Keratinocyte Apoptosis Research Articles

High Serum Level of TNF-α in Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis are severe cutaneous adverse drug reactions. Some immunological and genetic factors are believed to be involved in the pathogenesis of SJS/TEN, including tumor necrotic factor-alpha (TNF-α). Activated T-cells secrete high amounts of TNF-α and interferon-gamma that both cytokines lead to increased expression and activity of keratinocyte inducible nitric oxide synthase playing an important role in the apoptosis of keratinocytes. AIM: This study aims to evaluate the serum level of TNF-α in SJS/TEN and the relation between it and the progress of SJS/TEN. METHODS: This was a sectional descriptive study conducted at the National Hospital of Dermatology and Venereology, in Hanoi, Vietnam, from October 2017 to September 2019. Forty-eight SJS/TEN patients, 43 erythema multiforme (EM) patients, and 20 healthy controls (HCs) participated. TNF-α levels were measured using the fluorescence covalent microbead immunosorbent assay (FCMIA) (ProcartaPlex Immunoassay Panels kit, Thermo Fisher Scientific, USA). The Mann–Whitney U-test was used to compare serum TNF-α levels of two groups. The Wilcoxon tests were used to compare quantitative variables before and after the treatment. Differences were considered to be statistically significant at p < 0.05. RESULTS: Nineteen SJS patients (39.5%) and 29 TEN patients (60.5%) participated in our study. The mean age was 49.3, range 19−77 years (47.9% of males and 52.1% of females). The most common causative drugs were traditional medicine (29.1%), carbamazepine (12.5%), and allopurinol (12.5%). On the day of hospitalization, the mean serum level of the SJS/TEN group was 32.6 pg/ml with a range from 1.3 pg/ml to 771.2 pg/ml. This level was significantly higher than that of the HCs group (p < 0.05) but not higher than that of the EM group. The mean serum level of TNF-α in the SJS/TEN patients on the day of hospitalization was 32.6 pg/ml, higher than that on the day of re-epithelialization (2.7 pg/ml) and the difference was statistically significant with p < 0.05. CONCLUSION: Serum TNF-α levels are a good biomarker to evaluate the progress of SJS/TEN but it is not good to differentiate SJS/TEN from EM.

ODP265 Bph, Androgenic Alopecia, and Acne - Markers of Progesterone Deficiency

Abstract Materials and methods The study at this stage involves 6 male patients from 21 to 50 years with the diagnosis: BPH. Androgenic alopecia. Acne disease. All patients were examined for vitamin D in the blood by calcidiol 25(OH)D using mass spectrometry and steroid hormone levelsusing a steroid profile in saliva by mass spectrometry. Findings. Vitamin D level in three patients was below 30 ng/ml, in three patients - below 20 ng/ml. The steroid profile in the saliva of all six patients revealed progesterone deficiency, with normal testosterone levels. Patients were prescribed vitamin D in a dose of 20,000 IU daily and progesterone in a dose of 100 mg daily; patients with acne were additionally prescribed topical treatment - progesterone in gel form. As a result, after 6 months of using this therapy, patients have a cessation of hair loss, growth of downy hair and transition of downy hair to terminal hair,improvement in all patients was 80-90%. Two patients with the papulopustular form of moderate acne improved by 90%, a patient with the conglobate form improved by 50% (transition to the papulopustular form of moderate severity). Improvement of clinical picture of symptoms of BPH is also noted: decrease of IPSS questionnaire score to 7-9. Vitamin D level from 70 to 100 ng/ml. On the steroid profile of saliva, the levels of testosterone and progesterone are within normal limits. Interpretation. The main cause of androgenetic alopecia, acne, BPH is thought to be: an excess of DHT (dihydrotestosterone), increased activity of 5-α-reductase enzyme. These three diseases accompany each other. The main drug which is used 5-α-reductase blockers. The side effects of which greatly exceed the benefitsof treating. Vitamin D is involved in regulation of proliferation, differentiation and apoptosis of keratinocytes, regulation of skin immunity, regulation of pro-inflammatory cytokines, stimulation of the expression of antimicrobial peptides, regulation of the integrity and permeability of the lipid barrier, reducing the severity of systemic inflammation, regulation of cellular, humoral, congenital and acquired immunity. Also, in an in vitro study it was found that progesterone can inhibit the activity of 5-α-reductase, so in the skin the activity of this enzyme is reduced by 97±5.3%. And the positive effect was also established in the treatment of prostate diseases, inhibiting 5-α-reductase, progesterone reduces the growth of the prostate gland and the growth of prostate cancer cells. Conclusion Laboratory studies have shown vitamin D and progesterone deficiencies in patients with these diseases. Correction of these deficiencies resulted in improvement both in BPH (reduction of clinical manifestations) and in androgenic alopecia (cessation of hair loss and restoration of terminal hair growth) and acne (significant reduction of inflammation). Presentation: No date and time listed

