Surface Of Keratinocytes Research Articles

CD9 regulates keratinocyte migration by negatively modulating the sheddase activity of ADAM17.

CD9 is a trans-membrane protein, and has recently been implicated in different physiological and cellular processes, such as cell migration and adhesion. According to previous study, down-regulation of CD9 contributes to keratinocyte migration, critical for wound re-epithelialization. Nevertheless, it is widely believed that tetraspanin CD9 does not have ligands or function as the cell surface receptor, rather it is thought to associate with other transmembrane molecules, thereby mediate keratinocyte migration. Little is known about how CD9 associates with transmembrane molecules in migratory keratinocytes. Here, using confocal microscopy, we observed that tetraspanin CD9 and ADAM17 co-localized on the surface of keratinocytes in the course of wound repair in vivo and in vitro. Co-immunoprecipitation experiments demonstrated a direct association between CD9 and ADAM17 in HaCaT cells and C57-MKs. Functional studies revealed that down-regulation or over-expression of CD9 exerted negative regulatory effects on ADAM17 sheddase activity. This activity is involved in CD9-regulated cell motility and migration. Further studies found that ADAM17 inhibitor-TAPI-2 or siADAM17 significantly abolished the enhanced effect of keratinocyte migration induced by CD9 down-regulation. Meanwhile, the sheddase activity of ADAM17 was inhibited by TAPI-2, which decreased this release of AREG and HB-EGF in CD9-silenced HaCat cells and C57-MKs. Importantly, neutralizing antibody against HB-EGF significant weakened keratinocyte migration and motility in CD9-silenced keratinocytes, and the inhibition of CD9-regulated keratinocyte migration by siADAM17 was rescued by addition of recombinant HB-EGF, activating EGFR/ERK pathway. Collectively, our results suggest that ADAM17 sheddase activity is activated by down-regulation of CD9, thereby mediating shedding of HB-EGF and activation of EGFR/ERK signaling, which crucially affects the keratinocyte migration and wound healing.

Sustained release of recombinant thrombomodulin from cross-linked gelatin/hyaluronic acid hydrogels potentiate wound healing in diabetic mice

Thrombomodulin (TM) is a type-I transmembrane glycoprotein expressed on the surfaces of endothelial cells and epidermal keratinocytes. It is known to regulate blood coagulation, inflammation, and cell-cell adhesion. A recombinant TM, which contains an epidermal growth factor-like domain and serine/threonine-riches domain, has been demonstrated to stimulate cell proliferation and migration of keratinocytes and wound healing. In this study, we developed the biodegradable hydrogels and evaluated the efficacy of sustained release of rhTM from the hydrogel for the treatment of diabetic wounds. The hydrogels were composed of gelatin with or without hyaluronic acid, and fabricated by chemical cross-linking followed by lyophilization. Gelatin-based hydrogels had porous structure, good swelling property, and were biodegradable with characteristics of slow rhTM release in a short term. The once every-3-day rhTM-loaded hydrogel (with hyaluronic acid) markedly promoted wound healing and were superior to rhTM solution, once daily rhTM hydrogel (without hyaluronic acid), hydrogel controls, and once every-3-day rhEGF hydrogel treatment groups. The rhTM hydrogels enhanced granulation tissue formation, re-epithelialization, collagen deposition, and angiogenesis in wound repair. The once every-3-day rhTM hydrogel was stable and drug release was maintained up to 11-month of storage at 4 °C. The developed rhTM hydrogels could meet the needs for clinical practice, and may have future medical applications for wound care in diabetic patients.

Regenerative potential of partially differentiated mesenchymal stromal cells in a mouse model of a full-thickness skin wound.

Mesenchymal stromal cells (MSCs, known as mesenchymal stem cells) are considered to be a promising therapeutic tool for many diseases. But it is still unclear which cells are more efficient and safe for wound healing and tissue regeneration for clinical applications: undifferentiated, partially differentiated stem cells or differentiated cells. In this study, we modified MSCs with keratinocyte-conditioned medium (KCM) and examined MSCs, partially differentiated MSCs (PMSCs) and differentiated cell migration, accumulation in the wounded area as well as cell regenerative efficiency in a full-thickness skin wound model. In addition to that, the impact of intradermal and intravenous cell delivery methods of wound healing was evaluated. C57BL/6J mouse compact bone MSCs were treated with a KCM for 14 days. Flow cytometry analysis showed the appearance of keratinocyte surface markers which were absent in MSCs, whereas the specific markers for MSCs were lost. Cells were injected either intravenously or intradermally in C57BL/6J mice. Wound closure, cell migration and accumulation in the wounded area were further analysed. Wound healing was assessed by the rate of wound closure and by histological evaluation. Cells were monitored using optical imaging. We demonstrated that PMSCs showed morphology similar to keratinocyte cells, had enhanced migration and increased survival at the site of injury. PMSCs had a beneficial effect on wound healing and tissue regeneration. This effect was reinforced when these cells were injected intravenously. Due to their partial differentiation status, we assume that PMSCs can differentiate more rapidly into epidermal cell lineages thus causing faster and qualitatively improved wound healing.

