Abnormal deposition of type VII collagen in Kindler syndrome

Diagnostic potential of Type VII Collagen during oral carcinogenesis

Type VII collagen (Col7) is a major component of anchoring fibrils. Col7 plays a role in tumor development and aggressiveness of cutaneous squamous cell carcinoma of recessive dystrophic epidermolysis bullosa. However, the role of Col7 in oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL) remains largely unknown. To elucidate the role of Col7 and its diagnostic potential during oral carcinogenesis. Col7 expression was immunohistochemically studied in 254 samples, including normal oral mucosa (NM), OL without dysplasia, OL with dysplasia, and OSCC. The correlation between Col7 expression and clinicopathologic parameters of OSCC was also determined. Col7 was present as a linear deposit at the basement membrane of NM, OL without dysplasia and OL with dysplasia, and at the tumor-stromal junction around tumor islands in OSCC. Discontinuity of expression was frequently observed in OL with dysplasia and OSCC. OSCC had the significantly lowest Col7 expression (p<0.0001). Compared with OL without dysplasia, OL with dysplasia showed significantly reduced Col7 expression. Patients in clinical stage 4 with positive nodes had low Col7 expression compared with those in clinical stage 1 and negative nodes, respectively. Loss of Col7 is associated with tumorigenesis and aggressiveness in OSCC. A significantly reduced Col7 expression in OSCC implies that Col7 may be a useful marker for diagnosis and therapeutic targets.

Clinical practice guidelines: Oral health care for children and adults living with epidermolysis bullosa

BACKGROUND

Inherited epidermolysis bullosa (EB) is a genetic disorder characterized by skin fragility and unique oral features.

AIMS

To provide (a) a complete review of the oral manifestations in those living with each type of inherited EB, (b) the current best practices for managing oral health care of people living with EB, (c) the current best practices on dental implant-based oral rehabilitation for patients with recessive dystrophic EB (RDEB), and (d) the current best practice for managing local anesthesia, principles of sedation, and general anesthesia for children and adults with EB undergoing dental treatment.

METHODS

Systematic literature search, panel discussion including clinical experts and patient representatives from different centers around the world, external review, and guideline piloting.

RESULTS

This article has been divided into five chapters: (i) general information on EB for the oral health care professional, (ii) systematic literature review on the oral manifestations of EB, (iii) oral health care and dental treatment for children and adults living with EB-clinical practice guidelines, (iv) dental implants in patients with RDEB-clinical practice guidelines, and (v) sedation and anesthesia for adults and children with EB undergoing dental treatment-clinical practice guidelines. Each chapter provides recommendations on the management of the different clinical procedures within dental practice, highlighting the importance of patient-clinician partnership, impact on quality of life, and the importance of follow-up appointments. Guidance on the use on nonadhesive wound care products and emollients to reduce friction during patient care is provided.

CONCLUSIONS

Oral soft and hard tissue manifestations of inherited EB have unique patterns of involvement associated with each subtype of the condition. Understanding each subtype individually will help the professionals plan long-term treatment approaches.

Epidermolysis bullosa and the partnership with autoimmunity: what should we assimilate?

Bullous skin diseases are characterized by genetic abnormalities related to structural epidermal proteins or organ-specific autoantibodies against the same proteins and are revealed by blister formation on skin or mucous membranes, with differences in blister depth, morphology, and topography. Both inherited and autoimmune forms of these disorders can be framed in the context of epidermolysis bullosa. Their clinical spectrum varies from early lethal to mild variants with normal life expectancy, and several distinct phenotypes differ for age of onset, extent, location and depth of skin and mucous lesions, or scarring severity. Recently, different inflammatory processes blended with autoimmune phenomena have been demonstrated in both inherited and acquired epidermolysis bullosa, revealing that this overlapping might cause substantial implications in terms of disease course and outcome. Although several associations between epidermolysis bullosa in its different variants and autoimmune diseases have been reported, it is not yet completely clear how it happens and why this association occurs in only some patients. Autoantibodies are the primary cause of the disease in acquired epidermolysis bullosa, whereas they can be produced as a secondary event due to genetically determined skin damage in inherited epidermolysis bullosa, contributing significantly to the worsening of the disease. The awareness of this overlap may help in identifying new therapeutic approaches with immunosuppressive drugs that could have a significant impact in terms of prognosis.

