Allergy to PEG (polyethylene glycol) - sensitivity of basophil activation test with COVID-19 mRNA-vaccine BNT162B2.

Basophil activation test (BAT) with COVID-19 mRNA vaccine seems particularly suitable for detecting sensitization to polyethylene glycol (PEG) in patients with PEG allergy. It was the aim of this study to determine the cutoffs for BAT using BNT162B2 (Comirnaty®) in a larger group of PEG allergic patients and controls. 10 PEG allergic patients and 10 controls were studied. BAT was performed using anti-CCR3 for basophil identification and anti-CD63 to assess basophil activation. Incubations with BNT162B2 at four different concentrations were performed. Basophil activation was significantly higher in PEG allergic patients compared to controls at the higher concentrations used. ROC curves showed best results with a sensitivity of 60% and specificity of 100% with a cutoff of 5% CD63+ basophils at a concentration of 4.5 µg/ml. Controls showed no positive results. In our group of PEG allergic patients, a concentration of 4.5 µg/ml BNT162B2 with a cutoff of 5% CD63+ basophils was the most suitable condition for identifying patients with a sensitization to PEG. Allergological work-up of PEG allergic patients including BAT with PEGylated lipid nanoparticles might play a role in the future when these substances will be used for other vaccines and cancer immunotherapies.

Machine Learning Analysis of Human Skin by Optoacoustic Mesoscopy for Automated Extraction of Psoriasis and Aging Biomarkers.

Ultra-wideband raster-scan optoacoustic mesoscopy (RSOM) is a novel modality that has demonstrated unprecedented ability to visualize epidermal and dermal structures in-vivo. However, an automatic and quantitative analysis of three-dimensional RSOM datasets remains unexplored. In this work we present our framework: Deep Learning RSOM Analysis Pipeline (DeepRAP), to analyze and quantify morphological skin features recorded by RSOM and extract imaging biomarkers for disease characterization. DeepRAP uses a multi-network segmentation strategy based on convolutional neural networks with transfer learning. This strategy enabled the automatic recognition of skin layers and subsequent segmentation of dermal microvasculature with an accuracy equivalent to human assessment. DeepRAP was validated against manual segmentation on 25 psoriasis patients under treatment and our biomarker extraction was shown to characterize disease severity and progression well with a strong correlation to physician evaluation and histology. In a unique validation experiment, we applied DeepRAP in a time series sequence of occlusion-induced hyperemia from 10 healthy volunteers. We observe how the biomarkers decrease and recover during the occlusion and release process, demonstrating accurate performance and reproducibility of DeepRAP. Furthermore, we analyzed a cohort of 75 volunteers and defined a relationship between aging and microvascular features in-vivo. More precisely, this study revealed that fine microvascular features in the dermal layer have the strongest correlation to age. The ability of our newly developed framework to enable the rapid study of human skin morphology and microvasculature in-vivo promises to replace biopsy studies, increasing the translational potential of RSOM.

Diagnosis and treatment of Hymenoptera venom allergy: S2k Guideline of the German Society of Allergology and Clinical Immunology (DGAKI) in collaboration with the Arbeitsgemeinschaft für Berufs- und Umweltdermatologie e.V. (ABD), the Medical Association of German Allergologists (AeDA), the German Society of Dermatology (DDG), the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery (DGHNOKC), the German Society of Pediatrics and Adolescent Medicine (DGKJ), the Society for Pediatric Allergy and Environmental Medicine (GPA), German Respiratory Society (DGP), and the Austrian Society for Allergy and Immunology (ÖGAI).

Hymenoptera venom (HV) is injected into the skin during a sting by Hymenoptera such as bees or wasps. Some components of HV are potential allergens and can cause large local and/or systemic allergic reactions (SAR) in sensitized individuals. During their lifetime, ~ 3% of the general population will develop SAR following a Hymenoptera sting. This guideline presents the diagnostic and therapeutic approach to SAR following Hymenoptera stings. Symptomatic therapy is usually required after a severe local reaction, but specific diagnosis or allergen immunotherapy (AIT) with HV (VIT) is not necessary. When taking a patient's medical history after SAR, clinicians should discuss possible risk factors for more frequent stings and more severe anaphylactic reactions. The most important risk factors for more severe SAR are mast cell disease and, especially in children, uncontrolled asthma. Therefore, if the SAR extends beyond the skin (according to the Ring and Messmer classification: grade > I), the baseline serum tryptase concentration shall be measured and the skin shall be examined for possible mastocytosis. The medical history should also include questions specific to asthma symptoms. To demonstrate sensitization to HV, allergists shall determine concentrations of specific IgE antibodies (sIgE) to bee and/or vespid venoms, their constituents and other venoms as appropriate. If the results are negative less than 2 weeks after the sting, the tests shall be repeated (at least 4 - 6 weeks after the sting). If only sIgE to the total venom extracts have been determined, if there is double sensitization, or if the results are implausible, allergists shall determine sIgE to the different venom components. Skin testing may be omitted if in-vitro methods have provided a definitive diagnosis. If neither laboratory diagnosis nor skin testing has led to conclusive results, additional cellular testing can be performed. Therapy for HV allergy includes prophylaxis of reexposure, patient self treatment measures (including use of rescue medication) in the event of re-stings, and VIT. Following a grade I SAR and in the absence of other risk factors for repeated sting exposure or more severe anaphylaxis, it is not necessary to prescribe an adrenaline auto-injector (AAI) or to administer VIT. Under certain conditions, VIT can be administered even in the presence of previous grade I anaphylaxis, e.g., if there are additional risk factors or if quality of life would be reduced without VIT. Physicians should be aware of the contraindications to VIT, although they can be overridden in justified individual cases after weighing benefits and risks. The use of ß-blockers and ACE inhibitors is not a contraindication to VIT. Patients should be informed about possible interactions. For VIT, the venom extract shall be used that, according to the patient's history and the results of the allergy diagnostics, was the trigger of the disease. If, in the case of double sensitization and an unclear history regarding the trigger, it is not possible to determine the culprit venom even with additional diagnostic procedures, VIT shall be performed with both venom extracts. The standard maintenance dose of VIT is 100 µg HV. In adult patients with bee venom allergy and an increased risk of sting exposure or particularly severe anaphylaxis, a maintenance dose of 200 µg can be considered from the start of VIT. Administration of a non-sedating H1-blocking antihistamine can be considered to reduce side effects. The maintenance dose should be given at 4-weekly intervals during the first year and, following the manufacturer's instructions, every 5 - 6 weeks from the second year, depending on the preparation used; if a depot preparation is used, the interval can be extended to 8 weeks from the third year onwards. If significant recurrent systemic reactions occur during VIT, clinicians shall identify and as possible eliminate co-factors that promote these reactions. If this is not possible or if there are no such co-factors, if prophylactic administration of an H1-blocking antihistamine is not effective, and if a higher dose of VIT has not led to tolerability of VIT, physicians should should consider additional treatment with an anti IgE antibody such as omalizumab as off lable use. For practical reasons, only a small number of patients are able to undergo sting challenge tests to check the success of the therapy, which requires in-hospital monitoring and emergency standby. To perform such a provocation test, patients must have tolerated VIT at the planned maintenance dose. In the event of treatment failure while on treatment with an ACE inhibitor, physicians should consider discontinuing the ACE inhibitor. In the absence of tolerance induction, physicians shall increase the maintenance dose (200 µg to a maximum of 400 µg in adults, maximum of 200 µg HV in children). If increasing the maintenance dose does not provide adequate protection and there are risk factors for a severe anaphylactic reaction, physicians should consider a co-medication based on an anti-IgE antibody (omalizumab; off-label use) during the insect flight season. In patients without specific risk factors, VIT can be discontinued after 3 - 5 years if maintenance therapy has been tolerated without recurrent anaphylactic events. Prolonged or permanent VIT can be considered in patients with mastocytosis, a history of cardiovascular or respiratory arrest due to Hymenoptera sting (severity grade IV), or other specific constellations associated with an increased individual risk of recurrent and/or severe SAR (e.g., hereditary α-tryptasemia). In cases of strongly increased, unavoidable insect exposure, adults may receive VIT until the end of intense contact. The prescription of an AAI can be omitted in patients with a history of SAR grade I and II when the maintenance dose of VIT has been reached and tolerated, provided that there are no additional risk factors. The same holds true once the VIT has been terminated after the regular treatment period. Patients with a history of SAR grade ≥ III reaction, or grade II reaction combined with additional factors that increase the risk of non response or repeated severe sting reactions, should carry an emergency kit, including an AAI, during VIT and after regular termination of the VIT.

