Epidermolysis bullosa (EB) comprises a collection of clinically diverse inherited blistering diseases that affect the skin and, in some subtypes, mucous membranes and other organs. Currently classified into four main subtypes (EB simplex, junctional EB, dystrophic EB, and Kindler syndrome, mainly based on the level of skin cleavage), the spectrum of EB extends to more than 30 clinical subtypes with pathogenic mutations in at least 18 distinct genes. This review focuses on three recent additions to variants of EB: all are autosomal recessive, and result from mutations in either DST-e (coding for epidermal dystonin, also known as the 230 kDa bullous pemphigoid antigen, BP230), EXPH5 (coding for exophilin-5, also known as Slac2-b), or ITGA3 (coding for the integrin alpha-3 subunit). Each of these new forms of EB is reviewed with respect to the initial gene discovery, clinical features, the current mutation database, and skin pathology. Awareness of these recently described forms of EB is helpful in the clinical evaluation of patients with EB and in defining genotype-phenotype correlation for inherited blistering skin diseases.
Basement Membrane ; Blister ; Epidermolysis Bullosa* ; Genetic Association Studies ; Hemidesmosomes ; Humans ; Mucous Membrane ; Pathology ; Pemphigoid, Bullous ; Skin ; Skin Diseases ; Transport Vesicles

PURPOSE: To investigate the effects of an amniotic membrane patch on corneal epithelial thickness and formation of hemidesmosomes during corneal stromal wound healing. METHODS: A stromal wound 9 mm in diameter and 130 microm in depth was created on rabbit cornea using a microkeratome. The changes in corneal epithelial thickness and hemidesmosome formations were compared between the amniotic membrane, contact lens, and control groups. Changes in the corneal epithelium were examined using H&E staining and hemidesmosome formation was examined using an electron microscope at 2 and 4 weeks after flap removal. RESULTS: Two weeks after treatment, the corneal epithelial thickness was 95.3 +/- 6.3 microm in the amniotic membrane group being significantly thicker than 76.4 +/- 5.1 microm in the contact lens group and 68.3 +/- 6.1 microm in the control group. Furthermore, more hemidesmosome formations were observed in the amniotic membrane group compared to the other 2 groups. However, there were no significant differences in corneal epithelial thickness or hemidesmosome formation among the 3 groups at week 4. CONCLUSIONS: The amniotic membrane group showed a thicker corneal epithelium and more hemidesmosome formation than the other 2 groups 2 weeks after flap removal. Thus, the use of an amniotic membrane patch appears to be effective in the early stages of corneal stromal wound healing.
Amnion ; Cornea ; Electrons ; Epithelium, Corneal ; Hemidesmosomes ; Wound Healing

BACKGROUND: Matrix metalloproteinases (MMPs) participate in extracellular matrix degradation and may play an important role in basal membrane damage in many dermatologic diseases. Recent studies implicated the importance of MMP-9 in the pathogenesis of bulla formation of bullous pemphigoid (BP). Various autoimmune bullous diseases are strongly associated with desmosome or hemidesmosome pathologies, and show an increased level of lesional MMP and exposed autoantigens from these structures. OBJECTIVE: This study evaluated the level of MMP-2, -3, and -9 in three types of autoimmune bullous disease [BP, pemphigus vulgaris (PV), pemphigus foliaceus (PF)] with the aim of investigating the role of MMPs in the pathogenesis of autoimmune bullous diseases. METHODS: Sample specimens were obtained from skin lesions of patients with BP (n=12), PV (n=10), and PF (n=12), and from normal controls (n=8). The immunohistochemical expression of MMP-2, -3, and -9 was analyzed and serum levels of MMP-2, -3, and -9 were measured by enzyme-linked immunosorbant assay (ELISA). The results were analyzed with reference to graded levels of clinical severity. RESULTS: Expression of dermal MMP-2, -3, and -9 were increased in BP, PV, and PF (p=0.036, 0.022, and 0.015, respectively). However, decreased expression of the three MMPs in the epidermis of skin lesions may have resulted from epidermal destruction. ELISA-determined serum levels of MMP-2, -3, and -9 increased in BP, PV and PF. Interestingly, MMP-2 was significantly increased in the sera of BP patients (p=0.015), consistent with the previous studies concerning the role of gelatinase (MMP-2 and -9) in the pathogenesis of BP. In BP patients, clinical severity was proportional to increased levels of MMP-2 in both skin lesions and and sera. CONCLUSION: The increased expression of MMP-2, -3, and -9 in skin lesions and sera may reflect the involvement of these enzymes in the mechanism of bulla formation in autoimmune bullous diseases including BP. In addition, expression of MMP and clinical severity may be closely connected.
Autoantigens ; Blister ; Desmosomes ; Epidermis ; Extracellular Matrix ; Gelatinases ; Hemidesmosomes ; Humans ; Matrix Metalloproteinases ; Membranes ; Pemphigoid, Bullous ; Pemphigus ; Skin