MANAGEMENT OF ULCERATIVE ORAL LICHEN PLANUS PREDISPOSED BY PSYCHOLOGICAL STRESS

Background: Oral lichen planus (OLP) is a chronic inflammatory autoimmune oral mucosa disease. The ulcerative type of OLP presents as erythematous ulceration with mucosal erosions surrounding whitish striae. The aetiology of OLP is unknown, but can be predisposed by psychological factors. Purpose: Reporting ulcerative oral lichen planus predisposed by psychological stress. Case: A 36 years old woman complained very painful ulcer in the right buccal mucosa and a grey-purple lower lip lesion for a year. It had been treated with topical corticosteroids, antibiotics, tretinoin, and vitamins but did not heal. Extraoral examination on the lower vermillion showed bluish-purple macules, diffuse and irregular borders, rough and painful. Intraoral examination in the right buccal mucosa showed an irregular yellowish-white ulcer with an erythematous area and white striae. Case Management: Screening for psychological stress by DASS 42 showed moderate stress and severe anxiety. Autofluorescence examination showed no malignant transformation sign. A complete blood count test showed low neutrophil and lymphocyte count. ANA test was normal. Systemic Methyl Prednisolone 8 mg was prescribed 2 tabs twice a day and tapered off after the lesion resolved within 1 week. Supportive treatments include Benzydamine HCl and multivitamins. Discussion: Stress, anxiety, and depression were possible factors of OLP mediated by the Hypothalamic-pituitary-adrenal (HPA) axis system and the Sympathetic-adrenal-medullary (SAM) system. Specific mechanisms are mediated by Antigen-specific CD8+ (CTLs) that are activated with the help of CD4+ T-cells. Non-specific mechanism mediated by MMP-9 activation. They led to the apoptosis of keratinocytes. Systemic corticosteroids are an important treatment for oral lichen planus that do not responded to topical steroids. Conclusion: Oral Lichen Planus is a chronic inflammatory disease that affects the oral mucosa and can be predisposed by psychological stress. Corticosteroid is very effective to treat oral lichen planus, especially the erosive-ulcerative type. Keywords: Oral Lichen Planus, Psychological Stress, Ulcerative

Staphylococcus aureus skin colonization promotes SLE-like autoimmune inflammation via neutrophil activation and the IL-23/IL-17 axis.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by inflammation of various organs such as skin, kidneys, bones, and brain and the presence of autoantibodies. Although the cause of SLE is not completely understood, environmental factors, genetic susceptibility, hormone factors, and environmental factors are thought to play essential roles in the pathogenesis of SLE. Among environmental factors, the microbiota are linked to the development of different autoimmune diseases. The microbiota in the nasal cavity and gut are involved in SLE development, but the influence of skin microbiota is still unclear. Here, we demonstrated that epithelial cell-specific IκBζ-deficient (NfkbizΔK5) mice showed spontaneous skin inflammation with increased abundance of Staphylococcus aureus on the skin. When S. aureus was epicutaneously applied on NfkbizΔK5 mice, NfkbizΔK5 mice developed SLE-associated autoantibodies, anti-dsDNA antibodies, anti-Sm antibodies, and glomerulonephritis with IgG deposition. Epicutaneous S. aureus application significantly increased staphylococcal colonization on the skin of NfkbizΔK5 mice with reduced expression of several antimicrobial peptides in the skin. This staphylococcal skin colonization promoted caspase-mediated keratinocyte apoptosis and neutrophil activation, inducing the interleukin-23 (IL-23)/IL-17 immune response by activating dendritic cells and T cells. Furthermore, the subcutaneous administration of anti-IL-23p19 and anti-IL-17A antibodies alleviated the systemic autoimmune response. Together, these findings underscore epithelial-immune cross-talk disturbances caused by skin dysbiosis as an essential mediator inducing autoimmune diseases.

