked to a CAT reporter gene demonstrated that RDEB fibroblasts were able to support active transcription of the promoter compared to normal fibroblasts. These studies support the hypothesis that RDEB fibroblasts contain chronically activated AP-1, and perhaps other transactivating factors, that contribute to the cellular phenotype of collagenase and stromelysin overexpression.

Inherited blistering diseases of the skin.

Inherited epidermolysis bullosa (EB) comprises some 23 different phenotypic disorders which have as common features the presence of mechanically fragile skin and the tendency to develop blisters, erosions, and in some cases, scarring of the skin. While some forms of this disease are relatively mild, other rarer variants may prove to be life-threatening. In the past 15 years, a wealth of new information has elucidated new clinical and laboratory characteristics of specific EB subsets. In this brief review, the most important aspects of inherited EB are summarized to update the practicing pediatrician about the ever-increasing complexities being discovered about this disease.