Inhibition of Human Papillomavirus Type 16 Infection Using an RNA Aptamer.

Human papillomavirus type 16 (HPV16) DNA has been found in ∼50% of cervical tumors worldwide. HPV infection starts with the binding of the virus capsid to heparan sulfate (HS) receptors exposed on the surface of epithelial basal layer keratinocytes. Previously, our group isolated a high-affinity RNA aptamer (Sc5c3) specific for HPV16 L1 virus-like particles (VLPs). In this study, we report the inhibition of HPV16 infection by Sc5c3 in a pseudovirus (PsVs) model. 293TT cells were infected by HPV16 PsVs containing the yellow fluorescent protein (YFP) as reporter gene. Incubation of HPV16 PsVs with Sc5c3 before infection resulted in a dose-dependent decrease in YFP fluorescence, suggesting infection inhibition. Aptamer degradation by RNase A restored PsVs infectivity, supporting the previous observation that Sc5c3 aptamer can inhibit infection. VLP mutants with removed HS binding sites were used in binding assays to elucidate the Sc5c3 blocking mechanism; however, no binding difference was observed between wild-type and mutant VLPs, suggesting that pseudoinfection inhibition relies on mechanisms additional to electrostatic HS binding site interaction. A DNA/RNA Sc5c3 version also inhibited HPV PsVs infection, suggesting that a modified, nuclease-resistant Sc5c3 may be used to inhibit HPV16 infection in vivo.

Computational model of wound healing: EGF secreted by fibroblasts promotes delayed re-epithelialization of epithelial keratinocytes.

It is widely agreed that keratinocyte migration plays a crucial role in wound re-epithelialization. Defects in this function contribute to wound reoccurrence causing significant clinical problems. Several in vitro studies have shown that the speed of migrating keratinocytes can be regulated by epidermal growth factor (EGF) which affects keratinocyte's integrin expression. The relationship between integrin expression (through cell-matrix adhesion) stimulated by EGF and keratinocyte migration speed is not linear since increased adhesion, due to increased integrin expression, has been experimentally shown to slow down cell migration due to the biphasic dependence of cell speed on adhesion. In our previous work we showed that keratinocytes that were co-cultured with EGF-enhanced fibroblasts formed an asymmetric migration pattern, where, the cumulative distances of keratinocytes migrating toward fibroblasts were smaller than those migrating away from fibroblasts. This asymmetric pattern is thought to be provoked by high EGF concentration secreted by fibroblasts. The EGF stimulates the expression of integrin receptors on the surface of keratinocytes migrating toward fibroblasts via paracrine signaling. In this paper, we present a computational model of keratinocyte migration that is controlled by EGF secreted by fibroblasts using the Cellular Potts Model (CPM). Our computational simulation results confirm the asymmetric pattern observed in experiments. These results provide a deeper insight into our understanding of the complexity of keratinocyte migration in the presence of growth factor gradients and may explain re-epithelialization failure in impaired wound healing.

An unusual case of pemphigus erythematosus

Pemphigus erythematosus is characterized by fragile vesicles or bullae, erosions, crusts, and scales in seborrheic area. There are several forms of atypical lesions such as erythematous papules and plaques, verrucous plaques, pustules, and lichenification. Here, we report an atypical pemphigus erythematosus with erythematous papules, plaques, and pustules skin lesions. A 52-year-old Indonesian man presented with prominent pruritic erythematous macules, papules, plaques on the scalp, trunk, and extremities, and also a pustule for each on the back and right arm. Clinically, the patient was diagnosed as small-plaque parapsoriasis, but histopathology examination on the pustule revealed a subcorneal acantholysis and direct immunofluorescence staining showed immunoglobulin G and complement C3 on the cell surface of keratinocytes. These result suitable for pemphigus erythematosus. The patient was treated with topical and systemic corticosteroid, and there were significant improvements in the skin lesions. Pemphigus erythematosus may present with prominent erythematous papules, plaques, and a few pustules. A careful assessment of the clinical manifestation and histopathological findings enabled us to make a correct diagnosis and succesfully treat the patient.