Here\'s what really matters in vitiligo; Vitamin D3 and lifestyle

Epidermal melanocyte deficit is the basis of Vitiligo. It is a prolonged condition that may be inherited or acquired. Vitiligo affects 1-2 percent of the global population of all races. Several processes have been hypothesized for the breakdown of melanocytes in Vitiligo. These include genetic, autoimmune, oxidative stress, inflammatory mediator production, and melanocyte detachment processes.Vitamin D suppresses UVB-induced apoptosis in keratinocytes and melanocytes by reducing IL-6, IL-8, TNF-a, and TNF-c production. It reduces the autoimmune linked to Vitiligo.We conducted a case-control study in which we compared the level of Vitamin D in patients with Vitiligo and healthy cases. We confirmed our diagnosis with biopsy and utilized the Elisa method to assess the level of Vitamin D. The concentrations of Vitamin D in individuals with Vitiligo were much lower than in controls; however, we did not find a significant effect of vitamin D deficiency on the progression of Vitiligo lesions. Therefore we conclude that Vitamin D is involved in the genesis of Vitiligo, and replenishing the levels may help the patient recover faster.

The effect of curcumin on the cadmium-induced mitochondrial apoptosis pathway by metallothionein 2A regulation

Cadmium (Cd) is one of the most toxic heavy metals used in various industries, including metal plating, batteries and plastics and environmental pollutant. Cd in the environment is a detrimental factor that cannot be biodegraded and accumulates in human organs. The skin is the first target organ after Cd topical exposure. Curcumin is a natural dietary polyphenolic compound with many beneficial effects, including antioxidant, anti-inflammatory and anticancer activities. However, the effect of curcumin against Cd-induced toxicity in human keratinocytes has not been reported. In this study, we investigated the effects of curcumin against Cd-induced apoptosis in keratinocytes and the underlying molecular mechanisms. Cd resulted in apoptosis as shown by Annexin V/7-AAD double staining. Cd promoted the cleavage of poly (ADP ribose) polymerase-1 (PARP-1) and caspase 3 and suppressed Bcl-2. In addition, Cd induced the release of cytochrome c and Smac from the mitochondria into the cytosol, which is an intrinsic apoptosis-specific process. Curcumin inhibited the early and late apoptosis caused by Cd. The changes in apoptotic markers induced by Cd were significantly reversed by curcumin. Next, we evaluated the effect of curcumin on metallothionein (MT), a cysteine-rich protein that plays a key role in metal detoxification. Curcumin increased the level of MT2A mRNA and the expression of MT2. Interestingly, the antiapoptotic effects of curcumin were reversed under the knockdown of MT2A, suggesting that MT2A is a critical target of curcumin. These findings indicate the potential of curcumin as a novel compound for protection against Cd-mediated skin damage by MT2A modulation.

Dermatopathology of COVID-19 infection and vaccination.

