Molecular Insights Into the Effects of PLLA-SCA on Gene Expression and Collagen Synthesis in Human 3D Skin Models Containing Macrophages

Injectable poly-L-lactic acid (PLLA-SCA) is used for the correction of shallow to deep nasolabial fold contour deficiencies, cheek wrinkles, and other facial wrinkles. In contrast to hyaluronan (HA) fillers, PLLA-SCA has a biostimulatory effect by activating resident fibroblasts to produce collagen, but the mechanisms are not known in detail at the molecular level. Therefore, our aim was to investigate the molecular effects of PLLA-SCA in a comprehensive in vitro study. Since PLLA-SCA-dependent collagen production in fibroblasts depends on the interaction with macrophages, we generated novel macrophage-containing 3D skin models. According to the clinical application, PLLA-SCA was injected once into the dermal equivalent of the 3D skin model. Histological analysis showed a significant increase in epidermal thickness in these models after 5 and 14 days. Gene expression profiling revealed an upregulation of integrins and laminins (e.g., LAMA3, ITGA6), which are essential components of the dermal-epidermal junction. In addition, we found an upregulation of cytokines and chemokines (TGFB2, CXCL6, IL1B) at day 14 after PLLA-SCA injection. Interestingly, immunohistochemical analyses exhibited a significantly stimulated collagen I production in our models. These effects might be attributed, at least in part, to the upregulation of IL1B and subsequently CXCL6, which stimulates collagen I synthesis in human dermal fibroblasts as we could demonstrate. Taken together, our data provide for the first time molecular insights into the biostimulatory effects of PLLA-SCA on collagen I production in novel human 3D skin models comprising macrophages. J Drugs Dermatol. 2024;23(4):7791.    doi:10.36849/JDD.7791.

Macrophage-like rapid uptake and toxicity of tattoo ink in human monocytes

Macrophages play a critical role for the persistence of tattoo ink in human skin. However, a comparison to other skin-resident and blood circulating immune cells and a profound analysis of REACH-compliant tattoo ink are unmet medical needs. We hence characterized the size distribution of ink particles using physicochemical methods. We studied the uptake of tattoo ink by key human skin cells and blood-derived immune cells using optical and electron microscopy as well as flow cytometry. Scanning electron microscopy of ink revealed its crystalline structure, and a tendency towards aggregations was indicated by size changes upon diluting it. Flow cytometric analyses of skin and immune cells after incubation with tattoo ink demonstrated an increase in cellular granularity upon uptake and red ink additionally evoked fluorescent signals. Human macrophages were most potent in internalizing ink in full thickness 3D skin models. Macrophage cultures demonstrated that the ink did not lead to elevated inflammatory mediators, and showed no indications for toxicity, even after nice days. Strikingly, monocytes were most efficient in ink uptake, but displayed reduced viability, whereas granulocytes and lymphocytes showed only temporary ink uptake with flow cytometric signals declining after 1 day. Mechanistic studies on ink retention by corticosteroids or dexpanthenol in macrophage cultures demonstrated that these compounds do not lead to ink excretion, but even slightly increase the ink load in macrophages. The highly motile monocytes, precursors of macrophages, may play an underrated role for tattoo ink translocation from dermal blood vessels into internal organs.

Pathological mutations reveal the key role of the cytosolic iRhom2 N-terminus for phosphorylation-independent 14-3-3 interaction and ADAM17 binding, stability, and activity

The protease ADAM17 plays an important role in inflammation and cancer and is regulated by iRhom2. Mutations in the cytosolic N-terminus of human iRhom2 cause tylosis with oesophageal cancer (TOC). In mice, partial deletion of the N-terminus results in a curly hair phenotype (cub). These pathological consequences are consistent with our findings that iRhom2 is highly expressed in keratinocytes and in oesophageal cancer. Cub and TOC are associated with hyperactivation of ADAM17-dependent EGFR signalling. However, the underlying molecular mechanisms are not understood. We have identified a non-canonical, phosphorylation-independent 14-3-3 interaction site that encompasses all known TOC mutations. Disruption of this site dysregulates ADAM17 activity. The larger cub deletion also includes the TOC site and thus also dysregulated ADAM17 activity. The cub deletion, but not the TOC mutation, also causes severe reductions in stimulated shedding, binding, and stability of ADAM17, demonstrating the presence of additional regulatory sites in the N-terminus of iRhom2. Overall, this study contrasts the TOC and cub mutations, illustrates their different molecular consequences, and reveals important key functions of the iRhom2 N-terminus in regulating ADAM17.

Understanding the impact of risankizumab on keratinocyte-derived IL-23A in a novel organotypic 3D skin model containing IL-23A responsive and IL-17A producing γδ-T-cells

PURPOSE

To study the effects of the anti-IL-23A antibody risankizumab on the IL-36γ/IL-23A/IL-17A signalling cascade we used a newly developed 3D skin model consisting of primary human keratinocytes, fibroblasts and γδ-T-cells.

METHODS

In this in vitro study we developed new full-thickness 3D skin models containing normal human epidermal keratinocytes (NHEK), normal human dermal fibroblasts (NHDF) and IL-23A responsive and IL-17A producing γδ-T-cells. The effects of IL-36γ stimulation with and without risankizumab treatment on IL-23A and IL-17A expression were examined at the RNA and protein levels.

RESULTS

In preliminary monolayer experiments stimulation of γδ-T-cells with IL-23A promoted the IL-17A expression that was inhibited after risankizumab treatment. Using 3D skin models containing γδ-T-cells, we found that stimulation with IL-36γ significantly increased not only IL-23A but also IL-17A expression. These effects were inhibited by concomitant treatment with risankizumab.

CONCLUSIONS

Our results showed that blockade of IL-23A has inhibitory effects on the IL-36γ/IL-23A feedforward loop. Our newly developed 3D skin model containing IL-23A responsive and IL-17A producing γδ-T-cells enables molecular analysis of targeted therapies aimed at the IL-36γ/IL-23A/IL-17A signalling cascade in psoriasis.

Macrophage migration inhibitory factor (MIF) and its homolog D-dopachrome tautomerase (D-DT) are significant promotors of UVB- but not chemically induced non-melanoma skin cancer

Non-melanoma skin cancer (NMSC) is the most common cancer in Caucasians worldwide. We investigated the pathophysiological role of MIF and its homolog D-DT in UVB- and chemically induced NMSC using Mif-/-, D-dt-/- and Mif-/-/D-dt-/- mice on a hairless SKH1 background. Knockout of both cytokines showed similar attenuating effects on inflammation after acute UVB irradiation and tumor formation during chronic UVB irradiation, without additive protective effects noted in double knockout mice, indicating that both cytokines activate a similar signaling threshold. In contrast, genetic deletion of Mif and D-dt had no major effects on chemically induced skin tumors. To get insight into the contributing mechanisms, we used an in vitro 3D skin model with incorporated macrophages. Application of recombinant MIF and D-DT led to an accumulation of macrophages within the epidermal part that could be reversed by selective inhibitors of MIF and D-DT pathways. In summary, our data indicate that MIF and D-DT contribute to the development and progression of UVB- but not chemically induced NMSC, a role at least partially accounted by effects of both cytokines on epidermal macrophage accumulation. These data highlight that MIF and D-DT are both potential therapeutic targets for the prevention of photocarcinogenesis but not chemical carcinogenesis.