Pénfigo Vulgar y Lupus Eritematoso Sistémico. Reporte de caso

El Lupus Eritematoso sistémico (LES) es una enfermedad autoinmunitaria, multisistémica y episódica, caracterizada por la inflamación vascular generalizada y del tejido conectivo, además por la presencia de anticuerpos antinucleares (ANA) y anticuerpos anti-DNA de doble cadena. El término pénfigo; enfermedad ampollar poco frecuente, de etiología autoinmune, que afecta la piel y mucosas. Define un grupo de enfermedades autoinmunes de la piel caracterizadas por la presencia de inmunoglobulina G (IgG) dirigida a la superficie de los queratinocitos y ampollas debidas a acantólisis (separación intercelular). Paciente femenina de 16 años de edad, con historia de presentar edema en rodilla derecha, manos y pies acompañada de artralgias de un año de evolución. Además, dificultad para la deambulación de 3 días de evolución. Presentó lesiones ampollosas en mucosa oral y labio superior confluyentes y se extienden a piel circundante. Las articulaciones metacarpofalángicas de manos estaban edematizadas, dolorosas, con leve deformidad y limitación funcional. Lasampollas inicialmente localizadas en cara y extremidades inferiores se fueron extendiendo a miembros inferiores, acompañado de eritema palmar bilateral. Se le diagnosticó Pénfigo Vulgar y Lupus Eritematoso Sistémico. Este último, por presentar criterios laboratoriales compatibles con LES: leucopenia, ANA positivo, nefropatía y artritis. Se inició tratamiento con prednisona 50 mg vía oral cada día (1 mg/kg/día). Palabras clave Enfermedades Autoinmunes, Lupus Eritematoso Sistémico, Péngo

Comparison of Direct Immunofluorescence of Plucked Hair and Skin for Evaluation of Immunological Remission in Pemphigus.

Background:Pemphigus is a chronic autoimmune bullous disorder characterized by autoantibodies directed against desmoglein 3 and/or 1. Demonstration of intercellular deposition of IgG on the cell surface of keratinocytes by direct immunofluorescence (DIF) of the skin is the gold standard in the diagnosis of pemphigus. Recently, DIF of plucked hair demonstrating intercellular deposition of IgG in the outer root sheath (ORS) has shown to be useful.Objective:To compare the DIF of plucked hair and skin for the evaluation of immunological remission in pemphigus vulgaris patients in clinical remission.Materials and Methods:A total of 30 patients with pemphigus vulgaris with positive DIF of the skin and hair at baseline were included, and DIF of skin and hair was repeated after 6 months or more of clinical remission (with no new/non-healing lesions). Presence of intercellular deposits of IgG and or C3 in skin and ORS of the hair was considered as positive.Results:Of the 30 patients, DIF of skin was positive in 10 patients and hair was positive 14 patients. The findings of hair and skin DIF correlated with each other in 22 patients. In 6 (20%) patients DIF of hair was positive even though the DIF of skin was negative. The sensitivity of hair DIF was 80% and specificity was 70%.Limitations:Small sample size.Conclusion:DIF of hair is a simple, non-invasive, and cost effective procedure and can be used as an additional procedure for the assessment of immunological remission in patients with pemphigus vulgaris.

Non-pathogenic pemphigus foliaceus (PF) IgG acts synergistically with a directly pathogenic PF IgG to increase blistering by p38MAPK-dependent desmoglein 1 clustering