BackgroundMany peculiar skin changes have been described in relation to both coronavirus disease 2019 (COVID-19) infection and vaccination.ObjectiveThis paper provides an overview of these dermatologic manifestations, focusing on their dermatopathological appearances.ResultsMost COVID-19 patients develop variegated maculopapular eruptions with a combination of histological patterns commonly including keratinocyte apoptosis and eosinophilia. Urticaria-like lesions often show a combination of spongiotic and lichenoid patterns and are more frequent in individuals with severe disease. Vesicular lesions can be disseminated; in some cases, they become pustular and in others show dyskeratosis and a peculiar form of ballooning. Some patients develop vesicular Grover disease on the trunk. Young patients with a strong immunological response can eliminate the virus easily but may develop chilblains as a consequence of the high interferon response. Conversely, older individuals with immunosenescence and a tendency toward hypercoagulability can present livedoid and ischemic areas. Regarding COVID-19 vaccination, hypersensitivity reactions are most frequent, including “COVID-arm.” Nonetheless, a combination of local and systemic cutaneous manifestations (reactogenicity) is commonly seen. Histopathologically, lichenoid and spongiotic changes and a variable number of eosinophils are typical of rashes characterized by papules and plaques. Other dermatological side effects of COVID-19 vaccination include lesions mimicking well-defined dermatoses such as lichen planus or bullous pemphigoid and triggering of collagenous diseases.ConclusionWell-characterized skin manifestations of coronavirus disease 2019 (COVID-19) include chilblains, livedo necrotic lesions, vesicular eruptions, urticarial lesions, and maculopapular eruptions. Hypersensitivity reactions are common after SARS-CoV‑2 mRNA vaccination. Vaccine reactions may also mimic other dermatosis such as bullous pemphigoid or lichen planus, stimulate herpes reactivation, or trigger the development of autoimmune diseases.

Sonodynamic therapy by phase-transition nanodroplets for reducing epidermal hyperplasia in psoriasis.

The cross-talk between hyperproliferative keratinocytes and activated immune cells is responsible for the progression of psoriasis. The strategy to alleviate psoriasis through inhibiting the abnormal proliferation of keratinocytes remains challenging due to limited therapeutic effects and low skin penetration of drugs. Herein we designed an ultrasound-triggered phase-transition nanodroplet that could produce cavitation to enhance skin penetration and effectively generate reactive oxygen species (ROS) to induce keratinocyte apoptosis for psoriasis treatment. After ultrasound stimulation, the perfluoro-n-pentane (PFP) liquid core of the nanodroplets vaporized, and the Haematoporphyrin monomethyl ether (HMME) encapsulated in the nanodroplets generated plenty of intracellular ROS which caused the apoptosis of HaCat cells through inducing mitochondrial dysfunction. In addition, the blank nanodroplets successfully inhibited the secretion of IL-6 and TNF-α from macrophages and dendritic cells in vitro due to the anti-inflammatory effect of POPG. For the skin penetration test, the phase-transition nanodroplets could effectively accumulate in the epidermis of the skin and generate intracellular ROS. The in-vivo anti-psoriasis experiment demonstrated that the phase-transition nanodroplets relieved the symptoms of psoriasis lesion and inhibited epidermal hyperplasia through induction of cell apoptosis under ultrasound irritation. Meanwhile, the inflammatory cytokines in the skin lesion almost decreased to the normal baseline level after SDT. Collectively, this study demonstrated a new strategy to inhibit keratinocyte hyperproliferation for psoriasis management based on sonodynamic responded nanodroplets.

The Protective Effects of Sodium Pentaborate Tetrahydrate Against UVB-induced Apoptosis in Human Keratinocytes

Ultraviolet radiation (UV) is an environmental carcinogen causing human skin cancer. Exposure of the skin to UV produces apoptotic keratinocytes called sunburn cells within the epidermis. Boron, an essential element for plants, has several biological properties, such as anti-cancer, anti-microbial, and anti-oxidant. In the present study, the possible protective effects of sodium pentaborate pentahydrate (SPT) against UVB-induced apoptosis in human keratinocyte cells, HaCaT, were investigated. They were treated with SPT at different concentrations (7.8-125 μg/mL) for 24h after UVB irradiation (20, 30 and 60mJ/cm2). Cell viability, annexin V assay, cell cycle analysis, and apoptosis-related gene levels were measured using RT-PCR. Treatment with SPT (15.6-31.25μg/mL) after 30 mJ/m2 UVB exposure significantly increased cell survival. Annexin V apoptosis analysis demonstrated a robust protective effect by treatment with SPT at concentrations of 15.6 and 31.25μg/mL after 30mJ/cm2 UVB irradiation. The cell cycle analysis revealed that UVB irradiation elevated the number of cells at the G0/G1 phase while SPT treatment after UVB irradiation increased the number of cells at G2/M phase, suggesting the changes were partially reversed. Furthermore, treatment with 15.6μg/mL SPT after 30 mJ/m2 UV irradiation blocked the activation of caspase 3, caspase 9, Bax, and p53. These results indicate that treatment with SPT exerts protective effects after UVB irradiation. Thus, treatment with SPT led to strong protection against UVB-induced apoptotic cell death in HaCaT cells.