Therapy of pathological scars

A scar develops following the appearance of a deep tissue defect as part of the physiological wound healing process. The initial inflammatory response is followed by proliferation of connective tissue cells, which form fibrosis as a final tissue substitute. Disorders can occur at all stages of the process and are most commonly manifested as impaired wound healing or the formation of atrophic and hypertrophic scars or keloids. The focus of this article is on the treatment of pathologic scars, which are an indication for therapy due to functional limitations, complaints, and stigmatization, among other reasons. Conservative medical, physical, surgical and laser therapeutic approaches are pursued. The basis for this is an understanding of the pathophysiological mechanisms and factors influencing the choice of therapy, as well as an interdisciplinary and interprofessional therapeutic approach.

Post-Treatment of Micro-Needling with a Dexpanthenol-Containing Ointment Accelerates Epidermal Wound Healing in Human 3D Skin Models

Purpose

In vitro study on the molecular effects of post-treatment after micro-needling applications with a dexpanthenol-containing ointment (DCO) using 3D skin models.

Patients and Methods

In this in vitro study, full-thickness human 3D skin models were treated with a micro-needling device according to its clinical application. For post-treatment, some of the models were additionally treated with a dexpanthenol-containing ointment (DCO). Histological samples were taken at 0, 24 and 48 hours. Gene expression analysis was performed after 24 hours.

Results

Histological examination showed that DCO post-treated 3D skin models revealed a completed wound closure 24 hours after the micro-needling procedure. In contrast, DCO-untreated models still clearly exhibited the micro-needling lesions after the same period of time. After 48 hours, all models revealed a completed wound healing. In skin models that received micro-needling but no post-treatment with DCO, microarray analysis identified an upregulation of proinflammatory cytokines and chemokines and a downregulation of skin barrier and differentiation markers. In contrast, post-treatment with DCO leads to accelerated wound healing without affecting the initial inflammatory response caused by micro-needling, which leads to the subsequent collagen expression. This data was supported by qRT-PCR analyses.

Conclusion

Post-treatment with DCO accelerates epidermal wound healing after micro-needling of 3D skin models without impairing the immunostimulatory properties of micro-needling. These findings can help to optimise the aftercare routine after micro-needling procedures and to shorten the downtime for the patient after treatment.

S2k guideline: Laser therapy of the skin

This guideline aims to improve the efficiency and safety of lasers and optical radiation sources with similar effects (especially IPL). Laser therapy of skin lesions with an increased amount of melanocytes should be performed with caution. Laser treatment of pigmented melanocytic nevi is not recommended. The guideline contains recommendations regarding the treatment of lentigines and café-au-lait spots, non-pigmented dermal nevi, Becker nevus, nevus of Ota/Hori/Ito and melasma. Further recommendations focus on the treatment of skin lesions without an increased amount of melanocytes (ephelides, postinflammatory hyperpigmentation including berloque dermatitis, seborrheic keratoses, traumatic/decorative tattoos and metallic deposits), hypopigmentation (vitiligo), benign non-pigmented neoplasms (fibrous papule of the nose, nevus sebaceus, epidermal nevus, neurofibroma, sebaceous gland hyperplasia, syringoma, xanthelasma palpebrarum), inflammatory dermatoses (acne papulopustulosa/conglobata, acne inversa, granuloma faciale, lichen sclerosus, lupus erythematosus, psoriasis vulgaris, rosacea, rhinophyma), wrinkles/dermatochalasis/striae, hypertrichosis, scars (atrophic, hypertrophic; keloids, burn/scald scars), laser-assisted skin healing, onychomycosis, precancerous lesions and malignant tumors (actinic keratoses/field cancerization, cheilitis actinica, basal cell carcinoma), vascular skin lesions (angiokeratoma, angioma, hemangioma, malformation, spider veins, granuloma telangiectaticum (pyogenic granuloma), rubeosis (erythrosis interfollicularis colli, ulerythema ophryogenes), nevus flammeus, telangiectasias and Osler's disease (hereditary hemorrhagic telangiectasia) and viral skin lesions (condylomata acuminata, mollusca contagiosa, verrucae planae juveniles/vulgares/ verrucae palmares et plantares).

Innate immune activation as cofactor in pemphigus disease manifestation

Molecular mechanisms underlying auto-antibody-induced acantholysis in pemphigus vulgaris are subject of current research to date. To decipher the discrepancy between ubiquitous antibody binding to the epidermal desmosomes, but discontinuous disease manifestation, we were able to identify Ultraviolet A (UVA) as a cofactor for acantholysis. UVA induces interleukin (IL)-1 secretion in keratinocytes, mirroring innate immune system activation. In an in vitro keratinocyte dissociation assay increased fragmentation was observed when UVA was added to anti-Desmoglein 3 Immunoglobulins (anti-Dsg3 IgG). These results were confirmed in skin explants where UVA enhanced anti-Dsg3-mediated loss of epidermal adhesion. The UVA-mediated effect was blocked in vitro by the pan-caspase-inhibitor zVAD-fmk. Thus, we introduce UVA as a caspase-dependent exogenous cofactor for acantholysis which suggests that local innate immune responses largely contribute to overt clinical blister formation upon autoantibody binding to epidermal cells in pemphigus vulgaris.

Management of patients with seasonal allergic rhinitis: Diagnostic consideration of sensitization to non-frequent pollen allergens

BACKGROUND

Diagnosis of pollen allergies is mainly based on test allergens for skin prick testing. In the minimum battery of test inhalant allergens recommended by the Global Allergy and Asthma European Network 10 pollen allergens are included. Complementary other pollen allergens may need to be considered; however, respective awareness may not always be granted. Furthermore, at least in Germany, the situation may be even more complicated by the fact that test allergens need regulatory approval. A decline in commercially available test allergens may result in a diagnostic gap regarding patients with non-frequent allergies. How many patients with non-frequent pollen allergies would be affected by this gap? The data presented here partly answer this question.