Dental management of Rothmund-Thomson syndrome with partial anodontia

Rothmund-Thomson syndrome (RTS) is a rare autosomal recessive trait disease. It is characterised by skin, eye and skeletal abnormalities. Abnormalities associated with teeth include abnormal crown and root formations, rudimentary or hypoplastic teeth, microdontia and multiple missing teeth. In the present case, there were multiple decayed primary teeth and multiple congenitally missing permanent teeth. Mandibular left primary first molar (tooth 74) was pulpally involved and obturated with mineral trioxide ggregate. Follow-up after 2 years revealed successful obturation.

Inherited epidermolysis bullosa: clinical and therapeutic aspects

Inherited epidermolysis bullosa (EB) is a heterogeneous group of genetic disorders that present with skin and, in some cases, mucosal fragility, predisposing patients to the development of blisters and/or erosions after minimal trauma or friction. Children with a recurrent history of these kinds of lesions or neonates that present them in the absence of another reasonable explanation should be investigated. Diagnosis must be based on clinical and histopathological findings. To date, management of inherited EB basically consists in avoiding traumas that trigger lesions, as well as preventing infection and facilitating healing of the wounds with the systematic use of bandages.

Partial loss of epithelial phenotype in kindlin-1-deficient keratinocytes

Kindlin-1 is an adaptor protein that is expressed by most epithelial cells and has been implicated in integrin bidirectional signaling. Mutations in the gene encoding kindlin-1 are associated with Kindler syndrome, a recessively inherited disorder that is characterized by fragile skin. Functionally, a loss of kindlin-1 impairs the adhesion of basal keratinocytes to the extracellular matrix both in vivo and in vitro. In this study, we show that the phenotype of mutant keratinocytes deficient in kindlin-1 is characterized by the modification of the cortical actin network and increased plasticity of the plasma membrane. At the molecular level, expression of several proteins associated with an epithelial phenotype, such as α6β4 integrin, collagen XVII, E-cadherin, and desmoglein-3, is strongly reduced, whereas, surprisingly, laminin 332 is synthesized in larger amounts than in control keratinocytes. In contrast, mesenchymal markers such as vimentin and fibronectin are increased in keratinocytes lacking kindlin-1. The switch in cell plasticity and protein expression was confirmed by siRNA-mediated down-regulation of kindlin-1 in HaCaT epithelial cells. Furthermore, there was up-regulation of matrix metalloproteinases and pro-inflammatory cytokines in kindlin-1-deficient keratinocytes. These results provide new insights into the pathogenic mechanisms that take place in Kindler syndrome. Moreover, the constellation of molecular defects associated with the loss of kindlin-1 may explain the higher incidence of skin cancer observed in patients affected with this disorder.