Evaluation of locking compression plate fixation of the distal phalanx to the hoof wall as a potential therapy for laminitis.

Surgical stabilisation of the distal phalanx (DP) is a potential therapeutic strategy for severe acute laminitis. To evaluate the effects of locking compression plate (LCP) fixation of the DP to the dorsal hoof wall. Ex vivo and in vivo experiments. A T-shaped LCP was applied to one limb per pair in six pairs of cadaver forelimbs subjected to a combination of thermally induced lamellar failure and vertical load to simulate severe acute laminitis. Standard radiographic measurements were used to compare DP displacement. The LCP was then applied to one forefoot in 12 healthy Standardbred horses either standing (n=6) or under general anaesthesia (n=6). Lameness was evaluated daily, then horses were euthanised (day 8) and lamellar tissue analysed using light microscopy, histomorphometery and molecular markers of apoptosis. In the cadaver limb model, LCP fixation prevented the significant changes in hoof-distal phalanx distance, coronary extensor process distance and sole depth that characterised DP displacement in untreated limbs (p < 0.05). Application of the construct in vivo was well tolerated with minimal lameness (10/12 horses were sound at the trot on day 8); however, histology revealed dorsal lamellar pathology consistent with laminitis, but with extensive keratinocyte apoptosis. Adjacent to the LCP, caspase-3 positive cell counts were approximately 20-fold higher than control (p < 0.001). Pathology was evaluated at a single time point. Microvascular perfusion was not evaluated. Rigid fixation of the DP to the hoof capsule was achieved with the LCP construct in a cadaver limb laminitis model. In live horses, LCP fixation caused regional lamellar pathology with extensive apoptosis, likely due to disturbed lamellar microvascular perfusion and/or mechanostasis. Understanding these mechanisms is critical for refinement of the technique in order to avoid iatrogenic lamellar damage.

Dual RNA-Sequencing and Liquid Chromatography–Mass Spectrometry Unveil Specific Insights on the Pathogenicity of Trichophyton mentagrophytes Complex

Trichophyton mentagrophytes is increasingly considered to be a public health hazard because it causes the most severe manifestations of dermatophytosis. In this study, we performed a series of studies to determine the pathogenicity of the T.mentagrophytes complex. We show that the T.mentagrophytes complex interacts with keratinocytes through pattern-recognition receptors‒MAPK/noncanonical NF-κB pathways and that the hyphal form of T.mentagrophytes is responsible for the increased inflammatory responses in keratinocytes. Moreover, SN-38 is likely a toxin of T.mentagrophytes that induces apoptosis in keratinocytes both invivo and invitro. Our results explain the severe pathogenicity and destructiveness of T.mentagrophytes observed in the clinic and pave the way for designing novel toxin-directed therapies to improve patient outcomes.

Advanced oxidation protein products mediatehuman keratinocytes apoptosis by inducing cell autophagy through the mTOR-Beclin-1 pathway.

Excessive keratinocyte apoptosis leads to impaired wound healing. Recently, advanced oxidation protein products (AOPP) have been recognized as a marker of oxidative stress and a potent inducer of apoptosis. Previously, we have demonstrated that extracellular AOPP accumulation induced keratinocyte apoptosis, and we discovered that autophagy was involved. To further elucidate the role and mechanism of autophagy in AOPP-induced-apoptosis of keratinocytes, we treated HaCaT cells with increasing concentrations of AOPP-human serum albumin or with AOPP-human serum albumin for increasing durations. Cyto-ID solution staining was used to assess cell autophagy using confocal laser scanning microscopy. Autophagy-related protein interactions were investigated using western blot analysis. Exposure of HaCaT cells to AOPP decreased the expression of mammalian target of rapamycin (mTOR) and increased the expression of autophagy-related proteins Beclin-l and LC3, and eventually led to autophagy. Furthermore, an autophagy agonist significantly decreased the expression of apoptosis-related proteins. Taken together, we showed that accumulation of extracellular AOPP induced autophagy in HaCaT cells via a reactive oxygen species-dependent, mTOR-Beclin-1-mediated pathway, and that excessive autophagy-mediated apoptosis, which resulted in delayed wound healing.