METHODS

The study consisted of a descriptive and an analytical part. In the descriptive part, sensitization to frequent pollen allergens (alder, hazel, birch, sweet grasses; according to the German Therapy Allergen Ordinance) and to respective non-frequent pollen allergens (cypress, Japanese cedar, ash, plane tree, olive, Bermuda grass, wall pellitory, plantain, goosefoot, mugwort, ragweed, and saltwort) was measured in adult patients with physician-diagnosed allergic rhinitis from two German federal states, namely North-Rhine Westphalia (n = 360) and Bavaria (n = 339), using skin prick testing and/or ISAC technology. Furthermore, respective regional pollen data were assessed. In the analytical part, sensitization data were correlated with each other and with anamnestic data on symptom periods.

RESULTS

Sensitization to frequent pollen allergens ranged from 45% (sIgE to Aln g 1/Alder, NRW) to 72% (prick test reactivity to birch, NRW). Sensitization to non-frequent pollen allergens ranged from 0% (sIgE to Amb a 1/ragweed, NRW) to 41% (prick test reactivity to olive, Bavaria). Sensitization data partly correlated with each other and in connection with symptom periods showed a partly similar seasonal pattern as pollen data.

CONCLUSIONS

Sensitization to non-frequent pollen allergens have to be considered when examining patients with respective seasonal symptoms, and test (and respective therapy) allergens for non-frequent pollen allergies need to be available. Further prerequisites for adequate patient management would be a nationwide pollen monitoring system giving continuous pollen data and a systematic sensitization monitoring at patient level.

Molecular effects of photon irradiation and subsequent aftercare treatment with dexpanthenol-containing ointment or liquid in 3D models of human skin and non-keratinized oral mucosa

This study aimed to investigate the molecular effects of radiation and subsequent aftercare treatment with dexpanthenol-containing ointment and liquid on established full-thickness 3D skin models depicting acute radiodermatitis and mucositis. To mimic radiomucositis and radiodermatitis, non-keratinized mucous membrane and normal human skin models were irradiated with 5 Gray. Afterwards, models were treated topically every second day with dexpanthenol-containing ointment or liquid in comparison with placebo and untreated controls. On day 7 after irradiation, histological examination showed impairments in irradiated models. In contrast, models treated with dexpanthenol-containing ointment or liquid showed a completely restored epidermal part. While gene expression profiling revealed an induction of genes related to a pro-inflammatory milieu, oxidative stress and an impaired epidermal differentiation after irradiation of the models, aftercare treatment with dexpanthenol-containing ointment or liquid revealed anti-oxidative and anti-inflammatory effects and had a positive effect on epidermal differentiation and structures important for physical and antimicrobial barrier function. Our findings confirm the potential of our established models as in vitro tools for the replacement of pharmacological in vivo studies regarding radiation-induced skin injuries and give indications of the positive effects of dexpanthenol-containing externals after radiation treatments as part of supportive tumor treatment.

Metabolic activation and toxicological evaluation of polychlorinated biphenyls in Drosophila melanogaster

Degradation of polychlorinated biphenyls (PCBs) is initiated by cytochrome P450 (CYP) enzymes and includes PCB oxidation to OH-metabolites, which often display a higher toxicity than their parental compounds. In search of an animal model reflecting PCB metabolism and toxicity, we tested Drosophila melanogaster, a well-known model system for genetics and human disease. Feeding Drosophila with lower chlorinated (LC) PCB congeners 28, 52 or 101 resulted in the detection of a human-like pattern of respective OH-metabolites in fly lysates. Feeding flies high PCB 28 concentrations caused lethality. Thus we silenced selected CYPs via RNA interference and analyzed the effect on PCB 28-derived metabolite formation by assaying 3-OH-2',4,4'-trichlorobiphenyl (3-OHCB 28) and 3'-OH-4',4,6'-trichlorobiphenyl (3'-OHCB 28) in fly lysates. We identified several drosophila CYPs (dCYPs) whose knockdown reduced PCB 28-derived OH-metabolites and suppressed PCB 28 induced lethality including dCYP1A2. Following in vitro analysis using a liver-like CYP-cocktail, containing human orthologues of dCYP1A2, we confirm human CYP1A2 as a PCB 28 metabolizing enzyme. PCB 28-induced mortality in flies was accompanied by locomotor impairment, a common phenotype of neurodegenerative disorders. Along this line, we show PCB 28-initiated caspase activation in differentiated fly neurons. This suggested the loss of neurons through apoptosis. Our findings in flies are congruent with observation in human exposed to high PCB levels. In plasma samples of PCB exposed humans, levels of the neurofilament light chain increase after LC-PCB exposure, indicating neuronal damage. In summary our findings demonstrate parallels between Drosophila and the human systems with respect to CYP mediated metabolism and PCB mediated neurotoxicity.

Biological Effects of Hyaluronic Acid-Based Dermal Fillers and Laser Therapy on Human Skin Models

Injection of dermal fillers is one of the most frequently performed aesthetic procedures. The aim of the present study was to investigate the biological effects of different stabilized hyaluronan (HA) and poly-l-lactic acid fillers with and without subsequent additional fractional laser co-treatment on skin morphology and gene expression. Intradermal injection resulted in a significant enhancement of epidermal thickness detected by histological analysis. Combining HA fillers with ablative fractional CO2- or Er:YAG laser irradiation enhanced this effect. Gene expression profiling revealed an upregulation of modulators of tissue remodeling (eg TIMP3, SERPIN E1) and collagens (COL11A1). On the other hand, we detected a downregulation of differentiation markers (eg FLG, LOR, KRT1) and proinflammatory cytokines (eg IL-36, IL-1β). Interestingly, HA-based fillers revealed a specific upregulation pattern of chemokines such as CXCL5 andCCL20 suggesting a secondary effect of these fillers on the immune cells of the skin, especially monocytes and macrophages. Taken together, our data show enhancing effects of dermal fillers on epidermal thickness and prove the proliferating effects of these products on epidermal cells on the molecular level. Moreover, our findings reveal synergistic effects of fractional ablative laser treatment and HA dermal filler injection suggesting a combination of both treatments. J Drugs Dermatol. 2020;19(9):897-899. doi:10.36849/JDD.2020.4856.

Biological Effects of Hyaluronic Acid-Based Dermal Fillers and Laser Therapy on Human Skin Models

Injection of dermal fillers is one of the most frequently performed aesthetic procedures. The aim of the present study was to investigate the biological effects of different stabilized hyaluronan (HA) and poly-l-lactic acid fillers with and without subsequent additional fractional laser co-treatment on skin morphology and gene expression. Intradermal injection resulted in a significant enhancement of epidermal thickness detected by histological analysis. Combining HA fillers with ablative fractional CO2- or Er:YAG laser irradiation enhanced this effect. Gene expression profiling revealed an upregulation of modulators of tissue remodeling (eg TIMP3, SERPIN E1) and collagens (COL11A1). On the other hand, we detected a downregulation of differentiation markers (eg FLG, LOR, KRT1) and proinflammatory cytokines (eg IL-36, IL-1β). Interestingly, HA-based fillers revealed a specific upregulation pattern of chemokines such as CXCL5 andCCL20 suggesting a secondary effect of these fillers on the immune cells of the skin, especially monocytes and macrophages. Taken together, our data show enhancing effects of dermal fillers on epidermal thickness and prove the proliferating effects of these products on epidermal cells on the molecular level. Moreover, our findings reveal synergistic effects of fractional ablative laser treatment and HA dermal filler injection suggesting a combination of both treatments. J Drugs Dermatol. 2020;19(9):897-899. doi:10.36849/JDD.2020.4856.