Fast raster-scan optoacoustic mesoscopy enables assessment of human melanoma microvasculature in vivo.

Melanoma is associated with angiogenesis and vascular changes that may extend through the entire skin depth. Three-dimensional imaging of vascular characteristics in skin lesions could therefore allow diagnostic insights not available by conventional visual inspection. Raster-scan optoacoustic mesoscopy (RSOM) images microvasculature through the entire skin depth with resolutions of tens of micrometers; however, current RSOM implementations are too slow to overcome the strong breathing motions on the upper torso where melanoma lesions commonly occur. To enable high-resolution imaging of melanoma vasculature in humans, we accelerate RSOM scanning using an illumination scheme that is coaxial with a high-sensitivity ultrasound detector path, yielding 15 s single-breath-hold scans that minimize motion artifacts. We apply this Fast RSOM to image 10 melanomas and 10 benign nevi in vivo, showing marked differences between malignant and benign lesions, supporting the possibility to use biomarkers extracted from RSOM imaging of vasculature for lesion characterization to improve diagnostics.

Use of biologicals in allergic and type-2 inflammatory diseases during the current COVID-19 pandemic: Position paper of Ärzteverband Deutscher Allergologen (AeDA)A, Deutsche Gesellschaft für Allergologie und Klinische Immunologie (DGAKI)B, Gesellschaft für Pädiatrische Allergologie und Umweltmedizin (GPA)C, Österreichische Gesellschaft für Allergologie und Immunologie (ÖGAI)D, Luxemburgische Gesellschaft für Allergologie und Immunologie (LGAI)E, Österreichische Gesellschaft für Pneumologie (ÖGP)F in co-operation with the German, Austrian, and Swiss ARIA groupsG, and the European Academy of Allergy and Clinical Immunology (EAACI)H.

BACKGROUND: Since the beginning of the COVID-19 pandemic, the treatment of patients with allergic and atopy-associated diseases has faced major challenges. Recommendations for "social distancing" and the fear of patients becoming infected during a visit to a medical facility have led to a drastic decrease in personal doctor-patient contacts. This affects both acute care and treatment of the chronically ill. The immune response after SARS-CoV-2 infection is so far only insufficiently understood and could be altered in a favorable or unfavorable way by therapy with monoclonal antibodies. There is currently no evidence for an increased risk of a severe COVID-19 course in allergic patients. Many patients are under ongoing therapy with biologicals that inhibit type 2 immune responses via various mechanisms. There is uncertainty about possible immunological interactions and potential risks of these biologicals in the case of an infection with SARS-CoV-2. MATERIALS AND METHODS: A selective literature search was carried out in PubMed, Livivo, and the internet to cover the past 10 years (May 2010 - April 2020). Additionally, the current German-language publications were analyzed. Based on these data, the present position paper provides recommendations for the biological treatment of patients with allergic and atopy-associated diseases during the COVID-19 pandemic. RESULTS: In order to maintain in-office consultation services, a safe treatment environment must be created that is adapted to the pandemic situation. To date, there is a lack of reliable study data on the care for patients with complex respiratory, atopic, and allergic diseases in times of an imminent infection risk from SARS-CoV-2. Type-2-dominant immune reactions, as they are frequently seen in allergic patients, could influence various phases of COVID-19, e.g., by slowing down the immune reactions. Theoretically, this could have an unfavorable effect in the early phase of a SARS-Cov-2 infection, but also a positive effect during a cytokine storm in the later phase of severe courses. However, since there is currently no evidence for this, all data from patients treated with a biological directed against type 2 immune reactions who develop COVID-19 should be collected in registries, and their disease courses documented in order to be able to provide experience-based instructions in the future. CONCLUSION: The use of biologicals for the treatment of bronchial asthma, atopic dermatitis, chronic rhinosinusitis with nasal polyps, and spontaneous urticaria should be continued as usual in patients without suspected infection or proven SARS-CoV-2 infection. If available, it is recommended to prefer a formulation for self-application and to offer telemedical monitoring. Treatment should aim at the best possible control of difficult-to-control allergic and atopic diseases using adequate rescue and add-on therapy and should avoid the need for systemic glucocorticosteroids. If SARS-CoV-2 infection is proven or reasonably suspected, the therapy should be determined by weighing the benefits and risks individually for the patient in question, and the patient should be involved in the decision-making. It should be kept in mind that the potential effects of biologicals on the immune response in COVID-19 are currently not known. Telemedical offers are particularly desirable for the acute consultation needs of suitable patients.

The high molecular weight dipeptidyl peptidase IV Pol d 3 is a major allergen of Polistes dominula venom.

Hymenoptera venom allergy can cause severe anaphylaxis in untreated patients. Polistes dominula is an important elicitor of venom allergy in Southern Europe as well as in the United States. Due to its increased spreading to more moderate climate zones, Polistes venom allergy is likely to gain importance also in these areas. So far, only few allergens of Polistes dominula venom were identified as basis for component-resolved diagnostics. Therefore, this study aimed to broaden the available panel of important Polistes venom allergens. The 100 kDa allergen Pol d 3 was identified by mass spectrometry and found to be a dipeptidyl peptidase IV. Recombinantly produced Pol d 3 exhibited sIgE-reactivity with approximately 66% of Polistes venom-sensitized patients. Moreover, its clinical relevance was supported by the potent activation of basophils from allergic patients. Cross-reactivity with the dipeptidyl peptidases IV from honeybee and yellow jacket venom suggests the presence of exclusive as well as conserved IgE epitopes. The obtained data suggest a pivotal role of Pol d 3 as sensitizing component of Polistes venom, thus supporting its status as a major allergen of clinical relevance. Therefore, Pol d 3 might become a key element for proper diagnosis of Polistes venom allergy.

Influence of dietary factors, age and nickel contact dermatitis on nickel excretion.

BACKGROUND: Nickel is a frequently detected cause of allergic contact dermatitis. Ingestion of nickel may lead to flares of nickel contact dermatitis. METHODS: We examined nickel excretion in the urine of 164 female patients with and without nickel contact dermatitis. The associations between age, atopic dermatitis, nickel contact dermatitis and nickel exposure through nutrition (e.g. dietary supplements) and by patch tests were investigated prospectively. Nickel was measured with atomic absorption spectrometry with two different standardized methods. RESULTS: A nickel detection limit of 0.2 µg/l was exceeded by all samples. The 95th percentiles of urine nickel concentration were 3.77 µg/l (age 18-30 years) and 3.98 µg/l (age 31-46 years). Bivariate analyses pointed to significantly increased nickel excretion with increasing age, ingestion of dietary supplements, drinking of stagnant tap water, and consumption of nickel-rich food. In the multivariate analysis, age and dietary supplements remained significant predictors of high nickel excretion. A non-significant increase in the median concentration of nickel was observed after the administration of conventional nickel patch tests. Patients with atopic eczema showed urine nickel concentrations similar to those in non-atopic controls. CONCLUSIONS: The 95th percentile of nickel excretion in our study population markedly exceeded the actual reference value of 3 µg/l. Age and consumption of dietary supplements are the most important predictors. The use of stagnant tap water and consumption of nickel-rich food contribute to the total load. These factors should be explicitly mentioned when allergic patients on a low-nickel diet are counselled. In contrast, existing nickel contact sensitization was not more frequent in subjects with higher nickel excretion. Nickel patch testing may cause transient minor systemic nickel exposure. The findings of this study extend our understanding and management of factors associated with nickel allergy.

Double positivity to bee and wasp venom: improved diagnostic procedure by recombinant allergen-based IgE testing and basophil activation test including data about cross-reactive carbohydrate determinants.