Arbutin Inhibited Heat Stress-Induced Apoptosis and Promoted Proliferation and Migration of Heat-Injured Dermal Fibroblasts and Keratinocytes by Activating PI3K/AKT Signaling Pathway.

Objective Studies have shown that arbutin has antioxidant and anti-inflammatory activities, which makes it suitable for treating skin wounds. We designed this study to investigate the effect of arbutin on heat-induced apoptosis, proliferation, and migration of dermal fibroblasts and keratinocytes and to explore the molecular mechanism. Methods In vitro, HaCAT and dermal fibroblast (DFL) cells were cultured and used to establish a heat stress-injured skin cell model. We investigated the effects of arbutin on apoptosis, proliferation, and migration of HaCAT and DFL cells after heat stress injury. We then used immunoblotting to detect the expression of p-PI3K, PI3K, p-AKT, and AKT proteins for studying the underlying mechanisms and used a PI3K/AKT inhibitor (LY294002) to verify the efficacy of arbutin in HaCAT and DFL cells with heat stress injury. Results Arbutin strongly inhibited heat stress-induced apoptosis, proliferation inhibition, and migration inhibition of HaCAT and DFL cells in vitro. Our results also showed that arbutin strongly decreased the ratio of Bax/Bcl2 protein expression and PCNA protein expression in HaCAT and DFL cells after treatment with heat stress. Furthermore, we also found that arbutin significantly increased the ratio of p-PI3K/PI3K and p-AKT/AKT protein expression, and LY294002 markedly reversed the effect of arbutin on heat stress-induced apoptosis, proliferation inhibition, and migration inhibition of HaCAT and DFL cells. Conclusion Our finding indicated that arbutin inhibited heat stress-induced apoptosis and promoted proliferation and migration of heat-injured dermal fibroblasts and epidermal cells by activating the PI3K/AKT signaling pathway, suggesting that arbutin may provide an alternative therapeutic approach for the treatment of skin injury.

Curcumin Improves Keratinocyte Proliferation, Inflammation, and Oxidative Stress through Mediating the SPAG5/FOXM1 Axis in an In Vitro Model of Actinic Dermatitis by Ultraviolet.

Background Chronic actinic dermatitis (CAD) is an abnormally proliferating photoallergic skin disease. Dysregulated inflammation and oxidative stress are the immediate factors in the abnormal proliferation of keratinocytes. This study aimed to investigate the effect of curcumin on the aberrant proliferation of keratinocytes in an in vitro (actinic dermatitis) AD model and the possible molecular mechanisms. Methods The keratinocytes were irradiated with ultraviolet (UV) to construct an in vitro AD model and then processed with different concentrations of curcumin. Cell viability, oxidative stress markers (SOD, GSH-PX, and MDA), activated oxygen species (ROS), and inflammation markers (IL-1β, IL-6, IL-18, and TNFα) were determined, respectively. Western blot was applied to assay the profiles of apoptosis-related proteins (Bax, Bcl-xL, Caspase3, Caspase8, and Caspase9), oxidative stress proteins (Keap1, Nrf2, HO-1, COX2, and iNOS), and inflammatory proteins (NF-κB, MMP1, and MMP9) and SPAG5/FOXM1. Functionally, SPAG5 or FOXM1 overexpression and knockdown models were constructed in keratinocytes to characterize their influence on UV irradiation-mediated keratinocyte dysfunction. Results Curcumin weakened UV-mediated inflammation, proliferation, and oxidative stress and impaired apoptosis in keratinocytes. UV boosted SPAG5/FOXM1 expression in cells, while curcumin concentration-dependently retarded SPAG5/FOXM1 expression. Overexpression of SPAG5/FOXM1 fostered UV-mediated inflammation, proliferation, oxidative stress, and intensified apoptosis, whereas curcumin mostly reversed the SPAG5/FOXM1-mediated effects. In addition, knocking down SPAG5/FOXM1 ameliorated UV-mediated keratinocyte dysfunction, whereas curcumin failed to exert further protective effects in cells with knockdown of SPAG5/FOXM1. Conclusion Curcumin modulated proliferation, inflammation, oxidative stress, and apoptosis of keratinocytes by restraining the SPAG5/FOXM1 axis.