Inter-α-Trypsin Inhibitor Heavy Chain 5 (ITIH5) Is a Natural Stabilizer of Hyaluronan That Modulates Biological Processes in the Skin

INTRODUCTION

Hyaluronan (HA) is a major component of the skin that exerts a variety of biological functions. Inter-α-trypsin inhibitor heavy chain (ITIH) proteins comprise a family of hyaladherins of which ITIH5 has recently been described in skin, where it plays a functional role in skin morphology and inflammatory skin diseases including allergic contact dermatitis (ACD).

OBJECTIVE

The current study focused on the ITIH5-HA interaction and its potential clinical and functional impact in extracellular matrix (ECM) stabilization.

METHODS

Studying the molecular effects of ITIH5 in skin, we established skin models comprising murine skin cells of Itih5 knockout mice and corresponding wild-type controls. In addition, human dermal fibroblasts with an ITIH5 knockdown as well as a murine recombinant Itih5 protein were established to examine the interaction between ITIH5 and HA using in vitro adhesion and HA degradation assays. To understand more precisely the role of ITIH5 in inflammatory skin diseases such as ACD, we generated ITIH5 knockout cells of the KeratinoSens® cell line.

RESULTS

Using murine skin models, ITIH5 knockdown fibroblasts, and a reactive oxygen species (ROS)-mediated HA degradation assay, we proved that ITIH5 binds to HA, thereby acting as a stabilizer of HA. Moreover, microarray profiling revealed the impact of ITIH5 on biological processes such as skin development and ECM homeostasis. Performing the in vitro KeratinoSens skin sensitization assay, we detected that ITIH5 decreases the sensitizing potential of moderate and strong contact sensitizers.

CONCLUSION

Taken together, our experiments revealed that ITIH5 forms complexes with HA, thereby on the one hand stabilizing HA and facilitating the formation of ECM structures and on the other hand modulating inflammatory responses.

Dexpanthenol in Wound Healing after Medical and Cosmetic Interventions (Postprocedure Wound Healing)

With the availability of new technologies, the number of subjects undergoing medical and cosmetic interventions is increasing. Many procedures (e.g., ablative fractional laser treatment) resulting in superficial/minor wounds require appropriate aftercare to prevent complications in wound healing and poor cosmetic outcome. We review the published evidence of the usefulness of topical dexpanthenol in postprocedure wound healing and the associated mechanisms of action at the molecular level. A search in the PubMed and Embase databases was performed to query the terms dexpanthenol, panthenol, superficial wound, minor wound, wound healing, skin repair, and postprocedure. Search results were categorized as clinical trials and in vitro studies. In vitro and clinical studies provided evidence that topically applied dexpanthenol promotes superficial and postprocedure wound healing. Latest findings confirmed that dexpanthenol upregulates genes that are critical for the healing process. The gene expression data are of clinical relevance as evidenced by prospective clinical studies indicating that topical dexpanthenol accelerates wound healing with rapid re-epithelialization and restoration of skin barrier function following skin injury. It can therefore be inferred that topical dexpanthenol represents an appropriate and state-of-the-art treatment option for superficial postprocedure wounds, especially when applied early after the superficial skin damage.

Optimal Support of Wound Healing: New Insights

BACKGROUND

The ultimate goal of wound healing following minor injury is to form a tissue regenerate that has functionality and visual appearance as close to the original skin as possible. The body's physiological response to any wound is traditionally characterised by three distinct steps: inflammation, proliferation and remodelling.

SUMMARY

New insights suggest that the three phases overlap (and even occur in parallel) in both time and space in the wound, necessitating a clinical approach that targets each stage simultaneously to ensure rapid repair and wound closure without further complications. Ingredients that exhibit activity across each of the three phases, such as dexpanthenol, are of value in the context of minor wound care and scar management. Key Messages: In addition to treatment and ingredient selection, it is also important to consider broader clinical best practices and self-care options that can be used to optimise the management of minor wounds. An individualised approach that can account for a patient's unique requirements and preferences is critical in achieving effective wound recovery.

Bifonazole Exerts Anti-Inflammatory Effects in Human Three-Dimensional Skin Equivalents after UVB or Histamine Challenge

BACKGROUND

In addition to its role as a broad-spectrum imidazole antifungal drug, data from animal models as well as human clinical trials also demonstrated an anti-inflammatory efficacy of bifonazole (BFZ). In the histamine wheal test and after UV radiation, BFZ showed antiphlogistic effects that were comparable to those of hydrocortisone. However, the underlying molecular mechanisms of the anti-inflam-matory properties of BFZ are poorly understood.

METHODS

Performing an in vitro study we used full-thickness three-dimensional (3D) skin models containing macrophages as mediators of inflammation. We conducted two sets of experiments. In a first set we exposed our models to UVB irradiation to provoke an inflammation. A second approach used the addition of histamine into the culture medium. In both approaches, models were treated topically with a BFZ-containing ointment or a placebo ointment for 24 h, and then the effects were examined histologically as well as with microarray and quantitative real-time PCR analyses.

RESULTS

Histological examination showed that the BFZ-containing ointment reconstituted UVB- and histamine-mediated disorders within the skin models. Performing gene expression profiling in models that were treated with the BFZ-containing ointment after UVB irradiation, we detected an upregu-lation of differentiation markers (fillagrin, loricrin, and keratin 1), antimicrobial peptides (DEFB103A), and members of the cytochrome P450 family (CYP1A1 and CYP1B1) as well as a downregulation of genes that are involved in immune response (CCL22, CXCL12, CCL7, IRF1, ICAM1, TLR3, and RARRES3) and matrix metalloproteinases (MMP12 and MMP7). Models that were treated with the BFZ-containing ointment after histamine application showed an upregulation of members of the cytochrome P450 family (CAP1A1, CYP1B1, and CYP24A1) and a downregulation of immune response-associated genes (CXCL6, CXCL12, CCL8, IL6, and IL32).

CONCLUSION

We present the first in vitro study showing anti-inflammatory effects of BFZ in human 3D skin models. To our knowledge, this is the first time that these effects could be translated from human clinical trials into an in vitro test system, allowing a more detailed examination of molecular mechanisms that were regulated by BFZ.

