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1.
Kalinin is an extracellular adhesion molecule specific to epithelial basement membranes (BM) identified as a component of anchoring filaments of hemidesmosomes. This heterotrimeric protein is synthesized by cultured normal human keratinocytes and is involved in cell attachment. In indirect immunofluorescence studies, the epidermal BM of patients with junctional epidermolysis bullosa (JEB) of Herlitz's type were found not to be reactive with the anti-kalinin monoclonal antibodies ka146 and K140 and displayed a decreased immunoreactivity to two anti-kalinin antibodies cross-reacting with K-laminin, an anchoring filament component recently described. The intrinsic defect of JEB keratinocytes in the synthesis of kalinin was further documented by indirect immunofluorescence on in vitro cultures of these cells. In non-Herlitz JEB patients, staining of BM was constantly detected. Impairment of expression of kalinin correlated with the lack of reactivity to the monoclonal antibody GB3, which detects the BM component nicein/BM600. These results clearly demonstrate a defect of kalinin expression in epithelial basement membranes of Herlitz JEB patients and suggest that kalinin may play a role in the pathogenesis of the disease. Further studies are in progress to define possible relationships between kalinin and nicein.  相似文献   

2.
Hemidesmosomes are frequently rudimentary in junctional epidermolysis bullosa (JEB), and JEB keratinocytes display abnormal attachment to the substrate in culture. Our aim was to determine whether this abnormality reflects defective hemidesmosome synthesis in vitro. Keratinocytes from five JEB patients were cultured under standard conditions. Control cultures, from four healthy males, three patients with dystrophic EB (DEB), and one patient with the simplex variant (EBS), were also examined. Post-confluent cultures were processed for transmission electron microscopy. Hemidesmosome-like structures were counted in electron micrograph montages. The number of hemidesmosome-like structures in JEB cultures (0.97 +/- 0.57, per 10 microns of basal cell membrane) was approximately 17% of the value for normal controls (5.81 +/- 3.08, P less than 0.02). The values for EBS (3.72) and DEB (3.28 +/- 1.44) were not statistically different from normal controls. In addition hemidesmosome-like structures in JEB cultures were morphologically ill-defined, compared with those from controls. This correlated with the loose apposition between JEB keratinocytes and the substrate, which appeared tight in controls. JEB keratinocytes continue to express in vitro a major phenotypic abnormality which characterizes the disease in vivo. Therefore, this model should prove useful in studies determining the pathogenesis and possible new treatments of JEB.  相似文献   

3.
The integrin alpha 6 beta 4 is a member of the integrin family of adhesion receptors. The integrin alpha 6 beta 4 is preferentially expressed in stratified squamous epithelia, where it is localized in hemidesmosomes. A reduced number of rudimentary hemidesmosomes is often found in skin from patients with junctional epidermolysis bullosa (JEB). In this study we have investigated the expression of alpha 6 beta 4 in skin specimens of patients with junctional (one non-lethal, two lethal) and dystrophic (two) epidermolysis bullosa, using immunofluorescent (IF) staining with five different monoclonal antibodies against the alpha 6 and beta 4 subunits. The intensity of IF staining of the integrin alpha 6 beta 4 and bullous pemphigoid antigen (BPA) was unreduced along the epidermal basement membrane zone (EBMZ) of all EB patients, compared to that in skin of healthy human controls. However, in the skin of two patients with lethal (Herlitz) JEB, who did not express GB3, IF staining of integrin alpha 6 beta 4 and BPA showed a "stitchy" discontinuous linear pattern along the EBMZ with interruptions at the borders of adjoining basal keratinocytes. The same results were obtained by immunoelectron microscopy. They corresponded with freeze-induced partial cell detachment from the basement membrane at the ultimate baso-lateral edge of the basal keratinocytes in lethal JEB skin. The basal lamellipodia at that location almost completely lacked tonofilaments and hemidesmosomes. Furthermore, in JEB there was a split between the intra- and extracellular epitopes of the integrin alpha 6 beta 4 receptor, whereas the integrin remains intact in salt-split skin. This suggests that the defect is in alpha 6 beta 4 itself or perhaps its ligand.  相似文献   

4.
Kindler-Syndrom     
The Kindler syndrome is a new form of inherited epidermolysis bullosa and the first genodermatosis caused by a defect of the focal adhesions. Kindlin-1, the deficient protein, plays an essential role in integrin activation and in the adhesion of keratinocytes to the extracellular matrix. The adhesion defect leads to skin blistering which begins at birth and ameliorates with age, and to mucosal fragility which leads to scarring and stricture formation. Skin atrophy and poikiloderma develop progressively. Photosensitivity is rather mild, but squamous cell carcinomas develop on sun-exposed areas mainly after the age of 40 years. The most important differential diagnoses are epidermolysis bullosa with mottled pigmentation and dystrophic epidermolysis bullosa. Management aims to treat the symptoms and prevent complications.  相似文献   