Plasma Exosomes from Children with Atopic Dermatitis May Promote Apoptosis of Keratinocytes and Secretion of Inflammatory Factors in vitro.

PurposeExosomes are important regulators of keratinocytes (KCs) that have been implicated in a variety of skin disorders. The effect of circulatory exosomes on KCs in pediatric atopic dermatitis (AD) has not been well studied. This study aims to explore the effect of plasma exosomes on KC activation, apoptosis and inflammation in pediatric AD patients.Patients and MethodsExosomes were extracted from plasma collected from 20 pediatric AD patients and 20 age-matched healthy controls. AD-exosomes were added with KCs at concentrations of 0 g/L, 10 g/L, 20 g/L and 30 g/L. Proliferation of KCs in each group was measured using Ki67 staining flow cytometry. Apoptosis was measured using Annexin V-FITC/PI double staining flow cytometry. KCs were divided into three groups according to the source of the exosomes they were cultured with: patients with AD, healthy controls and blank controls. Q-PCR was used to detect the activation (K6) and differentiation (K10) of cells, as well as inflammatory indicators (thymic stromal lymphopoietin (TSLP) and IL-33).ResultsThe proliferation rate of KCs treated with 20 g/L exosomes from AD patients was significantly lower than that of other groups, while the apoptosis rate was significantly increased. Additionally, expression levels of K6, K10, TSLP and IL-33 were all up-regulated compared to keratinocytes treated with exosomes from healthy controls.ConclusionExosomes from the peripheral blood of pediatric AD patients can regulate the activation, apoptosis and inflammatory cytokine secretion of KCs in vivo, which may participate in the pathogenesis of AD.

P05-06 Protective role of peroxiredoxin V against UVB-induced apoptosis of epidermal keratinocytes

P05-06 Protective role of peroxiredoxin V against UVB-induced apoptosis of epidermal keratinocytes

Adult-onset Still's disease: A disease at the crossroad of innate immunity and autoimmunity.

Adult-onset Still’s disease (AOSD) is a rare disease affecting multiple systems and organs with unknown etiology, and the clinical symptoms are usually described as spiking fever, arthritis, evanescent salmon-pink eruptions, lymphadenopathy, splenomegaly, and other manifestations. The laboratory indicators are not specific, often presenting as increased leukocyte counts and neutrophil percentage, elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), hyperferritinemia, and increased inflammatory factors. ANA, ENA, and RF are negative. According to those unspecific clinical presentations and laboratory findings, infection, tumor, connective tissue disease, and other diseases must be ruled out before diagnosis. The diagnosis of AOSD is a great challenge for clinicians. The mechanism of AOSD pathogenesis is complicated and still being studied. There is a new opinion that atypical persistent skin eruptions (APSEs) with specific histological manifestations are unique for AOSD, and APSEs might be on a spectrum with classical evanescent eruptions. Studies on APSEs showed that IL-1β and IFN-γ are strongly correlated with the pathogenesis of necrosis keratinocytes in APSEs. IL-1β is strongly involved in inflammatory disease when it is abnormal, and plays an important role in the pathogenesis of neutrophil dermatosis. In the early stage of AOSD, skin lesions appear to be evanescent urticaria-like eruptions accompanied by fever, and only neutrophils infiltrate around the blood vessels in the dermis pathologically. As the course of the disease progresses, IL-1β is gradually released. Through the stimulation of other inflammatory factors and the influence of unknown factors, IL-1β gradually infiltrates into the stratum corneum and finally accumulates around the necrotic keratinocytes of the stratum corneum. However, the detailed mechanism is still unknown. IFN-γ could play a pro-inflammatory or regulatory role in some disorders. IL-1β can enhance the expression of IFN-γ, and IFN-γ can cause keratinocyte apoptosis by activating the autocrine of caspase. Also, several pieces of evidence indicate that adaptive immunity is also involved in the pathogenesis of AOSD. Increased α-soluble receptors of IL-2 may suggest T-cell activation and proliferation in AOSD patients. Increased IL-4- and IFN-γ-producing T cells were found in active AOSD and related to disease severity. Frequencies of Treg cells in AOSD were significantly lower and were inversely correlated with disease severity. According to these, more and more researchers have reached a consensus that AOSD is a disease at the crossroads of innate immunity and autoimmunity. In this review, we will provide a comprehensive insight into AOSD, describing research progress and the immunological mechanism contribution to the disease. In the meantime, different treatment options and the efficacy and safety of various biologic agents are also discussed. A further understanding of AOSD requires closer cooperation among doctors from different departments, and this review will provide a new idea for diagnosis and therapeutic options.