Novel Human Full-Thickness Three-Dimensional Nonkeratinized Mucous Membrane Model for Pharmacological Studies in Wound Healing

INTRODUCTION

Efforts are increasingly aiming to develop in vitro models that can provide effective alternatives to in vivo experiments. The main aim of this study was the establishment of an in vitro model of the nonkeratinized mucous membrane that can be used as a standardized tool to evaluate biological and therapeutic effects of pharmaceuticals for mucosal wound healing.

METHODS

We established a full-thickness in vitro model of the nonkeratinized mucous membrane. While histological examination was performed to assess morphological characteristics, we utilized gene expression profiling using microarray and qRT-PCR analyses to identify molecular effects of treatment with a dexpanthenol-containing ointment after laser wounding.

RESULTS

Performing histological and immunofluorescence analyses we proved that our model mimics the two distinctive layers of the mucous membrane - the stratified squamous epithelium and the lamina propria. We used this model to investigate molecular effects of a dexpanthenol-containing ointment that is commonly used for the wound treatment of mucous membranes. For that purpose, our model exhibits a unique feature in that dexpanthenol and proliferation-enhancing additives that may interfere with our studies are not required for the maintenance of the model culture. After setting standardized lesions with a nonsequential fractional ultrapulsed CO2 laser, topical treatment with the dexpanthenol-containing ointment enhanced wound closure in the model compared to placebo and untreated controls. Furthermore, microarray analysis revealed that the treatment of the laser-wounded model with the dexpanthenol-containing ointment evoked an upregulated expression of various genes related to accelerated wound healing.

CONCLUSION

Overall, we verified that this novel mucous membrane model can be utilized in future to monitor ex vivo effects of various topical therapies on mucosa morphology, physiology, and gene expression. Our findings confirm the potential of the model as an in vitro tool for the replacement of pharmacological in vivo studies regarding mucosal wound healing.

Four-year follow-up of two patients on maintenance therapy with fondaparinux and mycophenolate mofetil for microthrombotic antiphospholipid syndrome

Objectives

We discuss two patients with antiphospholipid syndrome (APS) who presented with critical ischemia of both lower extremities due to arterial microthrombi. They received multimodality therapy emergently: anticoagulation, immunosuppression, and therapeutic plasma exchange (TPE). Then they were maintained on anticoagulation with fondaparinux and immunosuppression with mycophenolate mofetil (MMF), and were followed for 4 years.

Methods

Two patients with APS with ischemia and necrosis of their distal lower extremities were treated emergently with anticoagulation (intravenous heparin), immunosuppression (prednisone), and TPE. They were maintained on anticoagulation with fondaparinux and immunosuppression with MMF.

Results

Neither patient had recurrent microthrombotic disease during a 4-year follow-up.

Conclusions

As described in our small cohort, patients with APS who suffer from microthrombotic arterial disease may benefit from maintenance therapy of anticoagulation with fondaparinux and immunosuppression with MMF, an approach which may be worthy of further trial. Fondaparinux does not require attention to diet, monitoring, and cumbersome bridging that is typical of warfarin therapy. MMF provides immunosuppression while sparing the side effects of steroid treatment.

Accelerated wound healing with a dexpanthenol-containing ointment after fractional ablative CO2 laser resurfacing of photo-damaged skin in a randomized prospective clinical trial

Background: Laser therapy with an ablative CO₂ laser is a prominent treatment option for photo-damaged skin. The healing process and therefore the success of a laser can be supported by an appropriate postoperative treatment of the laser-treated skin. Objective: The effect of a dexpanthenol-containing ointment with petroleum jelly on wound healing after fractional ablative CO₂ laser therapy of photo-damaged skin. Methods: A total of 38 patients with photo-damaged skin received fractional ablative CO₂ laser treatment. Occlusive wound care was conducted for a period of 7 days. The complete wound area was divided into two sections: one that was treated with a dexpanthenol-containing ointment and a section that was treated with petroleum jelly. This study had three primary outcome measures: (1) Overview images as well as dermatoscopic images of the laser treated skin were taken immediately after laser treatment and on days 1, 2, 5 and 14 (study visits). Dermatoscopic images were analysed to determine changes of the diameter of the individual lesions between the study visits. (2) Wound-healing rate was visually assessed, based on the measure of re-epithelialization. (3) Cosmetic results were evaluated during study visits by patients and physicians applying a visual analogue scale (VAS). Results: Measuring the diameter of laser-generated lesions revealed a significantly faster cure of the lesions in wound sections that were treated with the dexpanthenol-containing ointment on days 1 and 2, in comparison to the lesions that were treated with petroleum jelly. Concordantly, visual evaluation of the wounds revealed significantly better cosmetic results and re-epithelialization on days 1, 2 and 5 after laser treatment in wound sites that were treated with the dexpanthenol-containing ointment. All patients exhibited a completed wound healing on day 14 after laser treatment. Conclusion: In this comparative study, post-operative treatment of laser-treated skin with a dexpanthenol-containing ointment led to a significantly faster wound closure in comparison to petroleum jelly, especially during the early phase of wound healing. Moreover, assessment of the cosmetic result exhibited beneficial effects of the dexpanthenol-containing ointment in the post-operative wound care after laser treatment. These results emphasize that the use of a dexpanthenol-containing ointment in the post-operative phase following CO2 laser therapy could be a promising alternative to the routinely used treatment with petroleum jelly.

Macrophages significantly enhance wound healing in a vascularized skin model

Tissue-engineered dermo-epidermal skin grafts could be applied for the treatment of large skin wounds or used as an in vitro wound-healing model. However, there is currently no skin replacement model that includes both, endothelial cells to simulate vascularization, and macrophages to regulate wound healing and tissue regeneration. Here, we describe for the first time a tissue-engineered, fully vascularized dermo-epidermal skin graft based on a fibrin hydrogel scaffold, using exclusively human primary cells. We show that endothelial cells and human dermal fibroblasts form capillary-like structures within the dermis whereas keratinocytes form the epithelial cell layer. Macrophages played a key role in controlling the number of epithelial cells and their morphology after skin injury induced with a CO₂ laser. The activation of selected cell types was confirmed by mRNA analysis. Our data underline the important role of macrophages in vascularized skin models for application as in vitro wound healing models or for skin replacement therapy. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1340-1350, 2019.

Individual risk assessment in the diagnosis of immediate type drug hypersensitivity reactions to betalactam and non-betalactam antibiotics using basophil activation test: a single center experience

BACKGROUND

Drug hypersensitivity reactions of immediate type pose a challenging problem, especially, if standard diagnostic procedures do not lead to conclusive results. The aim of this investigation is to identify, whether basophil activation test (BAT) is able to provide additional benefit in the diagnostic evaluation of immediate type drug hypersensitivity reactions to antibiotics in comparison with the routine allergological diagnostic methods.