Localization and potential function of kindlin-1 in periodontal tissues

Kindlin-1 is an intracellular focal adhesion protein that regulates the actin cytoskeleton. Patients suffering from Kindler syndrome have a homologous mutation of the kindlin-1 gene and develop skin blisters, periodontal disease, and intestinal complications because of deficient adhesion of the basal epithelial cells. We investigated kindlin-1 localization in periodontal tissue and its functions in cultured keratinocytes and showed that kindlin-1 co-localizes with migfilin and paxillin in the basal epithelial cells of oral mucosa and in cultured keratinocytes. The kindlin-1-deficient oral mucosal tissue from a patient with Kindler syndrome showed a complete lack of paxillin and reduced migfilin immunostaining in the basal keratinocytes. Co-immunoprecipitation showed that migfilin directly interacted with kindlin-1. RNA interference-induced kindlin-1 deficiency in keratinocytes led to an altered distribution of migfilin-containing focal adhesions, reduced cell spreading, decreased cell proliferation, and decelerated cell migration. Disruption of microtubules in the kindlin-1-deficient cells further reduced cell spreading, suggesting that microtubules can partially compensate for kindlin-1 deficiency. Kindlin-1 supported mature cell-extracellular matrix adhesions of keratinocytes, as downregulation of kindlin-1 expression significantly reduced the cell-adhesion strength. In summary, kindlin-1 interacts with migfilin and plays a crucial role in actin-dependent keratinocyte cell adhesion essential for epidermal and periodontal health.

Comparison of cryopreserved and air-dried human amniotic membrane for ophthalmologic applications

BACKGROUND

Cryopreserved amniotic membrane (Cryo-AM) is widely used in ocular surface surgery because of its positive effect on wound healing and its anti-inflammatory properties. A new peracetic acid/ethanol sterilized air-dried amniotic membrane (AD-AM) recently became available which might be an alternative to Cryo-AM. Our aim was to compare AM preserved with both methods with regard to the release of wound-healing modulating proteins, the preservation of basement membrane components, and the ability to serve as a substrate for the cultivation of human limbal epithelial cells (HLECs).

METHODS

Pieces of Cryo-AM and AD-AM from three different donors were incubated in DMEM for five days. The culture supernatant was collected after an incubation period of 0.1, 24, 48, 72 and 120 h; in the case of AD-AM, this period was extended up to 14 days. TIMP-1, IL-1ra, CTGF and TGF-beta1 were detected in the culture supernatant using Western blotting. Twenty human limbal epithelial cultures were initiated on both AD- and Cryo-AM. The cultures were analyzed morphologically, and the outgrowth area was measured in 3-day intervals. Cryosections of Cryo- and AD-AM from three different donors were analyzed histochemically to detect the basement membrane components collagen IV, collagen VII, laminin, laminin 5 and fibronectin.

RESULTS

The release of TIMP-1, IL-1ra and TGF-beta1 from Cryo-AM was constant for the studied period. CTGF showed a stronger signal after 120 h. None of the analyzed proteins, except for a small amount of IL-1ra, could be detected in the supernatant of AD-AM. An outgrowth of HLEC was observed in all cultures on Cryo-AM, but in only 30% of cultures on AD-AM. The outgrowth area on Cryo-AM was at all time points significantly higher than on AD-AM (p < 0.0001). Collagen IV, -VII, laminins and fibronectin were detectable in the basement membrane of Cryo-AM, but only collagen IV and fibronectin in AD-AM.

CONCLUSIONS

Cryo-AM is a more suitable substrate for the cultivation of HLECs than AD-AM. The higher outgrowth rate of cultured limbal epithelium, release of intact soluble wound-healing modulating factors and a better preservation of basement membrane components suggest the superiority of Cryo-AM for use in ophthalmology in comparison to AD-AM.

Kindlins: essential regulators of integrin signalling and cell-matrix adhesion

Integrin-mediated cell-ECM (extracellular matrix) adhesion is a fundamental process that controls cell behaviour. For correct cell-ECM adhesion, both the ligand-binding affinity and the spatial organization of integrins must be precisely controlled; how integrins are regulated, however, is not completely understood. Kindlins constitute a family of evolutionarily conserved cytoplasmic components of cell-ECM adhesions that bind to beta-integrin cytoplasmic tails directly and cooperate with talin in integrin activation. In addition, kindlins interact with many components of cell-ECM adhesions--such as migfilin and integrin-linked kinase--to promote cytoskeletal reorganization. Loss of kindlins causes severe defects in integrin signalling, cell-ECM adhesion and cytoskeletal organization, resulting in early embryonic lethality (kindlin-2), postnatal lethality (kindlin-3) and Kindler syndrome (kindlin-1). It is therefore clear that kindlins, together with several other integrin-proximal proteins, are essential for integrin signalling and cell-ECM adhesion regulation.