BackgroundPemphigus foliaceus (PF) is an autoimmune blistering disease caused by autoantibodies (Abs) against desmoglein 1 (Dsg1). PF sera contain polyclonal Abs which are heterogeneous mixture of both pathogenic and non-pathogenic Abs, as shown by isolation of monoclonal Abs (mAbs). ObjectiveTo investigate how pathogenic and non-pathogenic anti-Dsg1 Abs contribute to blister formation in PF. MethodsUsing organ-cultured human skin, we compared the effect of a single pathogenic anti-Dsg1 IgG mAb, a single non-pathogenic anti-Dsg1 IgG mAb, and their mixture on blister formation as analyzed by histology, subcellular localization of IgG deposits and desmosomal proteins by confocal microscopy, and desmosomal structure by electron microscopy. In addition, we measured keratinocyte adhesion by an in vitro dissociation assay. Results24h after injection, a single pathogenic anti-Dsg1 IgG caused a subcorneal blister with IgG and Dsg1 localized linearly on the cell surface of keratinocytes. A single non-pathogenic anti-Dsg1 IgG bound linearly on the keratinocytes but did not induce blisters. A pathogenic and a non-pathogenic IgG mAb injected together caused an aberrant granular pattern of IgG and Dsg1 in the lower epidermis with blister formation in the superficial epidermis. Electron microscopy demonstrated that the mixture of mAbs shortened desmosomal lengths more than a single mAb in the basal and spinous layers. Furthermore, although Dsg1 clustering required both cross-linking of Dsg1 molecules by the non-pathogenic IgG plus a pathogenic antibody, the latter could be in the form of a monovalent single chain variable fragment, suggesting that loss of trans-interaction of Dsg1 is required for clustering. Finally, a p38MAPK inhibitor blocked Dsg1 clustering. When pathogenic strength was measured by the dissociation assay, a mixture of pathogenic and non-pathogenic IgG mAbs disrupted keratinocyte adhesion more than a single pathogenic mAb. This pathogenic effect was only partially suppressed by the p38MAPK inhibitor. ConclusionThese findings indicate that a polyclonal mixture of anti-Dsg1 IgG antibodies enhances pathogenic activity for blister formation associated with p38MAPK-dependent Dsg1 clustering and that not only pathogenic antibodies but also non-pathogenic antibodies coordinately contribute to blister formation in PF.

Pemphigus foliaceous associated with Herpes simplex virus infection

Pemphigus is a group of autoimmune blistering diseases of the skin and/or mucous membranes caused by the presence of antibodies against adhesion molecules on the cell surface of keratinocytes.[1] Most cases are localized to the face and trunk and are characterized by recurrent crops of flaccid bullae that readily rupture, resulting in shallow crusted erosions which heal leaving behind hyperpigmentation. Rarely can it also present as erythroderma.[2] Management requires immunosuppressive therapy.

Uterine natural killer cell partnerships in early mouse decidua basalis

Interactions of the ligand/receptor pair LFA- 1(CD11a/ CD18) and ICAM-1(CD54) initiate and control the cell-cell interactions of leukocytes and interactions of leukocytes with parenchymal cells in all phases of the immune response. Induction of the intercellular adhesion molecule 1 (ICAM-1) on the surface of epidermal keratinocytes has been proposed as an important regulator of contact-dependent aspects of cutaneous inflammation. Ultraviolet radiation (UVR) also modifies cutaneous inflammation, producing both up- and down-regulation of contact hypersensitivity. We have found that UVR has a biphasic effect on the induction of keratinocyte CD54. Using immunofluorescence and FACS techniques to quantitate cell-surface CD54 staining, we have shown that UVR (100 mJ/cm2 of UVB) significantly (p <0.01) inhibits keratinocyte CD54 induction by gamma interferon 24 h after irradiation. However, at 48, 72, and 96 h after UVR (10 to 100 mJ/cm2), CD54 expression is significantly induced (p <0.01 to p < 0.00 1) to levels even greater than are induced by gamma interferon (20 U/ml). In addition, at 48, 72, or 96 h following UVR (30-100 mJ/cm2) the gamma-interferon – induced CD54 expression on human keratinocytes is also strongly (p < 0.05 to p <0.001) enhanced. In this cell-culture system, gamma interferon and TNF-α are both strong CD54 inducers and are synergistic but GM-CSF, TFG-β, and IL-1 have no direct CD54-inducing effects. Thus the effects of UVR on CD54 induction are biphasic, producing inhibition at 24 h and induction at 48, 72, and 96 h. This effect on CD54 may contribute to the biphasic effect of UVR on delayed hypersensitivity in vivo. The early inhibition of ICAM-1 by UVR may also contribute to the therapeutic effects of UVR. We also speculate that the late induction of ICAM-1 by UVR might be an important step in the induction of photosensitive diseases such as lupus erythema tosus.