MATERIALS AND METHODS

We investigated patients, who presented to the Department of Dermatology and Allergology of the University Hospital of RWTH Aachen in Germany for diagnostic workup of type I allergic reactions to antibiotics during the period from 2009 to 2012. The analysis was performed retrospectively based on patient records. The inclusion criteria were performed standard allergological in vivo diagnostic and a BAT as a part of diagnostic workup.

RESULTS

Eighty-two diagnostic investigations were performed in 52 patients. BAT was positive in 9 of 12 cases with a positive clinical history but negative skin test results. Furthermore, all patients who reported severe drug hypersensitivity reactions (anaphylactic reaction grade 2 and above) showed positive BAT (5/5), while only three of these five cases demonstrated a positive skin testing that led to the conclusion of possible immediate type drug hypersensitivity.

CONCLUSIONS

Although skin tests remain the most important part of the primary diagnostic investigation, BAT is an additional valuable and sensitive in vitro test in the diagnostic procedure of immediate type allergic reactions to antibiotics. However, further standardized investigations are needed in order to calculate exact sensitivity and specificity of this diagnostic tool in both, adult and pediatric populations.

Molecular effects of fractional ablative erbium:YAG laser treatment with multiple stacked pulses on standardized human three-dimensional organotypic skin models

The molecular changes in gene expression following ablative laser treatment of skin lesions, such as atrophic scars and UV-damaged skin, are not completely understood. A standardized in vitro model of human skin, to study the effects of laser treatment on human skin, has been recently developed. Therefore, the aim of the investigation was to examine morphological and molecular changes caused by fractional ablative erbium:YAG laser treatment on an in vitro full-thickness 3D standardized organotypic model of human skin. A fractional ablative erbium:YAG laser was used to irradiate organotypic human 3D models. Laser treatments were performed at four different settings using a variety of stacked pulses with similar cumulative total energy fluence (60 J/cm²). Specimens were harvested at specified time points and real-time PCR (qRT-PCR) and microarray studies were performed. Frozen sections were examined histologically. Three days after erbium:YAG laser treatment, a significantly increased mRNA expression of matrix metalloproteinases and their inhibitors (MMP1, MMP2, MMP3, TIMP1, and TIMP2), chemokines (CXCL1, CXCL2, CXCL5, and CXCL6), and cytokines such as IL6, IL8, and IL24 could be detected. qRT-PCR studies confirmed the enhanced mRNA expression of IL6, IL8, IL24, CXCLs, and MMPs. In contrast, the mRNA expression of epidermal differentiation markers, such as keratin-associated protein 4, filaggrin, filaggrin 2, and loricrin, and antimicrobial peptides (S100A7A, S100A9, and S100A12) as well as CASP14, DSG2, IL18, and IL36β was reduced. Four different settings with similar cumulative doses have been tested (N10%, C10%, E10%, and W25%). These laser treatments resulted in different morphological changes and effects on gene regulations. Longer pulse durations (1000 μs) especially had the strongest impact on gene expression and resulted in an upregulation of genes, such as collagen-1A2, collagen-5A2, and collagen-6A2, as well as FGF2. Histologically, all treatment settings resulted in a complete regeneration of the epidermis 3 days after irradiation. Fractional ablative erbium:YAG laser treatment with a pulse stacking technique resulted in histological alterations and shifts in the expression of various genes related to epidermal differentiation, inflammation, and dermal remodeling depending on the treatment setting applied. A standardized in vitro 3D model of human skin proved to be a useful tool for exploring the effects of various laser settings both on skin morphology and gene expression during wound healing. It provides novel data on the gene expression and microscopic architecture of the exposed skin. This may enhance our understanding of laser treatment at a molecular level.

[Double sensitization to PR10 and PR-14 proteins]

A patient with mild oral allergy syndrome presented with a history of anaphylaxis induced by both hazelnuts and peaches. The ensuing work-up showed a double sensitization to proteins in both pathogenesis-related group 10 (e.g. Bet v1, Cor a1, Pru p1) and 14 (e.g. Pru p3, Cor a8). Such double sensitization profiles are increasingly being recognized in Europe.

The effects of constant flow bioreactor cultivation and keratinocyte seeding densities on prevascularized organotypic skin grafts based on a fibrin scaffold

Organotypic full-thickness skin grafts (OTSG) are already an important technology for treating various skin conditions and are well established for skin research and development. These obvious benefits are often impaired by the need of laborious production, their noncomplete autologous composition, and, most importantly, their lack of included vasculature. Therefore, our study focused on combining a prevascularized dermal layer with an epidermis to cultivate full-thickness skin grafts incorporating capillary-like networks. It has been shown that prevascularization accelerates ingrowth of tissue-engineered grafts, and it is a prerequisite to circumvent diffusion limits due to graft thickness. To obtain such a graft, we chose a dermal layer incorporating human umbilical vein endothelial cells (HuVEC) amid human dermal fibroblasts within a fibrin-based scaffold, seeded apically with human foreskin keratinocytes (hfKC). Our research investigated the used concept's feasibility, as well as the effect of hfKC addition on the development of a well-connected capillary-like network after approximately 21 days. In addition, we evaluated the utilization of a custom-made constant flow bioreactor for simplified cultivation of these grafts, therefore possibly easing graft production and presumably increasing their cost effectiveness. Skin grafts were assessed by conventional two-dimensional histology. In addition, software-assisted three-dimensional evaluation of the capillary-like structure networks was performed by two-photon laser scanning microscopy (TPLSM) and subsequent image processing was done with ImagePro(®) Analyzer 7.0 software, thereby evaluating its platform technology power in the field of prevascularized skin grafts. All samples showed a capillary-like structure network, but we could report a significant reduction of its total length after 14 days of tri-culture with 5×10(5)/cm(2) seeded hfKC, possibly indicating nutritional deficiencies for this particular high cell density experimental setup. Lower concentrations of hfKC did not affect the formation of the capillary-like structures significantly. The developed bioreactor simplified cultivation of prevascularized OTSG. However, a flow-dependent reduction of capillary-like structures in 1 and 5 mL/min flow conditions occurred. We conclude that our technique for creating prevascularized OTSG is feasible. In addition, TPLSM is well suited for analyzing the prevascularization process. We hypothesize that the handling benefits of our bioreactor can be preserved by using considerably lower flow rates while not impairing the forming of capillary-like structure networks.

[Anaphylaxis to PR-10 proteins (Bet v1 homologues)]

Secondary food allergies to PR-10 proteins (Bet v1 homologues) are the most common food allergies in Germany. Clinically they present with an oral allergy syndrome (intraoral pruritus and perhaps swelling). When drinks containing PR-10 proteins are rapidly consumed, for example after sporting activities, large concentrations of allergen can be reached without any intraoral symptoms and then lead to anaphylaxis. This phenomenon has often been described for soja milk and occurred in our case with an apple drink with 60% fruit concentration. It seems likely that such cases of anaphylaxis are not adequately represented in the anaphylaxis registry.