Kindler syndrome and periodontal disease: review of the literature and a 12-year follow-up case

BACKGROUND

The association of aggressive periodontitis with Kindler syndrome was based on a single case in 1996 and later confirmed with a larger population. Since then, significant research has greatly increased our understanding of the molecular pathology of this disorder. We review recent advances in the molecular mechanisms of the syndrome and present a maintenance case report of a patient who has been followed in our clinic.

METHODS

A female patient who was diagnosed with Kindler syndrome and aggressive periodontitis at the age of 16 years has been followed and treated in our clinic for 12 years. Her main treatment has been maintenance therapy following her initial treatment and restorative work previously documented. Gingival biopsies obtained during the recent extraction of hopeless maxillary molars were used for histologic assessment of gingival tissue attachment apparatus and to isolate gingival fibroblasts. Reverse transcription-polymerase chain reaction (RT-PCR) was performed using these cells to confirm the lack of expression of kindlin-1.

RESULTS

RT-PCR showed the total loss of kindlin-1 mRNA in cultured gingival fibroblasts, supporting the clinical diagnosis of Kindler syndrome. Tissue biopsies revealed atypical pocket epithelium. Maintenance therapy has been moderately successful. Teeth that were recently lost had a poor prognosis at the initial assessment. The patient's gingiva and oral mucosa continue to be fragile with episodes of sloughing and inflammation.

CONCLUSIONS

Periodontitis in Kindler syndrome responds to maintenance therapy, but the gingiva and oral mucosa continue to display an abnormal appearance with white patches. Histologic findings suggest that the junctional epithelium in Kindler syndrome may be abnormal and could explain why these patients have periodontal disease. Attachment loss progressed around teeth with an initial guarded or poor prognosis. Teeth that started with a good or fair prognosis continue to have a fair prognosis. Limited dental implant treatment is being considered.

Kindler syndrome

Kindler syndrome is a rare, autosomal recessive skin fragility disorder characterized by blistering in infancy, followed by photosensitivity and progressive poikiloderma. Ultrastructural examination reveals marked basement membrane reduplication and variable levels of cleavage at the dermal-epidermal junction. The molecular pathology underlying Kindler syndrome has recently been shown to involve loss-of-function mutations in a novel gene, KIND1, encoding kindlin-1. Immunofluorescence, gene expression and cell biology studies have shown that kindlin-1 is expressed mainly in basal keratinocytes and plays a role in the attachment of the actin cytoskeleton via focal contacts to the extracellular matrix. Thus, Kindler syndrome is the first genodermatosis caused by a defect in actin-extracellular matrix linkage rather than the classic keratin-extracellular matrix linkage underlying the pathology of other inherited skin fragility disorders such as epidermolysis bullosa. This article reviews the clinical features as well as the molecular and cellular pathology of Kindler syndrome and highlights the importance of the new protein, kindlin-1, in cell-matrix adhesion and its intriguing link to photosensitivity.

Characteristic immunohistochemical and ultrastructural findings indicate that Kindler's syndrome is an apoptotic skin disorder

BACKGROUND

Kindler's syndrome is a rare genodermatosis mainly characterized by the onset of skin blistering in early childhood, web formation of fingers and toes, photosensitivity, and progressive poikiloderma. There is still debate whether this disease represents a distinctive entity in the spectrum of congenital bullous poikilodermas or a variant of dystrophic epidermolysis bullosa.

OBJECTIVE

To evaluate the recently proposed and debated characteristic immunohistochemical and ultrastructural features of Kindler's syndrome.

PATIENT/METHODS

Immunofluorescence (IF) antigen mapping and transmission electron microscopy (TEM) were performed on a skin specimen from non-sun-exposed inner aspect of the upper arm of a 49-year-old patient with characteristic clinical features of Kindler's syndrome.

