Allergic Poly-sensitization Research Articles

Increased Exacerbation Burden in Allergic Polysensitized Patients with Moderate to Severe Asthma

Using a machine learning algorithm, we recently reported allergic poly-sensitization (APS) clusters based on ImmunoCAP® results as a newly recognized severity marker in adult urban asthmatics. APS clusters, based on numbers of positive allergen sensitizations and allergen-specific IgE levels can predict pulmonary function decline, total IgE levels and eosinophilia. Also, we found “superclusters” (cluster groupings) that tracked patients with either predominately seasonal or perennial allergen sensitizations.

Allergic Polysensitization Clusters: Newly Recognized Severity Marker in Urban Asthmatic Adults

Introduction: While reliable, quantitative in vitro testing for sensitivity to aeroallergens has been available for decades, such information has largely been ignored in clustering analyses of asthma. Our aim is to explore allergic polysensitization as a possible marker of asthma severity and, as such, to be considered as an integral marker in future asthma clustering analyses. Methods: We constructed a database of sensitizations to the 25 aeroallergens in our geographic area (zone 1, Northeastern US) using the ImmunoCAP® in vitro assay. We used the Scikit-Learn® machine learning library for model-based clustering to identify allergic polysensitization clusters. Clusters were compared for differences in common office-based clinical markers of asthma. Results: The database consisted of 509 patients. Unbiased machine learning identified ten clusters of increasing allergic polysensitization of varying sizes (n = 1–339) characterized by significant increases in mean serum immunoglobulin E (p < 0.001), peripheral blood eosinophil count (p < 0.001), and D_LCO (p = 0.02). There was a significant decline in mean age at presentation (p < 0.001), FEV₁/FVC (p = 0.01), and FEF_25-75 (p = 0.002) with increasing allergic polysensitization. Finally, we identified two divergent paths for the poly-atopic march, one driven by perennial and the other by seasonal allergens. Conclusion: This pilot study showed that allergic polysensitization, using readily available qualitative and quantitative in vitro sensitization data, largely ignored in cluster analyses to date, may add further clinical precision in cluster analyses of asthma. We suggest the methods used here can be applied and tested using larger databases and aeroallergens present in diverse geographic regions.

Pre- and Neonatal Imprinting on Immunological Homeostasis and Epithelial Barrier Integrity by Escherichia coli Nissle 1917 Prevents Allergic Poly-Sensitization in Mice.

A steady rise in the number of poly-sensitized patients has increased the demand for effective prophylactic strategies against multi-sensitivities. Probiotic bacteria have been successfully used in clinics and experimental models to prevent allergic mono-sensitization. In the present study, we have investigated whether probiotic bacteria could prevent poly-sensitization by imprinting on the immune system early in life. We used two recombinant variants of probiotic Escherichia coli Nissle 1917 (EcN): i) EcN expressing birch and grass pollen, poly-allergen chimera construct (EcN-Chim), and ii) an “empty” EcN without allergen expression (EcN-Ctrl). Conventional mice (CV) were treated with either EcN-Chim or EcN-Ctrl in the last week of the gestation and lactation period. Gnotobiotic mice received one oral dose of either EcN-Chim or EcN-Ctrl before mating. The offspring from both models underwent systemic allergic poly-sensitization and intranasal challenge with recombinant birch and grass pollen allergens (rBet v 1, rPhl p 1, and rPhl p 5). In the CV setting, the colonization of offspring via treatment of mothers reduced allergic airway inflammation (AAI) in offspring compared to poly-sensitized controls. Similarly, in a gnotobiotic model, AAI was reduced in EcN-Chim and EcN-Ctrl mono-colonized offspring. However, allergy prevention was more pronounced in the EcN-Ctrl mono-colonized offspring as compared to EcN-Chim. Mono-colonization with EcN-Ctrl was associated with a shift toward mixed Th1/Treg immune responses, increased expression of TLR2 and TLR4 in the lung, and maintained levels of zonulin-1 in lung epithelial cells as compared to GF poly-sensitized and EcN-Chim mono-colonized mice. This study is the first one to establish the model of allergic poly-sensitization in gnotobiotic mice. Using two different settings, gnotobiotic and conventional mice, we demonstrated that an early life intervention with the EcN without expressing an allergen is a powerful strategy to prevent poly-sensitization later in life.