Laboratory diagnosis of pemphigus: direct immunofluorescence remains the gold standard

Pemphigus is a life-threatening autoimmune bullous disease that is characterized by intraepithelial blistering of skin and/or mucous membranes, by the in vivo deposition of immunoglobulin (Ig) G on the cell surface of keratinocytes and the presence of such IgG in the circulation(1) . This article is protected by copyright. All rights reserved.

Multiplexed autoantigen microarrays identify HLA as a key driver of anti-desmoglein and -non-desmoglein reactivities in pemphigus

Patients with pemphigus vulgaris (PV) harbor antibodies reactive against self-antigens expressed at the surface of keratinocytes, primarily desmoglein (Dsg) 3 and, to a lesser extent, Dsg1. Conventionally, only antibodies targeting these molecules have been thought to contribute to disease pathogenesis. This notion has been challenged by a growing pool of evidence that suggests that antibodies toward additional targets may play a role in disease. The aims of this study were to (i) establish high-throughput protein microarray technology as a method to investigate traditional and putative autoantibodies (autoAbs) in PV and (ii) use multiplexed protein array technology to define the scope and specificity of the autoAb response in PV. Our analysis demonstrated significant IgG reactivity in patients with PV toward the muscarinic acetylcholine receptor subtypes 3, 4, and 5 as well as thyroid peroxidase. Furthermore, we found that healthy first- and second-degree relatives of patients with PV express autoAbs toward desmoglein and non-Dsg targets. Our analysis also identified genetic elements, particularly HLA, as key drivers of autoAb expression. Finally, we show that patients with PV exhibit significantly reduced IgM reactivity toward disease-associated antigens relative to controls. The use of protein microarrays to profile the autoAb response in PV advanced the current understanding of disease and provided insight into the complex relationship between genetics and disease development.

Mucin1 expression in focal epidermal dysplasia of actinic keratosis.

Actinic keratoses (AKs) are generally considered as premalignant skin lesions that can progress into squamous cell carcinoma (SCC) in situ and invasive SCC. However, its progression to SCC is still matter of debate. A transmembrane glycoprotein that contributes to the progression of certain premalignant and malignant lesions is mucin1 (MUC1). Nevertheless, their functions in the skin lesions are not yet fully clear. Therefore, the aim of this study is to ascertain whether MUC1 is present in the focal epidermal dysplasia of AK. Fourteen skin biopsies from patients diagnosed with AK were selected. They were classified according to the degree of dysplasia in keratinocyte intraepidermal neoplasia (KIN) I, KIN II, and KIN III. In five biopsies the three degrees were present, in two biopsies both KIN I and KIN II, in four biopsies only KIN I, and in three biopsies only KIN III. The presence of MUC1 was assessed by immunofluorescence staining using confocal laser scanning microscopy. Immunostaining revealed that MUC1 was present over the entire cell surface of only a few atypical basal keratinocytes confined to the lower third of the epidermis (KIN I). While in KIN II where atypical keratinocytes occupy the lower two thirds, MUC1 was localized at the apical surface of some atypical keratinocytes and over the entire cell surface of some of them. Interestingly, in KIN III where the atypical keratinocytes extend throughout the full thickness, MUC1 was localized at the apical surface and over the entire cell surface of many of these cells. Conversely, MUC1 expression was not detected in the epidermis of normal skin. Our findings suggest that the expression of MUC1 in AK would be induced by alteration of keratinocyte stratification and differentiation and associated to the degree of dysplasia rather than the thickness of the epidermis.

Lichen planus and lichenoid reactions as a systemic disease

Lichen planus (LP) is a chronic disease that involves the skin, scalp, mucous membranes, and nails. The etiology of LP is still unknown; however, some external and internal factors (eg. drugs, stress, hepatitis C virus) have been suggested to trigger the disease. Many studies have investigated an immunologic pathogenesis that is probably related to T-cell autoimmunity with the keratinocyte as the target cell. Altered self-antigens on the surface of basal keratinocytes modified by viruses or by drugs are believed to be the targets of the T-cell response. Various drugs and contact allergens like amalgam may cause lichenoid reactions, which are the main differential diagnoses of LP. Clinically and histologically, LP and lichenoid reactions cannot be distinguished with certainty in many cases. Treatment is mainly symptomatic and can be difficult. The first-line therapies for LP are topical or systemic corticosteroids; however, some studies have mentioned acitretin leading to similar improvement. Medical treatment, together with patient education and psychosocial support, can significantly benefit patients’ quality of life.

Vaccinia Virus Binds to the Scavenger Receptor MARCO on the Surface of Keratinocytes

Patients with altered skin immunity, such as individuals with atopic dermatitis (AD), can have a life-threatening disruption of the epidermis known as eczema vaccinatum (EV) after vaccinia virus (VV) infection of the skin. Here, we sought to better understand the mechanism(s) by which VV associates with keratinocytes. The class A scavenger receptor known as MARCO (macrophage receptor with collagenous structure) is expressed on human and mouse keratinocytes and found to be abundantly expressed in the skin of patients with AD. VV bound directly to MARCO, and overexpression of MARCO increased susceptibility to VV infection. Furthermore, ligands with affinity for MARCO, or excess soluble MARCO, competitively inhibited VV infection. These findings indicate that MARCO promotes VV infection and highlights potential new therapeutic strategies for prevention of VV infection in the skin.

Presence of MUC1 in the epidermal thickening of psoriatic plaques.

Mucin 1 (MUC1) is a transmembrane glycoprotein that protects epithelial cells from injury caused by external stimuli. In addition to this role, MUC1 is involved in cell-cell adhesion, proliferation, motility, invasion and survival. In epithelial cells, MUC1 expression is regulated by binding of TNFα to TNFR1 and activation of the NFκB pathway. In human skin, MUC1 is not expressed in normal epidermis but rather in pre-malignant and malignant conditions. Nevertheless, the expression of MUC1 and its implication in psoriasis vulgaris has not been considered. Here, we show that MUC1 was present in the epidermis of psoriatic plaques observed in 11 biopsies from patients diagnosed with psoriasis vulgaris which were compared with 5 normal human skin. Interestingly, MUC1 in addition to being localized at the apical surface of some suprabasal keratinocytes, was also localized over the entire cell surface of some of these cells and some basal keratinocytes. Conversely, no MUC1 immunoreactivity was detected in the epidermis of normal skin. Additionally, we demonstrated that activated TNFR1, c-Src, IKKα/β and p50/p65 were present in the epidermal thickening. This study demonstrates the presence of MUC1 in psoriatic plaque and suggests a possible role for MUC1 during the motility, migration and survival of human keratinocytes, where activated TNFR1, c-Src and NFκB seem to be required.

Entry Mechanisms of Herpes Simplex Virus 1 into Murine Epidermis: Involvement of Nectin-1 and Herpesvirus Entry Mediator as Cellular Receptors

Skin keratinocytes represent a primary entry site for herpes simplex virus 1 (HSV-1) in vivo. The cellular proteins nectin-1 and herpesvirus entry mediator (HVEM) act as efficient receptors for both serotypes of HSV and are sufficient for disease development mediated by HSV-2 in mice. How HSV-1 enters skin and whether both nectin-1 and HVEM are involved are not known. We addressed the impact of nectin-1 during entry of HSV-1 into murine epidermis and investigated the putative contribution of HVEM. Using ex vivo infection of murine epidermis, we showed that HSV-1 entered the basal keratinocytes of the epidermis very efficiently. In nectin-1-deficient epidermis, entry was strongly reduced. Almost no entry was observed, however, in nectin-1-deficient keratinocytes grown in culture. This observation correlated with the presence of HVEM on the keratinocyte surface in epidermis and with the lack of HVEM expression in nectin-1-deficient primary keratinocytes. Our results suggest that nectin-1 is the primary receptor in epidermis, while HVEM has a more limited role. For primary murine keratinocytes, on which nectin-1 acts as a single receptor, electron microscopy suggested that HSV-1 can enter both by direct fusion with the plasma membrane and via endocytic vesicles. Thus, we concluded that nectin-1 directs internalization into keratinocytes via alternative pathways. In summary, HSV-1 entry into epidermis was shown to strongly depend on the presence of nectin-1, but the restricted presence of HVEM can potentially replace nectin-1 as a receptor, illustrating the flexibility employed by HSV-1 to efficiently invade tissue in vivo. Herpes simplex virus (HSV) can cause a range of diseases in humans, from uncomplicated mucocutaneous lesions to life-threatening infections. The skin is one target tissue of HSV, and the question of how the virus overcomes the protective skin barrier and penetrates into the tissue to reach its receptors is still open. Previous studies analyzing entry into cells grown in vitro revealed nectin-1 and HVEM as HSV receptors. To explore the contributions of nectin-1 and HVEM to entry into a natural target tissue, we established an ex vivo infection model. Using nectin-1- or HVEM-deficient mice, we demonstrated the distinct involvement of nectin-1 and HVEM for HSV-1 entry into epidermis and characterized the internalization pathways. Such advances in understanding the involvement of receptors in tissue are essential preconditions for unraveling HSV invasion of skin, which in turn will allow the development of antiviral reagents.