RESULTS

IF studies revealed focally an extensively broadened, partly reticular staining pattern in the dermoepidermal basement membrane zone (BMZ) with antibodies against laminin-5 and type IV as well as type VII collagen. Anti-alpha6 and beta4 integrin staining revealed small gaps in the linear reactivity in the BMZ. Abundant keratin bodies, as detected by anti-immunoglobulin M (IgM) staining, were focally present in the dermis, indicating prominent epidermal apoptosis. This was verified by a histochemical apoptosis stain [terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) reaction]. Transmission electron microscopic examination showed manifold reduplications of the lamina densa (with attached anchoring fibrils) as well as a keratin body surrounded by a fibroblast in the upper dermis.

CONCLUSION

We present characteristic immunohistochemical and ultrastructural features of Kindler's syndrome identical to those described by Shimizu et al. and provide evidence that Kindler's syndrome might primarily be an apoptotic disorder of basal keratinocytes.

Clinical and microbiologic study of periodontitis associated with Kindler syndrome

BACKGROUND

Little is known about the onset and prevalence of periodontal disease in patients with the rare Kindler syndrome, a genodermatological disorder. This study investigated the level of clinical periodontal attachment in relation to age and presence of putative periodontopathogenic bacteria in individuals with Kindler syndrome.

METHODS

Eighteen individuals diagnosed with Kindler syndrome and 13 control subjects, aged 4 to 37 years, from rural Panama received a limited clinical periodontal examination. Subgingival samples were collected for identification of putative periodontal pathogens by polymerase chain reaction.

RESULTS

Mild to severe gingivitis was a common finding in all adults of the study population. Seventy-two percent (13/18) of the Kindler patients and 46% (6/13) of the control subjects showed mild to severe periodontal disease (P = 0.001, chi-square test). The onset of periodontitis was earlier and the progression occurred at a faster rate in the Kindler group. There was a strong correlation (r = 0.83) between the level of attachment loss and age in the Kindler group and a weaker correlation (r = 0.66) in the control group. The appearance of gingival tissues suggested atypical periodontitis with spontaneous bleeding and fragile, often desquamative, gingiva. In periodontitis patients, Porphyromonas gingivallis and Diallster pneumosintes tended to occur more frequently in control individuals compared to those with Kindler syndrome.

CONCLUSIONS

In the Kindler group, periodontitis had an onset in early teenage years and progressed more rapidly compared to non-Kindler individuals of the same geographic and ethnic group. Clinical and microbiological findings suggest atypical periodontitis in Kindler patients. We propose to include Kindler syndrome in the category of medical disorders predisposing to destructive periodontal disease.

Rothmund-Thomson syndrome: a case report

Rothmund-Thomson syndrome (RTS) is an extremely rare genetic disorder characterized by poikilodermatous skin changes, photosensitivity, and an increased risk of developing skin and bone malignancies. In this case report, the dental and periodontal features of RTS in a 16-year-old female patient are presented. The transmission electron microscopy performed on a gingival biopsy specimen showed structural defects of connective tissue. If the unusual ultrastructural findings of this case are confirmed as being consistent with other RTS patients, it is our opinion that this syndrome can be considered among the systemic diseases associated with early-onset periodontitis.

Exclusion of COL7A1 mutation in Kindler syndrome

We describe a patient with Kindler syndrome with an 18-year follow-up who was initially misdiagnosed as suffering from dystrophic epidermolysis bullosa. The patient's skin showed broad reticulate labeling for collagen VII and reduplication of the lamina densa. Screening of this patient's DNA excluded any pathogenic COL7A1 mutations.