Ole e 3, a Candidate for in vivo Diagnosis of Polcalcin Sensitization

Introduction: Polcalcins belong to the family of calcium-binding proteins. They are ubiquitous in the plant kingdom and highly conserved, which leads to these panallergens showing a high degree of inter-cross-reactivity. They are responsible for allergic polysensitization, and therefore, their diagnosis is necessary for correct selection of immunotherapy. The objectives were to develop a method to purify native polcalcin with intact allergenic properties and to validate its use for diagnosis of polcalcin sensitization. Methods: Ole e 3 was purified by immunoaffinity chromatography using anti-rChe a 3 polyclonal antibodies and identified by mass spectrometry. Calcium-binding assays were performed in immunoblot and ELISA assays. Diagnostic capacity of Ole e 3 was analyzed by ELISA and compared to ImmunoCAP with sera from a pollen-sensitized population. Cross-reactivity with other polcalcins was investigated by ImmunoCAP inhibition. Results: Immunogenicity of purified Ole e 3 was not affected by the addition of calcium. However, the presence of a calcium chelator agent completely inhibited IgG binding by immunoblot and produced a 32.3% reduction in IgE binding by ELISA. Ole e 3 enabled diagnosis of polcalcin-sensitized patients, and a good correlation was revealed with ImmunoCAP. A 50% inhibition in IgE binding was obtained with 2.8 ng of Ole e 3 for rBet v 4 and 3.9 ng for rPhl p 7. Discussion/Conclusion: Native Ole e 3 was purified by maintaining its allergenic properties. This innovative method enables obtaining this active native allergen to be used for in vivo diagnosis of polcalcin sensitization.

Staphylococcus Aureus Enterotoxin Sensitization Is Associated With Allergic Poly-sensitization and Allergic Multimorbidity in Adolescents

M Sorensen, C Klingenberg, M Wickman. Allergy. 2017;72(10):1548–1555 In the authors’ previous study (Tromso Study Fit Futures 2) an association was found between nasal Staphylococcus aureus carriage and allergic morbidity in adolescent patients. The authors sought to determine the relationship between S aureus enterotoxin (SE) sensitization with both allergic polysensitization and allergic disease. A total of 1208 high school students were invited to partake in the study, and 868 (71.9%) ultimately participated. Students had been previously recruited in 2010–2011 to the authors’ initial cohort and some had participated in the original …

Correction: E. coli Nissle 1917 is a safe mucosal delivery vector for a birch-grass pollen chimera to prevent allergic poly-sensitization.

Following the publication of this article, the authors have requested that the Acknowledgements section be amended to include the financing source of the study. The correct Acknowledgments should be as follows: We gratefully acknowledge funding from the Austrian Science Fund SFB F46 and DK MCCA W1248-B30, OeAD-GmbH grants (FR13/2016) and from the Amadeus partnership Hubert Curein French and Austrian program. We thank the BioImaging Center of Lille (Frank Lafont) for the use of the IVIS Lumina XR. We gratefully thank Katharina Ambroz, Elke Korb, Karin Baier, Erika Garner-Spitzer, Joshua Tobias, Gwenaëlle Verbrugghe, and Jéremy Desramaut for their technical assistance and helpful discussions.

E. coli Nissle 1917 is a safe mucosal delivery vector for a birch-grass pollen chimera to prevent allergic poly-sensitization

Allergic poly-sensitization affects a large number of allergic patients and poses a great challenge for their treatment. In this study we evaluated the effects of the probiotic Escherichia coli Nissle 1917 (EcN) expressing a birch and grass pollen allergen chimera ‘Bet v 1, Phl p 1 and Phl p 5’ (EcN-Chim) on allergy prevention after oral or intranasal application in poly-sensitized mice. In contrast to oral application, intranasal pretreatment with EcN-Chim prior to poly-sensitization led to a significant reduction of lung inflammation (eosinophils, IL-5, and IL-13 in bronchoalveolar lavage) along with suppressed levels of allergen-specific serum IgE. The suppression was associated with increased levels of allergen-specific IgA in lungs and serum IgG2a along with increased Foxp3, TGF-β, and IL-10 mRNA in bronchial lymph nodes. In vitro EcN induced high levels of IL-10 and IL-6 in both lung and intestinal epithelial cells. Importantly, using in vivo imaging techniques we demonstrated that intranasally applied EcN do not permanently colonize nose, lung, and gut and this strain might therefore be a safe delivery vector against allergy in humans. In conclusion, our data show that intranasal application of recombinant EcN expressing a multiallergen chimera presents a novel and promising treatment strategy for prevention of allergic poly-sensitization.

Factors reducing omalizumab response in severe asthma

BackgroundDespite adding Omalizumab to conventional therapy, several severe asthmatics still show poor disease control. We investigated the factors that may affect a reduced Omalizumab response in a large population of severe asthmatics. Methods340 patients were retrospectively evaluated. FEV1%, FVC%, Asthma Control Test (ACT), fractional exhaled nitric oxide (FENO), possible step-downs/step-ups of concomitant therapies, exacerbations, disease control levels, ICS doses and SABA use, observed at the end of treatment, were considered as a response to Omalizumab. ResultsAge was an independent risk factor for a reduced response concerning FEV1%, FVC%, ACT and for a lower asthma control. Obesity (vs normal weight) was a determinant condition for exacerbations (OR:3.114[1.509–6.424], p = 0.002), for a disease partial/no control (OR:2.665[1.064–6.680], p = 0.036), for excessive SABA use (OR:4.448[1.837–10.768], p = 0.002) and for an unchanged/increased level of concomitant asthma medications. Furthermore, obesity also reduced the response in FEV1 (β = −6.981,p = 0.04), FVC (β = −11.689,p = 0.014) and ACT (β = −2.585, p = 0.027) and was associated with a higher FENO level (β = 49.045,p = 0.040). Having at least one comorbidity was a risk factor for exacerbations (OR:1.383[1.128–1.697], p = 0.008) and for an ACT <20 (OR:2.410[1.071–3.690], p = 0.008). Specifically, chronic heart disease was associated with both a lower ACT and FVC% whereas gastroesophageal reflux with a partial/no asthma control. Nasal polyps were a predisposing factor leading both to exacerbations and to the use of higher inhaled corticosteroids doses. Moreover, smoking habits, pollen or dog/cat dander co-sensitizations may negatively influence Omalizumab response. ConclusionAge, obesity, comorbidities, smoking habits, nasal polyps, allergic poly-sensitization might reduce Omalizumab effectiveness independently to other asthma-influencing factors.