Surveillance program for former PCB-exposed workers of a transformer and capacitor recycling company, family members, employees of surrounding companies, and area residents--executive summary

In a German company polychlorinated biphenyls (PCB)-containing transformers and capacitors were recycled on a large scale. Human biomonitoring revealed a high PCB body burden in workers of the recycling company, in surrounding locations of this plant, in companies in the neighborhood of this plant, and in family members of these employees. In order to clarify whether possible adverse health effects occurred or may occur in the future, a prospective surveillance program was initiated. After an extensive literature search, an interdisciplinary group of experts developed a surveillance program based on current knowledge with respect to possible adverse health effects that might occur in the recycling process of transformers and capacitors. Exposure to various hazardous substances (PCB, polychlorinated dibenzo-p-dioxins and dibenzo-furans [PCDD/F], metals, solvents) was considered. Criteria derived from human biomonitoring results of PCB were used for admission to the program. Participants in the surveillance program are first informed about risks and aims of the program. Subsequently, physicians started a detailed documentation of participants' general and occupational history, with their complaints, diseases, and nutritional habits, as well as information regarding their living areas, by means of a standardized questionnaire. In addition, separate examinations were performed to detect possible neurological, immunological, (neuro)psychological, hormonal, and skin effects. Moreover, DNA exposure as assessed by the comet assay and antioxidative status were determined. The program will be offered at yearly intervals for 3 years, and then at 5 and 10 years after program onset. Until now the program has proved to be feasible, and acceptance among workers and their families has been high. Based on the results, criteria will be developed to define adverse health effects that might be attributable to a hazardous substance exposure.

High-resolution transcriptional profiling of chemical-stimulated dendritic cells identifies immunogenic contact allergens, but not prohaptens

Allergic contact dermatitis is a complex syndrome and knowledge about the in vitro detection of small-molecular-weight compounds, particularly prohaptens, is limited. Therefore, we investigated chemical-induced gene expression changes in human antigen-presenting cells upon stimulation with immunogenic contact allergens, prohaptens and irritants. Monocyte-derived dendritic cells (moDCs) and THP-1 cells were stimulated with the prohapten cinnamic alcohol (CAlc), the hapten cinnamic aldehyde (CAld), an irritant and an obligatory sensitizer in vitro. Whole-genome screening and consecutive PCR analysis of differential gene expression in moDCs stimulated with either CAld or the obligatory sensitizer revealed coregulation of 11 marker genes which were related to immunological reactions (IL-8, CD1e, CD200R1, PLA2G5, TNFRSF11A), oxidative or metabolic stress responses (AKR1C3, SLC7A11, GCLM) or other processes (DPYLS3, TFPI, TRIM16). In contrast, the prohapten CAlc and the irritant did not change marker gene expression. In THP-1 cells, CAld and the positive control elicited similar expression changes in only 4 of the previously identified genes (IL-8, TRIM16, CD200R1, GCLM). In conclusion, we provide important insights into the pathophysiological basis of allergic contact dermatitis, identify marker genes suitable for skin hazard assessment and demonstrate that contact-allergenic prohaptens escape in in vitro detection if their skin metabolism is not taken into account.

Expression and induction of cytochrome p450 isoenzymes in human skin equivalents

Organotypic skin models are frequently used for a wide range of applications and latterly also for dermatotoxicological studies. To evaluate their practicability for the investigation of xenobiotic metabolism in human skin we compared three types of organotypic skin models, acquired by purchase from different manufacturers, to a self-constructed in-house model with regard to cytochrome P450 (CYP) isoenzyme expression on mRNA and protein level and the inducibility of these enzymes by aryl hydrocarbon receptor ligands. To induce enzyme activity, models were treated with benzanthracene, liquor carbonis detergens, pix lithanthracis or dimethyl sulfoxide as a solvent control. RNA was isolated by phenol-chloroform extraction and purified. Gene expression patterns were studied by cDNA microarray analysis. Microarray data were confirmed by real-time PCR. For quality control of the models and to detect and localize enzyme expression, immunofluorescence staining was performed with antibodies against CYPs and structure proteins. The immunofluorescence staining demonstrated the regular structure of our models. We could provide evidence for the expression of CYP types 1A1, 1B1, 2E1, 2C and 3A5 in organotypic skin models. The expression of CYP1A1 and CYP1B1 was highly inducible by treatment with liquor carbonis detergens. The proof of the expression and inducibility of CYP enzymes in organotypic skin models suggests that skin equivalents are a valuable tool that can emulate CYP-dependent metabolism of drugs and other xenobiotics in human skin.

In vitro detection and characterization of drug hypersensitivity using flow cytometry

BACKGROUND

The lymphocyte transformation test (LTT) is the only in vitro test for detecting drug sensitization at the cellular level irrespective of the reaction's phenotype. However, the LTT includes working with radioactive substances and is considered impracticable for routine laboratory investigation.

OBJECTIVE

The aim of this study was to assess drug-specific cytokine production by means of flow cytometry as an alternative nonradioactive approach which may be more appropriate for routine testing and may provide in addition more information about the pathophysiology of the reaction than proliferation-based assays, like the LTT.

METHOD

Peripheral blood mononuclear cells of 19 patients were incubated with culprit drugs (n = 28) or irrelevant antigens (n = 10). Ten healthy persons served as controls for all different drugs (n = 15). Intracellular interleukin (IL)-5, interferon (IFN)-gamma and IL-10 production was investigated using flow cytometry. Accuracy of the flow cytometry test system was confirmed using different statistical tests, i.e. receiver operating characteristic curve and Mann-Whitney rank test. In addition, drug-specific secretion of IL-5, IL-2 and IFN-gamma were analysed using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Drug-specific cytokine production could be demonstrated in 75% of the patients using flow cytometry and in 79% using ELISA respectively. Combining ELISA and flow cytometry increased the sensitivity to 100%. Analysis of involved T-cell subsets [e.g. CD4(+) or CD8(+); T helper (TH) 1 or TH 2] allowed characterization of the in vitro lymphocyte reactivity pattern.

CONCLUSIONS

Analysis of drug-specific cytokine production by means of flow cytometry proved a useful and reliable approach for the in vitro detection and characterization of drug hypersensitivities.

Microarrays of recombinant Hevea brasiliensis proteins: a novel tool for the component-resolved diagnosis of natural rubber latex allergy

BACKGROUND

Component-resolved diagnosis using microarray technology has recently been introduced in clinical allergology, but its applicability in patients with natural rubber latex (NRL) allergy has not been investigated.

OBJECTIVES

To evaluate the utility of microarray-based immunoglobulin (Ig) E detection in the diagnostic workup of NRL allergy and to compare this new diagnostic tool with established methods of NRL-specific IgE detection.