Successful periodontal maintenance of a case with Papillon-Lefèvre syndrome: 12-year follow-up and review of the literature

BACKGROUND

Various approaches to treating the periodontal condition associated with Papillon-Lefèvre syndrome have been reported. These include oral hygiene instruction, use of mouthrinses, frequent debridement, multiple antibiotic regimens, periodontal surgery, extraction of hopeless teeth, and extraction of all deciduous teeth. Because Papillon-Lefèvre syndrome is rare, most publications are case reports, and very few document long-term successful treatment of the periodontal condition.

METHODS

In 1986, a 3.5-year-old Indo-Canadian male was diagnosed with Papillon-Lefèvre syndrome and began periodontal treatment. Initial therapy consisted of debridement every 3 weeks, a 0.12% chlorhexidine mouthrinse, 2 regimens of metronidazole, and oral hygiene instruction for his parents. After 10 months it became apparent that the treatment was having little beneficial effect, since the periodontal destruction continued and teeth 51 and 61 exfoliated. At age 4, all remaining deciduous teeth were extracted and complete dentures inserted for the following 2-year edentulous period; then a 3-month maintenance schedule was maintained.

RESULTS

The patient is now 17 years old and all his adult teeth are present with the exception of the third molars. His oral hygiene varies between moderate and good, with his most recent plaque score at 80% effectiveness. There are no probing depths greater than 4 mm, with the exception of the distal of the lower second molars where opercula are present.

CONCLUSIONS

Extraction of all the deciduous teeth followed by a period of edentulousness may partially explain the fact that there has been no recurrent attachment loss in the permanent teeth up to age 17. Other explanations are discussed as part of the literature review of Papillon-Lefèvre syndrome.

A Japanese case of Kindler syndrome

A 25-year-old Japanese woman presented with contracture of the fingers and toes, and difficulty in opening her mouth. Her grandparents are first cousins, but none of the other members of the family are affected. Bulla formation started at birth on areas of the skin that received pressure, and in infancy and early childhood the lesions were limited only to the acral areas. She also had bilateral, incomplete syndactylies involving all web spaces (Fig. 1a). The formation of blisters ceased after the age of 15 years, but a generalized progressive poikiloderma then appeared with accompanying cutaneous atrophy of the skin of the neck, trunk, and extremities (Fig. 1b). The patient experienced mild photosensitivity of the face and neck. At age 18 years, surgical removal of the webbing of all her fingers was performed. Oral examination showed atrophy of the buccal mucosa, and an inability to fully open the mouth. The patient also suffered from poor dentition and easily bleeding gums, but had no symptoms of esophageal dysfunction. Histology of separate biopsy specimens, taken from the poikilodermatous pretibial and trunk skin, showed classical features of poikiloderma, namely epidermal atrophy with flattening of the rete ridges, vacuolization of basal keratinocytes, pigmentary incontinence, and mild dermal perivascularization (Fig. 2a). Interestingly, dyskeratotic cells (Fig. 2b) and eosinophilic rounded bodies (colloid bodies) (Fig. 2c) were frequently found at the basal keratinocyte layer and in the upper dermis, respectively. Pigment was also present in the upper epidermis. To rule out the possibility of a congenital epidermolysis bullosa, ultrastructural and immunofluorescence studies were performed. Ultrastructural studies demonstrated the reduplication of the basal lamina with branching structures within the upper dermis and cleavage between the lamina densa and the cell membrane of the keratinocytes (Fig. 3a). The numbers of associated anchoring fibrils did not seem to be reduced, and colloid bodies and dyskeratotic cells were detected. Immunofluorescence studies with the antibody against type VII collagen (LH 7 : 2) were subsequently carried out. The results showed extensive broad bands with intermittently discontinuous and reticular staining at the dermo-epidermal junction (DEJ) (Fig. 3b), whereas a linear distribution is typically seen in healthy tissue (data not shown). Interestingly, direct immunofluorescence studies revealed intracellular accumulation of immunoglobulin G (IgG), IgM, IgA, and C3 in colloid bodies under the basement membrane (Fig. 3c).