A preliminary study on clinical outcome of corticosteroid therapy in pemphigus patients

Introduction: Pemphigus is life threating blistering of autoimmune disease of the skin and mucous membrane characterised by autoantibodies (auto ABs) against desmoglein-3 (DSG-3). Desmosomal adhesions, protein expressed on the surface of epidermal keratinocytes. Aim: The present study was to assess the incidence rate of pemphigus, to evaluate the clinical course along with clinical manifestations, Complications and Metabolic factors of patients with pemphigus and to investigate the disease severity and induction of remission during the clinical course and whereas to assess the oxidative stress and antioxidant status in pemphigus patients in our hospital. Material and Methods: A prospective study was conducted over a period of January 2012 to December 2012 at dermatology department, MGM Hospital, Warangal. The data was collected from 32 cases of Pemphigus on the basis of Age, Sex, Social Habits, BMI, Histopathological forms, Clinical manifestations and Drug therapy. This hospital is 1200 bedded government hospital provided Outpatient and Inpatient care for Indian citizen especially in Telangana region free of cost. Results: Of the 32 pemphigus patients, 75% were diagnosed with Pemphigus Vulgaris (PV), 12.5% with Pemphigus Foliaceus (PF) and 12.5% with Bullous Pemphigoid (BP). The male to female ratio was approximately 1:1.3. The mean age of onset was 40.8 years in Pemphigus patients. The Onset of disease was 29.85. 34% of patients with Pemphigus had both the mucosal and skin involvement during the clinical course while 25% at the onset of disease. The most common complication was found to be increase blood sugar (40%). Most commonly prescribed adjuvant is dapsone. Majority attained the complete remission and remaining of them attains partial remission. Oxidative stress levels were higher and antioxidant status levels were lower in study subjects when compared to controls. Conclusions: PV is the most common subtype of Pemphigus in our Hospital and usually affects females more than males. Our study reveals that mucosal and skin involvement is common. Corticosteroids and dapsone as adjuvant is majorly prescribed. Most of patients attain complete remission and remaining of them achieves partial remission. Oxidative stress levels were higher and antioxidant status levels were lower in our study subjects when compared to controls.

Candida albicans Uses the Surface Protein Gpm1 to Attach to Human Endothelial Cells and to Keratinocytes via the Adhesive Protein Vitronectin

Candida albicans is a major cause of invasive fungal infections worldwide. Upon infection and when in contact with human plasma as well as body fluids the fungus is challenged by the activated complement system a central part of the human innate immune response. C. albicans controls and evades host complement attack by binding several human complement regulators like Factor H, Factor H-like protein 1 and C4BP to the surface. Gpm1 (Phosphoglycerate mutase 1) is one fungal Factor H/FHL1 -binding protein. As Gpm1 is surface exposed, we asked whether Gpm1 also contributes to host cell attachment. Here, we show by flow cytometry and by laser scanning microscopy that candida Gpm1 binds to human umbilical vein endothelial cells (HUVEC) to keratinocytes (HaCaT), and also to monocytic U937 cells. Wild type candida did bind, but the candida gpm1Δ/Δ knock-out mutant did not bind to these human cells. In addition Gpm1when attached to latex beads also conferred attachment to human endothelial cells. When analyzing Gpm1-binding to a panel of extracellular matrix proteins, the human glycoprotein vitronectin was identified as a new Gpm1 ligand. Vitronectin is a component of the extracellular matrix and also a regulator of the terminal complement pathway. Vitronectin is present on the surface of HUVEC and keratinocytes and acts as a surface ligand for fungal Gpm1. Gpm1 and vitronectin colocalize on the surface of HUVEC and HaCaT as revealed by laser scanning microscopy. The Gpm1 vitronectin interaction is inhibited by heparin and the interaction is also ionic strength dependent. Taken together, Gpm1 the candida surface protein binds to vitronectin and mediates fungal adhesion to human endothelial cells. Thus fungal Gpm1 and human vitronectin represent a new set of proteins that are relevant for fungal attachment to human cells interaction. Blockade of the Gpm1 vitronectin interaction might provide a new target for therapy.