Staphylococcus aureus enterotoxin sensitization is associated with allergic poly-sensitization and allergic multimorbidity in adolescents.

Staphylococcus aureus (S.aureus) carriage and sensitization to S.aureus enterotoxins (SEs) have been associated with allergic diseases. From the Tromsø Study Fit Futures 2, we have previously shown an association between S.aureus carriage and severe allergic disease and allergic multimorbidity. However, the role of S.aureus carriage and SE sensitization on allergic multimorbidity and allergic sensitization is unclear. To study associations of both nasal S.aureus carriage and SE sensitization to allergic disease and allergic sensitization. A cross-sectional study of a school-based cohort in late adolescence (aged 18-19years: The Tromsø Study Fit Futures 2). Self-reported allergic diseases were assessed using the Mechanisms of the Development of ALLergy questionnaire (MeDALL). Participants were tested for nasal S.aureus carriage, serum total IgE and specific IgE to SEs, and food and inhalant allergens. A total of 868 participants were studied. Sensitization to at least one food or inhalant allergen was found in 319 of 765 (41.7%), and to at least one SE in 173 of 656 (26.2%) participants. SE sensitization, but not S.aureus carriage, was associated with poly-sensitization to food and inhalant allergens. SE-sensitized participants had higher median specific IgE to inhalant allergens (41.4 kUA /L, IQR 10.1-118.4) compared to non-SE-sensitized participants (18.0 kUA /L, IQR 5.5-48.6, P=.004), but not to food allergens. SE sensitization was associated with allergic multimorbidity. Sensitization to SEs may play a role in the development of allergen poly-sensitization and allergic multimorbidity.

Purification and immunochemical characterization of Pla l 2, the profilin from Plantago lanceolata.

Profilins are small actin-binding proteins found in eukaryotes and involved in cell development, cytokinesis, membrane trafficking, and cell motility. From an allergenic point of view, profilins are panallergens usually involved in allergic polysensitization, although they are generally recognized as minor allergens. The objectives of this study were to identify and characterize the profilin from Plantago lanceolata pollen and to investigate the cross-reactivity between profilins from different pollen allergenic sources. Profilins from P. lancelolata (Pla l 2) and palm tree pollen (Pho d 2) were purified by affinity chromatography, deeply characterized and identified by mass spectrometry. Pla l 2 allergenicity was confirmed by immunoblot with serum samples from a patient population sensitized to profilin. Immunoblot inhibition was performed to study IgG reactivity between different pollen profilins. IgE cross-reactivity was demonstrated by ImmunoCAP inhibition. Pla l 2 is the second P. lanceolata allergen included in the IUIS Allergen Nomenclature database. Four peptides from purified Pla l 2 were identified with percentages of homology with other pollen profilins between 73 and 86%. Eighty-six percent (21/24) of the patient population recognized Pla l 2. The allergenic relatedness between Pla l 2, Pho d 2 and six pollen profilins was confirmed, and IgE cross-reactivity of Pla l 2 with rBet v 2 and rPhl p 12 was demonstrated. Pla l 2 is the profilin from P. lanceolata. The demonstrated allergenicity of this protein and its cross-reactivity with other pollen profilins support its use in profilin diagnostic assays.

Distinctive anti-allergy properties of two probiotic bacterial strains in a mouse model of allergic poly-sensitization

We compared the immunomodulatory properties of Bifidobacterium longum NCC 3001 and Lactobacillus paracasei NCC 2461 in a mouse model of poly-sensitization to birch and grass pollen allergens. Mucosal application of both strains at the time of sensitization and challenge led to significant suppression of airway inflammation and down-regulated allergen-specific immune responses. In contrast, in the mice treated with probiotics prior to sensitization and challenge, only B. longum displayed protective effects. Our findings stress that the choice of probiotic strain and the timing of the application are crucial for tolerance induction. Furthermore, this is the first demonstration of anti-allergic effects of probiotic bacteria in poly-sensitized mice.

Asthma severity in childhood, untangling clinical phenotypes*

Assessment of childhood asthma severity and asthma control encompasses heterogeneous clinical presentations. The relationship between patterns of asthma symptoms and objective measurements is poorly defined in paediatric asthma. This study includes 115 asthmatic schoolchildren, of which 31 were at inclusion defined as Problematic severe asthma because of inadequate asthma control in the presence of high-dose inhaled corticosteroid (HD-ICS) treatment and at least one other asthma controller drug. