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Background: In hymenoptera venom allergy, about 75% of detected in vitro double positivity to yellow jacket and honeybee venom is ascribed to specific IgE (sIgE) directed against cross-reactive carbohydrate determinants (CCDs). To date, for the detection of CCD-sIgE, different carbohydrate antigens and methods are used. The most suitable one still has to be identified. Methods: Eighty-seven patients with confirmed hymenoptera venom allergy and venom sIgE values of ≥0.7 kU/l were investigated. Sixty-five patients showed sIgE reactivity to both yellow jacket and honeybee venom, 22 were venom mono positive and served as controls. Occurrence of CCD-sIgE was determined using bromelain, horseradish peroxidase (HRP) and MUXF3 on system A, and ascorbic acid oxidase (AAO), bromelain and HRP on system B. Further, a reference standard for CCD-sIgE evaluation was created: CCD positivity was assumed when at least 4 of the 6 test results were positive. Results: According to the defined reference standard, 45/65 venom double positive patients exhibited CCD-sIgE. Using system A, comparison with the reference standard revealed sensitivity and specificity values of 96 and 97%, respectively, for MUXF3, 100 and 100%, respectively, for bromelain, and 96 and 97%, respectively, for HRP. Using system B, sensitivity and specificity was 98 and 97%, respectively, for AAO, 62 and 95%, respectively, for bromelain, and 96 and 69%, respectively, for HRP. Results of the 3 test allergens obtained with system A showed strong correlations (r = 0.932-0.976), whereas results with system B showed lower correlations (r = 0.714-0.898). Conclusions: All 3 test allergens used with system A are suitable for CCD-sIgE detection in hymenoptera venom allergy. With system B, only AAO seems to be a reliable tool. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Avoidance of allergen exposure is the basic preventive measure in reducing symptoms of immediate-type allergies. As room air cleaners were found to have no benefic effect on general health, their use has not been recommended. The purpose of this study was to evaluate the effect of a fresh air filtration system installed in the bedrooms of non-air-conditioned homes on hay fever symptoms. Methods: In a placebo-controlled, double-blind, two-period, crossover study, we investigated the effectiveness of a fresh air filtration system installed in the bedrooms of volunteers suffering from hay fever. Results: Volunteers only suffering from pollinosis reported an improvement of their allergy symptoms. We observed a significant decrease in nighttime hay fever symptoms and an increase in morning peak expiratory flow rates (PEFR). No effects were recognized in volunteers who additionally had perennial allergy. Conclusion: Based upon these results, the installation of fresh air filtration systems in bedrooms should be recommended for patients suffering from hay fever.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The concentrations of proteins, allergens and rubber chemicals are essential parameters of the allergenicity of NRL gloves. To date, a standardized method has been given only for analysis of the protein concentration (DIN EN 455-3), and not for the concentrations of allergens and rubber chemicals. In the present study, we investigated 11 brands of surgical gloves currently available on the German market. Additionally 1 glove, not subjected to final leaching procedures, was added for comparison purposes. Protein concentrations were analysed by different methods in different laboratories. Allergen concentrations were assayed by prick tests in NRL-allergic volunteers and by RAST inhibition methods. Rubber chemicals were analysed by HPTLC and GC. The protein concentrations analysed by the Lowry method in the 2 laboratories gave concordant results, but the correlations between protein and allergen concentrations were low. The protein concentration analysed by HPLC correlated with the allergen concentration, and gave better information on the allergenicity of the gloves. The development of standardized methods for allergen analysis in the assessment routine is necessary, due to significant discrepancy between protein and allergen levels of some gloves. Thiurams were not found in any of the gloves, though carbamates were present in all gloves tested. Our data indicate that washing procedures have little or no effect on the concentration of rubber chemicals. [ABSTRACT FROM AUTHOR]

Provides information on rubber latex allergy. Types of allergy caused by clinical reactions to contact with latex gloves; Identification of allergens derived from H brasiliensis in natural rubber latex; Guidelines to prevent the occurrence of allergy.

Background: Non‐sedating H1‐antihistamines (nsAH) are the most commonly used treatment for chronic spontaneous urticaria (CSU). Many patients use them as on‐demand (OD) therapy rather than a maintenance treatment. Here, we compared OD versus daily maintenance treatment with the nsAH rupatadine, assessed the efficacy of rupatadine updosing, and investigated potential long‐term disease‐modifying effects. Methods: This multicenter, randomized study consisted of 2 weeks of screening, 8 weeks of double‐blind treatment, and 6 weeks of treatment‐free follow‐up (OD allowed). Adult patients were randomized to 10 mg rupatadine OD or 10 mg rupatadine daily. At Week 4, if patients did not have a complete response, they switched from 10 to 20 mg rupatadine daily or underwent sham updosing (patients on 10 mg rupatadine OD). The primary aim was to compare CSU disease activity at the end of follow‐up between daily versus OD. Additionally, we assessed the efficacy of rupatadine updosing. Major outcomes were disease activity, CSU‐related quality of life (QoL), and disease control. Results: At Week 4, disease activity and QoL significantly improved in daily versus OD‐treated patients. Updosing of rupatadine did not improve the mean disease activity, but the number of complete responders increased during updosing from 5% to 22%. At the end of follow‐up, the disease activity of patients treated OD versus daily was not significantly different. Conclusions: Daily rupatadine treatment significantly improved CSU disease activity and QoL during treatment versus OD treatment but not after discontinuation of rupatadine, indicating the benefits of a daily maintenance nsAH schedule. [ABSTRACT FROM AUTHOR]

We present the case of a 77-year-old female patient who suffered from severe anaphylaxis during wound care. Allergologic evaluation yielded specific IgE antibodies to chlorhexidine, but anaphylaxis to chlorhexidine was not congruent with the patient history and dermal provocation tests. However, skin prick tests provided evidence for a sensitization to polyhexanide that was further supported by the detection of specific IgE antibodies to polyhexanide, the results of basophil activation tests and IgE inhibition analysis. We presume cross-reactive IgE antibodies binding to both biguanide antiseptics and identified polyhexanide as the likely cause of the anaphylactic reaction. We recognize polyhexanide as an emerging allergen that has to be considered as a cause of anaphylaxis. [ABSTRACT FROM AUTHOR]

Background: Systemic allergic reactions to vaccines are very rare. In this study we assessed the management and outcome of suspected SARS‐CoV‐2 vaccine hypersensitivity. Methods: Totally, 334 individuals underwent an allergy work up regarding SARS‐CoV‐2 vaccination (group A: 115 individuals suspected to be at increased risk for vaccine‐related reactions before vaccination and group B: 219 patients with reactions after COVID vaccination). The large majority of the SPT/IDT with the vaccines were negative; however, we identified in 14.1% (n = 47) a possible sensitization to the SARS‐CoV‐2 vaccine and/or its ingredients defined as one positive skin test. Of the 219 individuals (group B) who experienced symptoms suspicious for a hypersensitivity reaction after vaccination, 214 were reported after the first vaccination with a mRNA vaccine (157 mRNA (Comirnaty®, 38 Spikevax®) and 18 with a vector vaccine (Vaxzevria®), 5 cases were after the second vaccination. Results: The symptom profile in group B was as follows: skin symptoms occurred in 115 cases (n = 59 angioedema, n = 50 generalized urticaria and n = 23 erythema/flush. Seventy individuals had cardiovascular, 53 respiratory and 17 gastrointestinal symptoms. Of the overall 334 individuals, 78 patients tolerated (re)‐vaccination (out of skin test positive/negative 7/19 from group A and 17/35 from group B). Conclusion: Proven IgE‐mediated hypersensitivity to SARS‐CoV‐2 vaccines is extremely rare and not increased in comparison with reported hypersensitivity to other vaccines. The value of skin tests is unclear and nonspecific reactions, in particular when intradermal testing is applied, should be considered. [ABSTRACT FROM AUTHOR]

Background: Essential oils (EOs) are widely used in cosmetics, perfumes, massage fluids, aroma therapy and natural medicine. Some EOs contain contact sensitizers. Objectives: To describe the frequency of sensitization to EOs in dermatitis patients presenting in skin clinics including concomitant reactions, to evaluate the EO patch test preparations and to identify patient groups with an increased risk of EO sensitization. Patients and methods: Retrospective analysis of data from the Information Network of Departments of Dermatology (IVDK), 2010–2019. Results: Twelve EOs were patch tested in an aimed manner in 10 930 patients, of whom 908 (8.3%) reacted to at least 1 EO. Only 6 EOs elicited more than 1% positive patch test reactions: ylang ylang (I + II) oil (3.9%), lemongrass oil (2.6%), jasmine absolute (1.8%), sandalwood oil (1.8%), clove oil (1.6%) and neroli oil (1.1%). Concomitant reactions among EOs or to EOs and fragrances were frequent. Among EO‐positive patients, women, leg dermatitis patients, patients aged 40 years or more, masseurs and cosmeticians were over‐represented. Conclusions: Sensitization to EOs occurs, albeit infrequently in most cases. Masseurs and cosmeticians have an increased risk of sensitization to EOs. [ABSTRACT FROM AUTHOR]

Chronic pruritus, which is associated with a wide variety of underlying diseases, represents a challenge in diagnostics and treatment in dermatology and general medicine. The cause of pruritus remains unknown in up to 45% of patients. In this study, 718 patients with chronic pruritus were analysed concerning lactase deficiency, demographic data, aetiology, duration and intensity of pruritus. A total of 154 patients were tested positive for lactase deficiency and 38.3% showed a significant anti-pruritic response to a lactose-free diet (minimum 4 weeks). The best results were observed in patients with pruritus of mixed or unknown origin (n = 91; 64% response). Age, sex, localization or duration had no significant influence on the anti-pruritic effect of a lactose-free diet. Lactase deficiency might be an independent causal factor in the elicitation of chronic pruritus. Thus, screening for lactase deficiency represents a rational step in the diagnostic work-up of chronic pruritus. In case of a positive test result, a lactose-free diet offers a low-cost, efficient and specific therapy in patients with chronic pruritus. [ABSTRACT FROM AUTHOR]

Background: A longstanding debate in allergy is whether or not specific immunoglobulin-E antibodies (sIgE), recognizing cross-reactive carbohydrate determinants (CCD), are able to elicit clinical symptoms. In pollen and food allergy, ≳20% of patients display in-vitro CCD reactivity based on presence of α1,3-fucose and/or β1,2-xylose residues on N-glycans of plant (xylose/fucose) and insect (fucose) glycoproteins. Because the allergenicity of tomato glycoallergen Lyc e 2 was ascribed to N-glycan chains alone, this study aimed at evaluating clinical relevance of CCD-reduced foodstuff in patients with carbohydrate-specific IgE (CCD-sIgE). Methodology/Principal Findings: Tomato and/or potato plants with stable reduction of Lyc e 2 (tomato) or CCD formation in general were obtained via RNA interference, and gene-silencing was confirmed by immunoblot analyses. Two different CCD-positive patient groups were compared: one with tomato and/or potato food allergy and another with hymenopteravenom allergy (the latter to distinguish between CCD- and peptide-specific reactions in the food-allergic group). Nonallergic and CCD-negative food-allergic patients served as controls for immunoblot, basophil activation, and ImmunoCAP analyses. Basophil activation tests (BAT) revealed that Lyc e 2 is no key player among other tomato (glyco)allergens. CCDpositive patients showed decreased (re)activity with CCD-reduced foodstuff, most obvious in the hymenoptera venomallergic but less in the food-allergic group, suggesting that in-vivo reactivity is primarily based on peptide- and not CCDsIgE. Peptide epitopes remained unaffected in CCD-reduced plants, because CCD-negative patient sera showed reactivity similar to wild-type. In-house-made ImmunoCAPs, applied to investigate feasibility in routine diagnosis, confirmed BAT results at the sIgE level. Conclusions/Significance: CCD-positive hymenoptera venom-allergic patients (control group) showed basophil activation despite no allergic symptoms towards tomato and potato. Therefore, this proof-of-principle study demonstrates feasibility of CCD-reduced foodstuff to minimize 'false-positive results' in routine serum tests. Despite confirming low clinical relevance of CCD antibodies, we identified one patient with ambiguous in-vitro results, indicating need for further component-resolved diagnosis. [ABSTRACT FROM AUTHOR]

Background: IgE-mediated hypersensitivity to latex has been recognized as an increasing health problem with far-reaching consequences for patients, regarding both their occupational situation and safety in medical care. Therefore, a correct diagnosis of natural rubber latex (NRL) allergy is essential. The purpose of the study was to evaluate sensitivity and specificity of several established diagnostic methods for NRL allergy (in vitro assays and skin prick test) in relation to a new semiquantitative dipstick test (Allergodip[sup ®] -Latex, Allergopharma) as a screening test for NRL allergy. Methods: Data obtained with quantitative assays including Pharmacia CAP System[sup ®] (FEIA), DPC-AlaSTAT[sup ®] and Magic Lite[sup ®] were compared with the dipstick test results in latex-sensitized (n = 151) and nonsensitized persons (n = 232). In addition these in vitro findings were related to clinical symptoms after exposure to latex and skin prick test results with a panel of different latex allergen extracts. Results: When comparing sensitivity and specificity of all in vitro assays relative to skin prick test results the Pharmacia CAP System[sup ®] (FEIA) had the highest sensitivity in the range of 90%. Sensitivity of the other in vitro assays was in the range of 73.7–74.9%, specificity varied from 85.3 to 89.8%. A diagnostic standard was defined in terms of at least three corresponding test results out of all diagnostic methods (in vitro assays and skin prick test). The sensitivity and specificity of each diagnostic test were determined relative to this diagnostic standard. Hereby the Allergodip test results showed a sensitivity of 91% and a specificity of 93%. Conclusion: The dipstick test results are in line with the data of the other in vitro assays. In contrast to other in vitro assays the dipstick test requires no further laboratory equipment and is easy to perform.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Omalizumab, a humanized recombinant monoclonal anti‐IgE antibody, proved to be effective in patients with chronic spontaneous urticaria (CSU), including severe and treatment‐refractory CSU. Here, we report omalizumab's effect on gene expression in skin biopsies from CSU patients enrolled in a double‐blind, placebo‐controlled study. Methods: Chronic spontaneous urticaria patients (18‐75 years) were randomized to either 300 mg omalizumab (n = 20) or placebo (n = 10) administered s.c. every 4 weeks for 12 weeks (NCT01599637). Lesional and nonlesional skin biopsies were collected from the same area of consenting patients and assessed at baseline and on Day 85 compared with skin biopsies from the same area of 10 untreated healthy volunteers (HVs). Gene expression data were generated using Affymetrix HG‐U133Plus2.0 microarrays. Statistical analyses were performed using R packages. Results: At baseline, 63 transcripts were differentially expressed between lesional and nonlesional skin. Two‐thirds of these lesional signatures were also differentially expressed between lesional and HV skin. Upon treatment with omalizumab, >75% of lesional signatures changed to reflect nonlesional skin expression levels (different vs placebo, P < 0.01). Transcripts upregulated in lesional skin (vs nonlesional and/or HV skin) suggested increased mast cell/leukocyte infiltration (FCER1G, C3AR1, CD93, S100A8, and S100A9), increased oxidative stress, vascularization (CYR61), and skin repair events (KRT6A, KRT16). Lesional signatures were not modulated by treatment in nonresponders (defined based on UAS7 longitudinal changes ≥16). Conclusion: Omalizumab, in treatment responders, reverted transcriptional signatures associated with CSU lesion phenotype to reflect nonlesional/HV expression levels; this is consistent with observed omalizumab‐mediated clinical improvement observed in patients with CSU. The gene expression of the lesional skin of patients with chronic spontaneous urticaria shows a distinct signature when compared to their nonlesional skin and the skin of healthy volunteers. The pattern of gene expression in the lesional skin of omalizumab‐treated patients are different than before treatment, but not in their nonlesional skin. In treatment responders, omalizumab treatment shows reverted transcriptional signatures associated with CSU lesion phenotype to reflect nonlesional/healthy volunteer expression levels consistent with observed clinical improvement. [ABSTRACT FROM AUTHOR]

Aerogen lactase exposure carries a risk for the development of allergic asthma and rhinitis; only a few occupationally affected patients have been reported. The authors report the results of allergy testing with employees of a lactase tablets manufacturing plant. The survey involved 13 workers, including a questionnaire, spirometry, basophil activation test (BAT), and skin prick tests (SPTs) with lactase and a panel of common aeroallergens. Furthermore, lactase-specific immunoglobulin E (IgE) antibodies were analyzed. Sensitization to lactase could be proven for 9 workers by SPT and BAT; specific IgE antibodies could be detected in serum samples of all sensitized. However, IgE levels ≥0.35 kU/L were only found in 4 sera. These data confirm that occupational exposure to lactase can induce IgE-mediated respiratory sensitization resulting in allergic diseases. Protective measures should thus be obligatory when working with lactase. [ABSTRACT FROM AUTHOR]

Proteinase-activated receptor-2 (PAR2) belongs to a new G protein-coupled receptor subfamily activated by serine proteinases. PAR2 has been demonstrated to play a role during inflammation and immune response in different tissues including the skin. We examined whether PAR2 is functionally expressed by cutaneous human primary skin mast cells (HPMC) and the human mast cell line 1 (HMC-1). Reverse transcription-polymerase chain reaction and FACS analysis show expression of PAR2 both at the RNA and protein level. HPMCs and HMC-1 also express PAR1, PAR3, and PAR4. Ca-mobilization studies demonstrate functional PAR2 expressed by human skin mast cells, as shown by natural and synthetic PAR2 agonists. PAR2 agonists induced histamine release from HPMC indicating a role of PAR2 in regulating inflammatory and immune responses by skin mast cells. Double-immunofluorescence staining reveals colocalization of PAR2 with tryptase in the majority of human skin mast cells. In conclusion, trypsin and tryptase as well as specific agonists for PAR2 were able to induce Ca2+ mobilization in HPMCs, and agonists of PAR2 induce the release of histamine from these cells. Thus, PAR2 may be an important regulator of skin mast cell function during cutaneous inflammation and hypersensitivity.Journal of Investigative Dermatology (2006) 126, 746–755. doi:10.1038/sj.jid.5700169; published online 9 February 2006 [ABSTRACT FROM AUTHOR]

Background: Plant profilins are important pan-allergens. They are responsible for a significant percentage of pollen-related allergies. Limited information is available about their involvement in the latex-fruit syndrome and the cross-reactivities between latex and pollen. We aimed to clone and express the Hevea brasiliensis latex profilin to investigate its allergological significance and serological cross-reactivities to profilins from plant foods and pollens. Methods: A DNA complementary to messenger RNA (cDNA) coding for the Hevea latex profilin, Hev b 8, was amplified by polymerase chain reaction from latex RNA. Recombinant (r)Hev b 8 was produced in Escherichia coli and used to screen sera from 50 latex- allergic health care workers (HCWs) with well-documented histories of food and pollen allergy and 34 latex-allergic spina bifida (SB) patients. The cross-reactivity of natural Hev b 8 and rHev b 8 with other plant profilins was determined by ELISA inhibition assays. A three-dimensional homology model of Hev b 8 was constructed based on known profilin structures. Results: The cDNA of Hev b 8 encoded a protein of 131 amino acids with a predicted molecular mass of 14 kD. Twelve of the 50 HCWs and 2 of the 34 SB patients were sensitized to Hev b 8. All Hev b 8-sensitized patients showed allergic symptoms to pollen or plant foods. Cross-reactivities between profilins of latex, pollen and plant food were illustrated by their ability to inhibit IgE binding to rHev b 8. Homology modeling of Hev b 8 yielded a structure highly similar to Bet v 2, the birch pollen profilin, with the most distinct differences located at the N-terminus. Conclusions: We conclude that primary sensitization to latex profilin in the majority of cases takes place via pollen or food profilins. Additionally, pollinosis and food-allergic patients with profilin-specific IgE can be at risk of developing latex allergy.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Natural rubber latex allergy is an IgE-mediated disease that is caused by proteins that elute from commercial latex products. A complementary DNA (cDNA) coding for Hev b 9, an enolase (2-phospho- d-glycerate hydrolyase) and allergen from latex of the rubber tree Hevea brasiliensis , was amplified by PCR. The PCR primers were designed according to conserved regions of enolases from plants. The obtained cDNA amplification product consisted of 1651 bp and encoded a protein of 445 amino-acid residues with a calculated molecular mass of 47.6 kDa. Sequence comparisons revealed high similarities of the Hevea latex enolase to mold enolases that have been identified as important allergens. In addition, the crucial amino-acid residues that participate in the formation of the catalytic site and the Mg2+ binding site of enolases were also conserved. Hevea latex enolase was produced as a recombinant protein in Escherichia coli with an N-terminal hexahistidyl tag, and purified by affinity chromatography. The yield amounted to 110 mg of purified Hev b 9 per litre of bacterial culture. The recombinant allergen bound IgE from latex, as well as mold-allergic patients, in immunoblot and ELISA experiments. The natural enolase was isolated from Hevea latex by (NH4 )2 SO4 precipitation and ion exchange chromatography. The natural and the recombinant (r)Hev b 9 showed equivalent enzymatic activity. Patients’ IgE-antibodies preincubated with rHev b 9 lost their ability to bind to natural (n) Hev b 9, indicating the identity of the B-cell epitopes on both molecules. Cross-reactivity with two enolases from Cladosporium herbarum and Alternaria alternata was determined by inhibition of IgE-binding to these enolases by rHev b 9. Therefore, enolases may represent another class of highly conserved enzymes with allergenic potentials. [ABSTRACT FROM AUTHOR]

IgE-mediated hypersensitivity to latex proteins present in health care products, particularly in latex gloves, has become an important public health problem in recent years. We purified natural Hev b 7, a 43-kDa patatin-like allergen from the latex of Hevea brasiliensis and determined several internal peptide sequences. A heterologous hybridization probe of a patatin gene of potato, to which these peptides could be aligned best, was used to screen a latex cDNA library. The cDNA encoded an acidic protein of 388 amino acids with a molecular mass of 42.9 kDa. The deduced amino acid sequence had 39-42 % identity to patatins from Solanum tuberosum. The purified recombinant Hev b 7 expressed in the yeast Pichia pastoris displayed, similarly to patatins from S. tuberosum, esterase activity. Both natural and recombinant Hev b 7 were recognized by IgE from sera of latex-sensitized allergic individuals. In contrast to patatins from S. tuberosum and Nicotiana tabacum, natural Hev b 7 lacked an N-terminal leader peptide for targeting to the endoplasmatic reticulum and was not glycosylated. These results establish the 43-kDa patatin-like protein as a latex allergen and raise the possibility of different cellular localization and function compared to S. tuberosum patatins. [ABSTRACT FROM AUTHOR]