5.
泛发性萎缩性良性大疱性表皮松解症我国首例报道   总被引:3,自引:1,他引:2  
目的 报道我国首例泛发性萎缩性良性大疱性表皮松解症家系。方法 对该家系先证者的临床资料、组织病理、透射电镜、间接免疫荧光检查进行分析。结果 该患者除了先天性大疱性表皮松解症的症状外,特征性表现是萎缩性秃发和牙齿发育不良。透射电镜检查裂隙位于基底膜透明板,同时伴半桥粒数目减少和发育不良。间接免疫荧光检查发现患者针对大疱性类天疱疮抗原2的荧光消失,说明本例发病与编码大疱性类天疱疮抗原2的基因COL17A1的缺陷有关。结论 此例为泛发性萎缩性良性大疱性表皮松解症,是交界性大疱性表皮松解症的一种特殊亚型。泛发性萎缩性良性大疱性表皮松解症有一定的临床特点,透射电镜和间接免疫荧光检查对于正确诊断和分型十分重要,并对进一步基因突变位点研究有指导作用。  相似文献   

6.
Background  Replacing mutant skin in epidermolysis bullosa (EB) by epithelial sheets of transduced autologous keratinocytes is the essential surgical step of ex vivo gene therapy. The same applies for revertant cell therapy in which epithelial sheets of revertant autologous keratinocytes are used. Revertant cells can be found in patches of normal skin in patients with junctional EB (JEB) due to revertant mosaicism caused by in vivo reversions.
Objectives  To develop a technique of adhesive tape stripping as a method for epidermis removal to prepare the acceptor site for revertant cell therapy in a patient with revertant mosaic JEB.
Methods  We performed revertant cell therapy on a patient with mosaic type XVII collagen-deficient non-Herlitz JEB. Skin biopsies were taken from revertant skin on the wrist. Graft production took place on a 3T3-J2 feeder layer resulting in two 6 × 7 cm grafts. An innovative method that uses the pathological plane of least resistance of JEB skin was developed to prepare the acceptor site. A polyacrylate adhesive plaster was placed on the skin and then pulled off with the epidermis.
Results  The epidermis was easily removed with the plaster. The skin separated at the level of the lamina lucida, leaving a bloodless wound bed of naked lamina densa. Transplantation was successful; the acceptor site healed without scarring. However, blistering could be provoked. The functional repair was not achieved due to the low percentage of revertant cells in the graft.
Conclusions  We conclude that adhesive stripping is a simple, effective and almost painless procedure for removing epidermis for ex vivo cell therapy in EB.  相似文献   

7.
Laminin 5 (kalinin/epiligrin/nicein) is an essential structural component of the dermal-epidermal junction, composed of three polypeptide subunits: laminin alpha3, beta3 and gamma2. Studies of the inherited skin fragility disorder junctional epidermolysis bullosa (JEB) have suggested that the major role of this heterotrimeric protein is to act as an adhesive ligand essential for binding the epidermis to the underlying dermis and thus maintaining the integrity of the skin. Protein interaction studies have shown that the C terminus of the alpha3 subunit binds to a range of integrin complexes depending on the motility status of keratinocytes. This allows laminin 5 to interact with either hemidesmosomes or the actin cytoskeleton. Recently we have reported that the absence of the N-terminal region of laminin alpha3a in laryngo-onchyo-cutaneous syndrome causes excessive granulation tissue production at wound sites. As granulation tissue production is also a problem in JEB, this implicates laminin 5 in control of this wound healing response.  相似文献   

8.
9.
We report a 4-year-old female mongrel dog with a history since birth of erosions and atrophic skin, with pigmentation and alopecia on the face, trunk and extremities, together with dystrophic nails. Light microscopy revealed subepidermal blisters with minimal inflammation and electron microscopy confirmed that the ultrastructural site of separation site was at the lamina lucida. Indirect immunofluorescence of the dog's skin detected the positive expression of laminin 5. BPAG2, integrinα6 and type VII collagen. These clinical, ultrastructural and immunohistochemical features suggested that the dog had a non-lethal subtype of junctional epidermolysis bullosa (JEB). This is the first confirmed case of non-lethal JEB in a dog and presents a possible candidate for an animal model of gene therapy. Further study should provide important information of the phenotype, pathophysiology and prognosis of non-lethal JEB in humans.  相似文献   