The importance of soft tissue response to implant abutments has become one of the major issues in current implant dentistry. To date, numerous studies have emphasized on maintaining connective tissue barriers in quantity, as well as in quality for the long term success of dental implants. The cells mainly consisting the soft tissue around dental implants are fibroblasts and epithelial cells. The mechanism of the fibroblasts'adhesions to certain substrata can be explained by the 'focal adhesion'theory. On the other hand, epithelial cells adhere to the substratum via hemidesmosomes. The typical integrin-mediated adhesions of cells to certain matrix are called 'cell-matrix adhsions'. The focal adhesion complex of fibroblasts, in relation to the cell-matrix adhsions, consists of the extracellular matrix(ECM) such as fibronectin, the transmembrane proteins such as integrins, the intracellular cytoplasmic proteins such as vinculin, talin, and more, and the cytoskeletal structures such as filamentous actin and microtubules. The mechanosensory function of integrins and focal adhesion complexes are considered to play a major role in the cells'adhesion, migration, proliferation, differentiation, division, and even apoptosis. The '3-D matrix adhesions'defined by Cukierman et al. makes a promising future for the verification of the actual process of the cell-matrix adhesions in vivo and can be applied to the field of implant dentistry in relation to obtaining strong soft tissue attachment to the implant abutments.
Actins ; Apoptosis ; Cell-Matrix Junctions* ; Connective Tissue ; Cytoplasm ; Dental Implants* ; Dentistry ; Epithelial Cells ; Fibroblasts ; Fibronectins ; Focal Adhesions ; Hand ; Hemidesmosomes ; Integrins ; Microtubules ; Talin ; Vinculin

The importance of soft tissue response to implant abutments has become one of the major issues in current implant dentistry. To date, numerous studies have emphasized on maintaining connective tissue barriers in quantity, as well as in quality for the long term success of dental implants. The cells mainly consisting the soft tissue around dental implants are fibroblasts and epithelial cells. The mechanism of the fibroblasts'adhesions to certain substrata can be explained by the 'focal adhesion'theory. On the other hand, epithelial cells adhere to the substratum via hemidesmosomes. The typical integrin-mediated adhesions of cells to certain matrix are called 'cell-matrix adhsions'. The focal adhesion complex of fibroblasts, in relation to the cell-matrix adhsions, consists of the extracellular matrix(ECM) such as fibronectin, the transmembrane proteins such as integrins, the intracellular cytoplasmic proteins such as vinculin, talin, and more, and the cytoskeletal structures such as filamentous actin and microtubules. The mechanosensory function of integrins and focal adhesion complexes are considered to play a major role in the cells'adhesion, migration, proliferation, differentiation, division, and even apoptosis. The '3-D matrix adhesions'defined by Cukierman et al. makes a promising future for the verification of the actual process of the cell-matrix adhesions in vivo and can be applied to the field of implant dentistry in relation to obtaining strong soft tissue attachment to the implant abutments.
Actins ; Apoptosis ; Cell-Matrix Junctions* ; Connective Tissue ; Cytoplasm ; Dental Implants* ; Dentistry ; Epithelial Cells ; Fibroblasts ; Fibronectins ; Focal Adhesions ; Hand ; Hemidesmosomes ; Integrins ; Microtubules ; Talin ; Vinculin

Acellular Dermis ; Basement Membrane ; Cell Division ; Epithelial Cells ; Feeder Cells ; Fibroblasts ; Hand ; Hemidesmosomes ; Humans ; Keratin-14 ; Keratinocytes ; Mouth Mucosa ; Mucous Membrane ; Rabbits ; Tolonium Chloride

PURPOSE: To evaluate the changes in corneal fine structure of diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats, compared with age-matched nondiabetic rats. METHODS: At the ages of 30 and 50 weeks, we measured the body weight and blood glucose level of OELTF and control rats (n=5 in each age-matched group). Using the transmission electron micrography (TEM), we examined the ultrastructural changes between the corneas of 30-and 50-week-old OLETF and control rats. RESULTS: At the age of 30 and 50 weeks, the mean body weight and blood glucose levels of OLETF rats were significantly higher than those of control rats (p<0.05). The area of basement membrane occupied by hemidesmosome decreased significantly in OLETF rats at the ages of 30 and 50 weeks compared with control rats (p<0.001). In TEM, the corneas of OLETF rats showed irregular, thick basement membranes thin hemidesmosomes and decreased anchoring fibrils formation, compared with control rats. There was no significant difference of Descemet's membrane thickness between OLETF and control rats (p>0.05). CONCLUSIONS: The author could observe the changes of the corneal adherent complex and basement membrane in OLETF rats, a new strain of spontaneous non-insulin dependent diabetes mellitus (NIDDM) model. OLETF rats may be useful as an animal model of NIDDM to examine the diabetic corneal changes.
Animals ; Basement Membrane ; Blood Glucose ; Body Weight ; Cornea* ; Descemet Membrane ; Diabetes Mellitus ; Diabetes Mellitus, Type 2 ; Hemidesmosomes ; Models, Animal ; Rats* ; Rats, Inbred OLETF

PURPOSE: To investigate adhesion complex formation in cultivated human limbal epithelium after transplantation into the chemical burn model. METHODS: human limbal epithelial cells were cultured on amniotic membrane that had not undergone dispase treatment. Laminin V was evaluated using immunohistochemistry. The adhesion complex was examined by electron microscopy. Cultured epithelium was transplanted into limbal deficient rabbits induced by chemical burn and mechanical limbal removal. The transplanted rabbits and the controls with mechanical wounding were sacrificed at 1, 2, 3, and 4 weeks. The adhesion complex was examined by electron microscopy. RESULTS: Linear staining was observed against laminin V at 4-week culture but matured adhesion complex was not found. Graft failure developed in 3 rabbits (25%) after transplantation. Morphologically identifiable hemidesmosomes appeared at 1 week and matured adhesion complex with continuous basement membrane was found at 3 weeks. The mean numbers of hemidesmosomes/2.25 micro meter were 2.3 +/- 0.9, 2.5 +/- 0.5, 5.2 +/- 1.0, and 4.0 +/- 0.9 at 1, 2, 3, and 4 weeks, respectively. The adhesion assembly nearly recovered to the level of that in the human cornea (3.7 +/- 60.11) at 3 weeks. CONCLUSIONS: Adhesion complex of cultivated limbal epithelium did not developed in vitro, but the assembly was almost completed at 3 weeks after transplantation in vivo.
Amnion* ; Basement Membrane ; Burns, Chemical* ; Cornea ; Epithelial Cells ; Epithelium* ; Hemidesmosomes ; Humans ; Immunohistochemistry ; Laminin ; Microscopy, Electron ; Rabbits ; Transplants ; Wounds and Injuries

PURPOSE: Recently, 20% ethanol has been used to make a corneal epithelial flap effectively. We investigated the toxicity of ethanol using the corneal epithelial cell line and rat cornea. METHODS: Cultured corneal epithelial cells were exposed to different concentrations (5~60%) of ethanol for different exposure time (20~120 seconds). And then cell viability was measured with MTT assay. In vivo, rat central corneas (3mm in diameter) were exposed to 20% ethanol for 30 seconds. The eyes were enucleated, fixed and processed for light microscopy (LM) and transmission electron microscopy (TEM) at indicated interval (0, 4, 8 and 12hours, 1, 3 and 7 days). TUNEL assay was used to detect apoptotic cells. RESULTS: Cultured epithelial cells showed survival rate of over 50% in ethanol concentration of below 20% (76.2 +/- 7.4%) and exposure time of below 1 minute (54.8 +/- 6.5%). In vivo experiment, after 20% ethanol exposure for 30 seconds, vacuoles were detected in the nuclei of epithelial cells and gradually disappeared. Hemidesmosomes were detected in the basement membrane at all times. TUNEL positive cells were detected in the epithelial layer and anterior stroma at the edge until 8hrs. CONCLUSIONS: Our results showed 20% ethanol exposure for 30 seconds did not seems to induce significant damage to the cornea. Corneal epithelial damage could occur by physical force during epithelial flap making.
Animals ; Basement Membrane ; Cell Survival ; Cornea* ; Epithelial Cells ; Ethanol* ; Hemidesmosomes ; In Situ Nick-End Labeling ; Keratectomy, Subepithelial, Laser-Assisted* ; Microscopy ; Microscopy, Electron, Transmission ; Rats ; Survival Rate ; Vacuoles

PURPOSE: In LASEK models, the viability of corneal epithelial cells after ethanol treatment was investigated in addition to morphological analysis. METHODS: Cell viability was assayed using a confocal laser scanning microscopy(CLSM) and MTT assay for in vivo and cultured rabbit corneal epithelial cells after treatment with various concentrations of ethanol. Ethanol treated human corneas were compared with control in terms of structural changes. RESULTS: CLSM assay showed that cells were viable at the ratio of 78.5, 75.0, 57.3, 43.3, 23.9, 4.3% for 0, 10, 20, 30 40, 60 % ethanol groups, respectively. The relative survival rates in comparison to 0% ethanol-treated (control) corneas were 95.5(10%), 72.9(20%), 55.2(30%), 30.4(40%), 5.5(60%). On MTT assay after 10, 20, 25, 30, 40, 60% ethanol treatment, cultured epithelial cells were still alive at the percentage of 92.7, 92.2, 36.6, 30.7, 5.4, 5.1% (20 sec), 90.8, 57.1, 29.0. 28.6, 5.0, 4.7% (40 sec) at 0 hr with decreasing cell survival over time in 20% ethanol group. TEM showed multiple vacuole-like loosenings along the intercellular junction of superficial squamous and wing cells. The loss and break-up of hemidesmosome and basement membrane were also demonstrated in conjunction with the loosening of sub-basal interface. CONCLUSIONS: After 20% ethanol exposure for 40 seconds, 72.9% and 57.1% of in vivo and cultured rabbit corneal epithelial cells were in viable state with decreasing cell survival over increasing ethanol concentration and time. The loss and break-up of hemidesmosome and basement membrane, resulting in loosening of sub-basal interface, might be the mechanism for the detachment of LASEK flap en bloc.
Basement Membrane ; Cell Survival ; Cornea ; Epithelial Cells* ; Epithelium, Corneal ; Ethanol* ; Hemidesmosomes ; Humans ; Intercellular Junctions ; Keratectomy, Subepithelial, Laser-Assisted ; Survival Rate