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.

Upregulation of CCL7, CCL20, CXCL2, IL-1ß, IL-6 and MMP-9 in Skin Samples of PCB Exposed Individuals-A Preliminary Study.

Polychlorinated biphenyls (PCBs) are well known immunotoxic and carcinogenic compounds. Although cutaneous symptoms are the hallmark of exposure to these compounds, exact pathophysiologic mechanisms are not well understood. We took skin biopsies from moderately high PCB exposed workers (n = 25) after an informed consent and investigated the expression of immunological markers such as CCL-7, CCL-20, CXCL2, IL-1ß and IL-6, as well as the matrix metalloproteinase MMP-9, EPGN and NRF2 by RT-qPCR, and compared expression levels with plasma PCB levels. Statistical analyses showed a significant correlation between CCL-20, CXCL2, IL-6, IL-1ß, CCL-7 and MMP-9 and PCB serum levels. EPGN and NRF2 were not correlated to PCB levels in the blood. We found a significant correlation of genes involved in autoimmune, auto-inflammatory and carcinogenesis in skin samples of PCB exposed individuals with elevated plasma PCB levels. Confirmation of these findings needs to be performed in bigger study groups and larger gen-sets, including multiple housekeeping genes. Further study needs to be performed to see whether a chronical exposure to these and similar compounds can cause higher incidence of malignancies and inflammatory disease.

Establishment of an Intradermal Ear Injection Model of IL-17A and IL-36γ as a Tool to Investigate the Psoriatic Cytokine Network.

Psoriasis is a chronic skin disease affecting 2-3% of the global population. The proinflammatory IL-17A is a key cytokine in psoriasis. Accumulating evidence has revealed that IL-36γ plays also a pathogenic role. To understand more precisely the role of the IL-17A-IL-36γ cytokine network in skin pathology, we used an ear injection model. We injected IL-17A or IL-36γ alone and in combination into the ear pinnae of mice. This resulted in a significant increase in ear thickness measured over time. Histological evaluation of IL-17A + IL-36γ-treated skin showed a strong acanthosis, hyperparakeratosis and infiltration of neutrophils. The same histological features were found in mice after injection of IL-36γ alone, but to a lesser extent. IL-17A alone was not able to induce psoriasis-like changes. Genes encoding proteins of the S100 family, antimicrobial peptides and chemo-attractants for neutrophils were upregulated in the IL-17A + IL-36γ group. A much weaker expression was seen after the injection of each cytokine alone. These results strengthen the hypothesis that IL-17A and IL-36γ drive psoriatic inflammation via a synergistic interaction. Our established intradermal ear injection model can be utilized in the future to monitor effects of various inhibitors of this cytokine network.

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.

"New" inhalant plant allergens.

Specific IgE measurements obtained from patients suffering from respiratory allergy (n = 952) show that, despite similar climatic conditions, there are clear regional differences in pollen sensitization between North Rhine-Westphalia and Bavaria. The data on sensitization levels and pollen concentration was taken from the research and development project Ufoplan 3710 61 228 of the German Environment Agency for North Rhine-Westphalia and Bavaria (2011 - 2014). Most poly-sensitized patients have already shown sensitization, both in the form of cross-reactivity and species-specific sensitization, to "new" pollen allergens, such as Bermuda grass and olive tree. These plants are currently not common in Germany, but may become considerably more widespread due to the increase in average yearly temperatures caused by the global warming. The other "new" aeroallergens discussed here are plants that can be found throughout Germany, such as nettle, cypress, and pine. Their current sensitization levels are higher than 8%; however, their clinical impact appears to be underestimated. For clinical practice it is important to identify when patients' symptoms are typically severe and which regional plants might be responsible for the patients' complaints in this period of time, as this affects further diagnostic strategy. Allergens having an immune effect can then be targeted by specific immunotherapies. The information on complaints of the patients should be regularly recorded in symptom diaries. Recording this information for at least 1 year may allow to discover a correlation between specific types of pollen and allergy symptoms.

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.

Altered Gene Expression in Dioxin-Like and Non-Dioxin-Like PCB Exposed Peripheral Blood Mononuclear Cells.

Polychlorinated biphenyls (PCBs) are well known carcinogenic persistent environmental pollutants and endocrine disruptors. Our aim was to identify the possible dysregulation of genes in PCB exposed peripheral blood mononuclear cells (PBMCs) in order to give more insight into the differential pathophysiological effects of PCB congeners and mixtures, with an emphasis on immunological effects and oxidative stress. The PBMCs of a healthy volunteer (male, 56 years old) were exposed to a mixture of dioxin-like (DL)-PCBs (PCB 77, 81, 105, 114, 118, 123, 126, 156, 157, 167, 169, and 189, 250 µg/L resp.) or non-dioxin-like (NDL)-PCBs (PCB 28, 52, 101, 138, 153, 180, 250 µg/L resp.) or single PCB congener (no.28, 138, 153, 180, 250 µg/L resp.). After an incubation period of 24 h, a microarray gene expression screening was performed, and the results were compared to gene expression in control samples (PBMCs treated with the vehicle iso-octane). Treatment of PBMCs with the DL-PCB mixture resulted in the largest number of differentially regulated genes (181 upregulated genes >2-fold, 173 downregulated >2-fold). Treatment with the NDL-PCB mix resulted in 32 upregulated genes >2-fold and 12 downregulated genes >2-fold. A gene set enrichment analysis (GSEA) on DL-PCB treated PBMCs resulted in an upregulation of 125 gene sets and a downregulation of 76 gene sets. Predominantly downregulated gene sets were involved in immunological pathways (such as response to virus, innate immune response, defense response). An upregulation of pathways related to oxidative stress could be observed for all PCB congeners except PCB-28; the latter congener dysregulated the least number of genes. Our experiment augments the information known about immunological and cellular stress responses following DL- as well as NDL-PCB exposure and provides new information on PCB 28. Further studies should be performed to evaluate how disruption of these pathways contributes to the development of autoimmune diseases and cancer.

Expression of CYP1A1, CYP1B1 and IL-1ß in PBMCs and skin samples of PCB exposed individuals.

Polychlorinated biphenyls (PCBs) are well- known man-made persistent environmental pollutants and endocrine disruptors. As a result of mass production in the past, background levels of these compounds can be measured in human blood worldwide. In 2010 high internal levels of PCBs were discovered in workers of a transformer-recycling company in Germany. Our aim was to measure, whether the expression of CYP1A1, CYP1B1, and IL-1ß is dysregulated in peripheral blood mononuclear cells (PBMCs) of the exposed individuals (n = max 308). Further, we measured the regulation of CYP1A1, CYP1B1, AHRR (aromatic hydrocarbon receptor repressor) and IL-1ß in skin samples of 25 workers with elevated plasma PCB levels using quantitative PCR (q-RT-PCR). We found a significant correlation between the regulation of IL-1ß in skin samples and lipid adjusted PCB levels. In the PBMCs, the expression levels of CYP1A1, CYP1B1 and IL-1ß decreased over time with decreasing PCB plasma levels. The upregulation of the cytokine IL-1ß in exposed individuals with higher PCB plasma levels warrants further investigation in order to examine its role in the pathophysiology of autoimmune disorders and tumor promotion.

The psoriasis-associated IL-17A induces and cooperates with IL-36 cytokines to control keratinocyte differentiation and function.

Psoriasis is a TH17-driven inflammatory disease affecting a significant proportion of the world population. The molecular consequences of IL-17 signaling in the skin are only partially understood. Therefore, we evaluated the IL-17A effects on organotypic 3-dimensional skin models and observed that IL-17A interfered with keratinocyte differentiation. In agreement with this phenotype, IL-17A repressed the expression of many genes encoding structural proteins. Moreover, genes encoding anti-microbial peptides were induced, resulting in a strengthening of the chemical barrier. Finally, we observed enhanced expression of the three IL-36 cytokines IL-36α, ß and γ. We found that IL-36γ was secreted from keratinocytes in an inactive form and that neutrophilic proteases, including elastase, were capable of activating this cytokine. Functionally and similar to IL-17A, truncated IL-36 cytokines interfered with keratinocyte differentiation in 3D models. The molecular analysis revealed strong cooperative effects of IL-17A and IL-36 cytokines in regulating target genes, which was dependent on the proteolytic activation of the latter. Together these findings suggest an amplification cycle that can be initiated by IL-17A, involving IL-36 cytokines and immune cell derived proteases and resulting in active IL-36 cytokines which synergize with IL-17A. This amplification cycle might be relevant for a persistent psoriatic phenotype.

Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin.

The response of the skin to harmful environmental agents is shaped decisively by the status of the immune system. Keratinocytes constitutively express and secrete the chemokine-like mediator, macrophage migration inhibitory factor (MIF), more strongly than dermal fibroblasts, thereby creating a MIF gradient in skin. By using global and epidermis-restricted Mif-knockout (Mif-/- and K14-Cre+/tg; Miffl/fl) mice, we found that MIF both recruits and maintains antigen-presenting cells in the dermis/epidermis. The reduced presence of antigen-presenting cells in the absence of MIF was associated with accelerated and increased formation of nonmelanoma skin tumors during chemical carcinogenesis. Our results demonstrate that MIF is essential for maintaining innate immunity in skin. Loss of keratinocyte-derived MIF leads to a loss of control of epithelial skin tumor formation in chemical skin carcinogenesis, which highlights an unexpected tumor-suppressive activity of MIF in murine skin.-Brocks, T., Fedorchenko, O., Schliermann, N., Stein, A., Moll, U. M., Seegobin, S., Dewor, M., Hallek, M., Marquardt, Y., Fietkau, K., Heise, R., Huth, S., Pfister, H., Bernhagen, J., Bucala, R., Baron, J. M., Fingerle-Rowson, G. Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin.

Synthesis of a Sulfonimidamide-Based Analog of Tasisulam and Its Biological Evaluation in the Melanoma Cell Lines SKMel23 and A375.

Tasisulam is a promising antitumor agent with complex pharmacology, which is used as an antiproliferative agent in patients with metastatic melanoma and other solid tumors. Phase 2 melanoma studies showed promising results but had to be stopped because of insufficient tasisulam clearance leading to toxic side effects. To reduce the negative effects of tasisulam, we synthesized a novel sulfonimidamide-based analog to evaluate its antiproliferative effects in comparison to the original compound by performing a cell proliferation assay in melanoma cell lines SKMel23 and A375. The results revealed that the analog had inhibitory effects on the proliferation comparable to tasisulam in both investigated cell lines. These results could contribute to a reduced toxicity of tasisulam and lead to further clinical trials in metastatic melanoma.