BACKGROUND: Specific IgE (sIgE) antibodies to both bee and wasp venom can be due to a sensitivity to both insect venoms or due to cross-reactive carbohydrate determinants (CCDs). OBJECTIVE: Investigating whether a basophil activation test (BAT) with both venoms as well as with bromelain and horseradish peroxidase (HRP) or recombinant allergen-based IgE testing can improve the diagnostic procedure. METHODS: Twenty-two Hymenoptera-venom allergic patients with sIgE antibodies to both bee and wasp venom were studied. sIgE antibodies to MUXF3 CCD, bromelain, HRP, rApi m 1, and rVes v 5 were determined, and a BAT (Flow2 CAST) with venom extracts, bromelain, and HRP was performed. Further recombinant allergen-based IgE testing was done by using an ELISA, if required. The reactivity of basophils was calculated from the insect venom concentration at half-maximum stimulation. RESULTS: Double positivity/double negativity/single positivity to rApi m 1 and rVes v 5 was seen in 12/1/9 patients. Further recombinant allergen-based IgE testing in the last ones revealed positive results to the other venom in all cases except one. BAT was double positive/double negative/single positive in 6/2/14 patients. Four patients with negative results in sIgE antibodies to CCDs had positive results in BAT. BAT with bromelain/HRP showed a sensitivity of 50%/81% and a specificity of 91%/90%. CONCLUSION: Component-resolved IgE testing elucidates the pattern of double positivity, showing a majority of true double sensitizations independent of CCD sensitization. BAT seems to add more information about the culprit insect even if the true clinical relevance of BAT is not completely determined because of ethical limitations on diagnostic sting challenges. BAT with HRP is a good method to determine sensitivity to CCDs.

Clinical overview of cutaneous features in hypereosinophilic syndrome.

The hypereosinophilic syndromes (HES) are a heterogeneous group of disorders defined as persistent and marked blood eosinophilia of unknown origin with systemic organ involvement. HES is a potentially severe multisystem disease associated with considerable morbidity. Skin involvement and cutaneous findings frequently can be seen in those patients. Skin symptoms consist of angioedema; unusual urticarial lesions; and eczematous, therapy-resistant, pruriginous papules and nodules. They may be the only obvious clinical symptoms. Cutaneous features can give an important hint to the diagnosis of this rare and often severe illness. Based on advances in molecular and genetic diagnostic techniques and on increasing experience with characteristic clinical features and prognostic markers, therapy has changed radically. Current therapies include corticosteroids, hydroxyurea, interferon-α, the tyrosine kinase inhibitor imatinib mesylate, and (in progress) the monoclonal anti-interleukin-5 antibodies. This article provides an overview of current concepts of disease classification, different skin findings, and therapy for HES.

Lipomatous metaplasia after severe and chronic cutaneous inflammation.

A 69-year-old woman with a history of acute generalized exanthematic pustulosis (AGEP) caused by metamizole is described. Furthermore, she had suffered from an untreated psoriasis since the age of 20. After an adequate therapy of both psoriasis and AGEP, yellow-brownish, static, coalescing, lucent nodules on the thighs and upper arms became apparent. Histology of skin biopsies revealed a prominent band of mature adipocytes in the dermis. We diagnosed a lipomatous metaplasia of the dermis and hypothesize that this metaplasia occurred as a consequence of the severe and chronic inflammation of the skin.

Pollen grains induce a rapid and biphasic eczematous immune response in atopic eczema patients.

INTRODUCTION: Eczematous reactions to type I allergy-inducing antigens are documented in a subgroup of patients with atopic eczema. Yet, the underlying immunological mechanisms are not well understood. MATERIAL AND METHODS: To delineate the effect of native pollen grains on human skin of healthy and atopic individuals we performed patch tests (atopy patch test with native pollen grains, PPT). Nickel patch tests (NPT) served as an established model of contact dermatitis. Skin site biopsies were taken 6-96 h after allergen application and investigated immunohistochemically. RESULTS: Histology of positive patch tests showed an influx of mononuclear cells (predominantly CD4+, CD25+, CD45RO+). This influx was detected earlier in the PPT reaction than in the immune response to nickel. A biphasic cytokine response could be detected in the PPT: IL-5 dominated in the early, IFN-gamma in the late phase. The NPT was continuously dominated by IFN-gamma. Dendritic cell subpopulations imitated the earlier kinetics of the mononuclear infiltrate. DISCUSSION: Thus, pollen grains induce eczematous reactions in susceptible individuals. This reaction appears clinically and immunohistochemically similar to the contact hypersensitivity reaction to nickel but follows a faster kinetic and a biphasic course: Th2 and IgE in the early (24 h) and Th1 predominance in the late (96 h) phase.

Modulation of atopy patch test and skin prick test by pretreatment with 1% pimecrolimus cream.

BACKGROUND: In a subgroup of patients with atopic eczema (AE), aeroallergens are relevant eliciting factors. The atopy patch test (APT) was proposed as inflammation model for AE. OBJECTIVE: It was the aim of this study to investigate the effect of pretreatment with 1% pimecrolimus cream (Elidel) on the APT and skin prick test (SPT). METHODS: In a randomized, controlled, double-blind study, 20 patients with AE and positive SPT and APT screening reaction to house dust mite Dermatophagoides pteronyssinus, cat dander, grass or birch pollen were enrolled (age 20 +/- 11 years, 55% males). For 2 weeks, patients twice daily applied pimecrolimus and vehicle control to marked fields on their backs and forearms. Then, APT was performed (200 index of reactivity/g extracts in petrolatum; Stallergènes, France) on both fields on the back and SPT was performed on the pretreated forearms. RESULTS: Including only patients with different readings (n = 13), stronger APT suppression of at least 1 ETFAD (European Task Force on Atopic Dermatitis) grade in the pimecrolimus area versus intraindividual control was observed in 10 of these patients after 48 and 72 h (p < 0.05; 90% CI 50.5-93.4). Including all 20 subjects, the analysis still showed a borderline significance compared with the vehicle (p = 0.0564). SPT with histamine and aeroallergens showed a median 7.5-10% reduction in actively pretreated areas (p = 0.086). Immunohistochemical analysis in 2 patients revealed an induction of interferon-gamma in primecrolimus-pretreated skin. CONCLUSION: APT can be used as a model for AE skin inflammation. It was shown for the first time that pimecrolimus pretreatment has a potential to suppress the development of lesions induced by aeroallergen exposure in patients with AE.

Allergen cleavage by effector cell-derived proteases regulates allergic inflammation.

The key event of allergic inflammation, allergen-induced crosslinking of mast cell-bound IgE antibodies, is accompanied by release of inflammatory mediators, cytokines, and proteases, in particular beta-tryptase. We provide evidence that protease-mediated cleavage of allergens represents a mechanism that regulates allergen-induced mast cell activation. When used in molar ratios as they occur in vivo, purified beta-tryptase cleaved major grass and birch pollen allergens, resulting in defined peptide fragments as mapped by mass spectrometry. Tryptase-cleaved allergens showed reduced IgE reactivity and allergenic activity. The biological relevance is demonstrated by the fact that lysates from activated human mast cells containing tryptase levels as they occur in vivo cleaved allergens. Additionally, protamine, an inhibitor of heparin-dependent effector cell proteases, augmented allergen-induced release of mediators from effector cells. Protease-mediated allergen cleavage may represent an important mechanism for terminating allergen-induced effector cell activation.

Idiopathic anaphylaxis.

Anaphylaxis represents the maximal variant of an immediate-type allergic reaction involving the whole organism with manifestations in different organ systems. IgE-mediated mast cell and basophil activation is the major pathomechanism; however, immune complex and pseudo-allergic reactions also may lead to the same symptomatology. The most common elicitors are drugs, additives, occupational substances, animal venoms, aeroallergens, and contact urticariogens but also physical factors (cold, heat, ultraviolet light, exercise). When no eliciting factors can be detected, the term "idiopathic anaphylaxis" is used. The diagnosis of idiopathic anaphylaxis is, therefore, a diagnosis of exclusion and may be made only after careful allergy history taking and diagnosis involving in vitro tests. Possible mechanisms underlying the pathophysiology of idiopathic anaphylaxis include undetected diseases (eg, mastocytosis occulta), concomitant anaphylaxis-enhancing medication (b-blockers), secretion of histamine-releasing factor from T lymphocytes, autoantibodies against IgE or IgE receptors, and angiotensin II deficiency. One of the many differential diagnoses of anaphylaxis may have been overlooked. The treatment of idiopathic anaphylaxis follows the rules of antianaphylactic therapy.