IL-15/IL-15Rα in SJS/TEN: Relevant Expression of IL15 and IL15RA in Affected Skin.

Stevens–Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a life-threatening hypersensitivity reaction to medications characterized by keratinocyte apoptosis and skin detachment. IL-15 serum levels have been associated with severity and prognosis of SJS/TEN. We have measured IL-15 concentrations in serum and blister fluid (BF) from patients with SJS/TEN by ELISA and used quantitative RT-PCR to analyze the expression of IL15 and IL15RA (encoding for IL-15 Receptor-α chain) genes in peripheral blood and BF cells, including isolated monocytes, and in affected skin. A positive correlation was found between IL-15 serum levels and a percent of detached skin. BF concentrations were higher, but no correlation was found. Higher IL15 and IL15RA gene expression levels were found in skin-infiltrating blister fluid cells compared to peripheral mononuclear cells. Moreover, IL15RA transcripts were barely detected in healthy skin, being the highest expression levels found in samples from two SJS/TEN patients who did not survive. The cutaneous expression of IL-15Rα in SJS/TEN may provide an explanation to the tissue-specific immune cytotoxic response in this clinical entity, and the results suggest that the effects of IL-15 in SJS/TEN patients may be dependent on the expression of its private receptor IL-15Rα in affected skin.

Pigmented squamous cell carcinoma in situ with amyloid deposition mimicking melanoma

Pigmented squamous cell carcinoma in situ with amyloid deposition mimicking melanoma

Histatin-1 alleviates high-glucose injury to skin keratinocytes through MAPK signaling pathway.

Damage to keratinocytes and other skin cells in a high-glucose environment has been proven to be an important reason for the poor wound healing ability of chronic diabetes mellitus. Histatin-1 has been preliminarily proven to stimulate the wound healing process of the oral and non-oral mucosa and has been found to be related to the activation of extracellular signal-regulated kinase (ERK). The purpose of this study was to investigate the effect of histatin-1 on high-glucose-injured keratinocytes and the role of the Ras-Raf-MEK-ERK signaling pathway on the effect of histatin-1 to improve diabetic wound healing. A human keratinocyte model damaged by high glucose was constructed, cell proliferation was detected by the Cell Counting Kit-8 assay, and cell apoptosis was detected by flow cytometry. The expression level of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was detected by ELISA, and the mitogen-activated protein kinase (MAPK) signaling pathway protein expression level was detected by Western blot. C-fos mRNA expression was detected by real-time PCR. The results indicated that histatin-1 promoted proliferation and reduced the rate of apoptosis and 8-OHdG content in keratinocytes with high-glucose injury. In addition, histatin-1 down-regulated MEK phosphorylation in keratinocytes with high-glucose injury. However, with the extension of the intervention, the effect of histatin-1 on c-fos mRNA expression was different. At the early stage of high-glucose injury (12 h), the expression of c-fos mRNA was not increased in high-glucose-injured keratinocytes treated with histatin-1 but then c-fos mRNA expression was gradually upregulated. Histatin-1 could alleviate keratinocyte injury caused by high glucose levels and promoted wound healing in vitro. In addition, histatin-1 could exert anti-apoptotic and antioxidant damage effects under high-glucose injury states. These effects of histatin-1 may be related to its regulation of the MAPK signaling pathway. Therefore, these findings provide an essential theoretical basis for histatin-1 to become a safe and effective new peptide biological agent to promote wound healing in patients with diabetes.