10.
先天性大疱性表皮松解症基底膜带分子的研究   总被引:2,自引:0,他引:2  
目的:通过透射电镜和免疫荧光研究先天性大疱性表皮松解症患者的基底膜带分子。方法:分析7个组织病理表现为表皮下疱的先天性大疱性表皮松解症患者的透射电镜和免疫荧光表现。结果:电镜检查1例为基底膜透明板裂隙,即JEB,其余6例为基底膜下裂隙,即DEB,间接免疫荧光检查此例JEB是BPAG2缺陷。结合临床资料诊断为泛发型萎缩性良性大疱性表皮松解症(generalized atrophic benign EB,GABEB),这是我国首例报告;6例DEB患者透射电镜和免疫荧光检查辅助诊断DDEB和RDEB。结论:先天性大疱性表皮松解症是一组疾病,电镜和免疫荧光检查对于分型和明确诊断是必需的,间接免疫荧光检查还可以指导进一步的基因诊断。  相似文献   

11.
Junctional epidermolysis bullosa and pyloric atresia in two siblings   总被引:1,自引:0,他引:1  
Pyloric atresia is a rare disorder that has been seen in association with epidermolysis bullosa. Two male siblings with pyloric atresia and the junctional form of epidermolysis bullosa, confirmed by electron microscopy, are described herein. These cases strengthen the relationship between junctional epidermolysis bullosa and pyloric atresia, which are probably transmitted together in an autosomal-recessive pattern.  相似文献   

12.
Junctional epidermolysis bullosa (JEB) is a clinically and genetically heterogeneous recessively inherited blistering disease of the skin and mucous membranes due to impaired epithelial adhesion. In particular, defective expression of the 180-kD bullous pemphigoid antigen (BP180) has been correlated to a non-lethal (non-Herlitz) form of JEB, generalized atrophic benign epidermolysis bullosa (GABEB), characterized by widespread skin blistering healing with atrophy and by atrophic alopecia with onset in childhood. We report the case of a 33-year-old man suffering from a generalized blistering skin disorder since birth. He also presented nail dystrophy and tooth abnormalities. Mucosal involvement was limited to gingival erosion. Alopecia was absent and body, axillary and pubic hair were normal. Immunofluorescence analysis showed a markedly reduced expression of BP180, electron microscopy studies evidenced hypoplastic hemidesmosomes and Northern blot analysis confirmed a striking decrease in the amount of BP180 mRNA. The clinical features of our patient confirm that BP180 deficiency usually results in a non-Herlitz JEB form. However, the degree of skin, mucous membranes and hair involvement appears more variable and less typical than originally described for GABEB.  相似文献   

13.
Mutations in ITGB4 are known to cause autosomal recessive junctional epidermolysis bullosa (JEB), which is manifested by severe blistering and granulation tissue, usually complicating pyloric atresia and even leading to death. ITGB4-associated autosomal dominant epidermolysis bullosa has rarely been documented. Herein, we identified a heterozygous pathogenic variant (c.433G>T; p.Asp145Tyr) in ITGB4 causing a mild phenotype of JEB in a Chinese family.  相似文献   

14.
Prenatal diagnosis of recessive dystrophic epidermolysis bullosa was successfully achieved at 19 weeks' gestation by indirect immunofluorescence examination of a fetal skin biopsy sample using the monoclonal antibody LH 7:2. The abortus displayed marked blistering and the diagnosis was confirmed by transmission electron microscopy (TEM). In 3 further pregnancies at risk for lethal junctional epidermolysis bullosa the diagnosis was excluded using the polyclonal antibody AA3. In all these studies the results were available within 4 h of receiving the samples. These new techniques offer a quick and simple alternative to TEM for midtrimester prenatal diagnosis of 2 severe recessive forms of epidermolysis bullosa.  相似文献   

15.
A 22-year-old woman, whose first infant had died of lethal junctional epidermolysis bullosa (JEB), requested prenatal diagnosis for her third pregnancy. At 20 weeks gestation, fetal biopsy was performed under direct vision by fetoscopy. A semithin section of epon-embedded skin showed dermo-epidermal separation at the light microscopic level. Electron microscopy revealed the site of separation to be within the lamina lucida of the epidermal basement membrane (EBM). Indirect immunofluorescence on a 5 microns cryostat specimen of skin showed a complete absence of GB3 monoclonal antibody immunostaining at the EBM compared with a control 18 week old normal fetal skin sample. The diagnosis was therefore made that the fetus was affected with lethal JEB and a prostaglandin termination performed. The diagnosis was confirmed by further studies on the aborted fetus. 54 cases of prenatal diagnosis of various types of epidermolysis bullosa performed at Institute of Dermatology over the last 10 years are briefly reviewed. Several social and practical problems to launch prenatal diagnosis in Japan are also discussed.  相似文献   

16.
The classification of mechanobullous diseases often depends on the electron microscopic distinction of intradermal (dermolytic), junctional and intraepidermal sites of cleavage. Electron microscopy is tedious and time consuming. In this report we describe a different approach to the determination of the cleavage plane by using a method which recognizes subtle differences in the localization of antigenic structures relative to the cleavage plane. Cryostat sections of lesional and extralesional skin of 3 patients with dermolytic epidermolysis bullosa, 3 with epidermolytic epidermolysis bullosa and 8 with junctional epidermolysis bullosa were examined by immunofluorescence, with specific antisera against type IV collagen (localized within the basal lamina); against laminin (noncollagenous protein, localized in the lamina lucida); and with bullous pemphigoid antibodies (directed against the bullous pemphigoid antigen localized in the lamina lucida). All specimens were also examined by electron microscopy. In dermolytic epidermolysis bullosa (where cleft formation occurs intradermally) type IV collagen, laminin and the bullous pemphigoid antigen were consistently found in the roof of the blister, whereas in junctional epidermolysis bullosa (where the cleft occurs in the lamina lucida) type IV collagen and laminin were found on the floor of the blister whereas bullous pemphigoid antigen was present mainly on the roof, but focally also on the floor, of the blister. In epidermolytic epidermolysis bullosa (where the cleft is intraepidermal) all antigens were localized below the cleavage plane. In all cases electron microscopy confirmed the level of cleft formation predicted from the immunofluorescence mapping of the antigenic sites. The described method equals electron microscopy in accuracy but it is more rapid and simpler to perform.  相似文献   

17.
Summary Distinctive abnormality in the organization of keratin intermediate filaments (KIFs) was found for the first time in cultured epidermal keratinocytes from two patients with hereditary epidermolysis bullosa simplex (EBS), which showed cleavages above the basement membrane zone due to the fragility of basal cells. KIFs in EBS keratinocytes revealed an irregular radial arrangement composed of sparse but thick KIF bundles. Furthermore, these KIF bundles in many cells changed into numerous ball-like keratin aggregates and disappeared beyond these keratin aggregates in the peripheral cytoplasm. Electron microscopy of cultured EBS keratinocytes showed that many ball-like structures consisting of fine filaments or granules or homogeneous substances were scattered in the peripheral regions of the cell attaching to the dish, and intermediate filaments appeared to be emanating from or surrounding the structures. These ball-like keratin aggregates have never been observed in normal human keratinocytes.  相似文献   

18.
Abstract: We report an infant with Herlitz junctional epidermolysis bullosa (JEB) presenting at birth with erosions on the scalp, thigh, and periumbilical area in addition to nail abnormalities. Ultrastructural studies demonstrated a split through the lamina lucida with poorly formed hemidesmosomes and no clearly defined subbasal dense plates. Indirect immunofluorescence staining with antibodies GB3 (antiiaminin 5) and 19-DEJ-1 (antiuncein) was totally absent. These findings, in combination with the clinical picture, favor a diagnosis of Herlitz JEB, Immunohistochemistry findings greatly facilitated an accurate diagnosis, which is essential in view of the poor prognosis for patients with this form of junctional epidermoiysis bullosa.  相似文献   

19.
Junctional epidermolysis bullosa (JEB) is an inherited mechanobullous disease characterized by reduced adherence of the epidermal keratinocytes to the underlying dermis, and is often caused by the absence of functional laminin 332 due to the lack or dysfunction of its beta3 chain. As there are no specific therapies for JEB, we tested whether a protein replacement strategy could be applicable for the restoration of the laminin 332 assembly and reversion of the JEB phenotype in human keratinocytes that lack beta3 subunit. Here, we developed the protocol for production and purification of the biologically active recombinant beta3 chain. Next, we demonstrated that delivery of recombinant beta3 polypeptide into the endoplasmic reticulum of the immortalized beta3-null keratinocytes led to the restoration of the laminin 332 assembly, secretion, and deposition into the basement membrane zone, as confirmed by Western blot analysis, confocal immunofluorescent microscopy in vitro, and on cultured organotypic human JEB skin reconstructs. Although the amount of laminin 332 produced by protein-treated beta3-null keratinocytes is lower than that in normal human keratinocytes, our results demonstrate the applicability of the recombinant proteins for JEB treatment and open new perspectives for the development of novel therapeutics for this inherited, currently intractable, skin disorder.  相似文献   

20.
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