METHODS

We investigated 52 adults with immediate-type NRL allergy and 50 control patients. Determination of specific serum IgE against 8 recombinant Hevea brasiliensis allergen components was performed using a customized allergen microarray and a conventional fluorescence enzyme immunoassay (FEIA).

RESULTS

The panel of microarrayed allergen components was shown to represent a comprehensive repertoire of clinically relevant NRL proteins. NRL-specific IgE recognition patterns and sensitization rates determined by microarray analysis were similar to those obtained by conventional FEIA. The diagnostic sensitivity rates of combined single-component data were not significantly different for the respective recombinant test system, whereas the sensitivity level of extract-based FEIA analysis was markedly higher.

CONCLUSION

The current study provides evidence that microarrays of recombinant NRL allergen components are a suitable new tool for the diagnosis of NRL-specific sensitization.They show performance characteristics comparable to those of current diagnostic tests and could be indicated in small children in whom only limited blood volumes are obtainable. Further large-scale studies in unselected patient populations and in high-risk groups are warranted before the microarray can be introduced into routine management of patients with NRL allergy.

Research in practice: the second barrier of the human skin

A major function of human skin is to form an effective barrier between the environment and the inside of the organism. Especially important for this function is the activity of the physical barrier of the skin, which is mainly located in the stratum corneum. To improve this barrier function of the skin, skin protection agents are used. Recent studies have revealed that application of skin protection agents before exposition to xenobiotics does not generally reduce the percutaneous uptake of these compounds. These findings indicate that besides new study designs and improved test systems, there seems to be a need for new therapeutic approaches for more effective skin protection. In this light, new findings regarding a second barrier function of the human skin, the biochemical/toxicological barrier, could be of interest. A crucial part of this barrier function are members of the cytochrome P450 (CYP) family and efflux-transport proteins of the multidrug resistance-related protein family (MRPs), which are mainly expressed by basal layer keratinocytes. Recent studies have revealed that besides the physiological and protective function of these transport proteins and CYP enzymes in skin cells, the same proteins also play a role in the transport of contact allergens and activation of prohaptens to haptens causing contact dermatitis. Inhibition of this metabolism mediated activation of prohaptens and stimulation of the active elimination of contact allergens from skin cells could represent novel mechanisms improving the established tools for skin protection.

Soluble immune receptor serum levels are associated with age, but not with clinical phenotype or disease severity in childhood atopic dermatitis

BACKGROUND

Soluble immune receptors (SIRs) have been proposed as biomarkers in patients with atopic dermatitis (AD). However, their clinical applicability in affected children has rarely been studied.

OBJECTIVE

To assess the diagnostic usefulness of serum SIRs in childhood AD by correlating the obtained receptor profiles with serological parameters and clinical features such as age, AD phenotype and disease severity.

METHODS

We investigated 100 children with AD. The sCD14, sCD23, sCD25, sCD30, total IgE (tIgE) and eosinophilic cationic protein (ECP) were determined using sera of all children. The clinical phenotype was classified as extrinsic AD (ADe) or intrinsic AD (ADi) by the presence of allergen-specific IgE antibodies.

RESULTS

A total of 55 male and 45 female children were recruited. The sCD23, sCD25 and sCD30 serum levels revealed significant age-dependency. At a mean SCORAD of 40 (range 8-98), none of the evaluated SIRs was correlated to disease severity. In all, 73% of patients suffered from ADe while 27% showed the ADi phenotype. None of the analysed SIRs differed significantly between ADe and ADi patients, while tIgE and ECP levels were elevated in the ADe subgroup.

CONCLUSION

The current study provides evidence that sCD23, sCD25 and sCD30 serum levels are highly age-dependent. Serum concentrations of all investigated SIRs did not significantly correlate with disease severity in children with AD and were not differentially expressed in patients of different AD phenotypes. Therefore, we believe that the studied SIRs cannot be regarded as clinically useful biomarkers for the assessment of childhood AD.

Total serum IgE as a parameter to differentiate between intrinsic and extrinsic atopic dermatitis in children

Atopic dermatitis (AD) has been sub-classified into extrinsic and intrinsic types according to the presence or not of allergen-specific IgE antibodies. Although total serum IgE levels are frequently elevated in AD, their potential to predict allergen-specific IgE (asIgE) has rare ly been studied. We investigated 103 children with AD and suspected allergen-specific sensitization. A thorough clinical examination, a structured medical history and total serum IgE and asIgE measurements were performed. Fifty-three male and 50 female patients, median age 35 months (range 3 months to 17 years), were recruited. Sixty-three percent of patients were asIgE positive, while 37% did not reveal such IgE antibodies; median total serum IgE levels were 224.0 kU/l (14-12,013 kU/l) and 25.2 kU/l (0-4352 kU/l), respectively. Associations of asIgE status with atopic co-morbidity and total serum IgE levels were statistically significant. At a cut-off total serum IgE level of 106 kU/l (sensitivity 68.7%; specificity 92.3%), positive and negative predicted values (93.6% and 64.3%, respectively) were determined. Clinical decision points predictive of positive asIgE results were identified in 90%, 95% and 99% of patients, respectively. Total serum IgE values were significantly associated with the asIgE status of investigated patients. However, these preliminary data warrant further large-scale investigations before total serum IgE levels can be regarded as a clinically useful parameter between patients with extrinsic atopic dermatitis and intrinsic atopic dermatitis.

Successful topical treatment of sorafenib-induced hand-foot skin reaction in a child with hepatocellular carcinoma

Orally active kinase inhibitors such as Sorafenib are known to elicit cutaneous side effects in the majority of adult patients, whereas specific cutaneous complications of this agent have not been described in children so far. We here present the first pediatric case of Sorafenib-induced hand-foot-skin reaction and its successful topical therapy facilitating continuation of kinase inhibitor treatment.

Saving the red baby: successful allogeneic cord blood transplantation in Omenn syndrome

Haematopoietic stem cell transplantation is the treatment of choice for severe primary immunodeficiencies, but only has moderate prognosis in Omenn syndrome as it is complicated by highly activated Omenn T-cells resulting in delayed T-cell engraftment and a high rate of graft failure. A 6 1/2 months old patient with a previously unknown compound heterozygous defect within the RAG1 gene (R474C; R975W) underwent 8/10 HLA-matched cord blood transplantation after myeloablative conditioning. Immune reconstitution was impressive with T-, B- and NK-cells reaching the median of age-dependent reference values within twelve, four and two months respectively. With a continuous decrease of activated Omenn T-cells there was a steady increase of naive, probably thymus-derived T-cells. Polyclonal B-cell activation and hypergammaglobulinaemia disappeared with B-cell engraftment. This case emphasizes that, despite their naive status and HLA-barriers, cord blood T-cells were apparently able to achieve T-effector function resulting in the elimination of all activated Omenn T-cells.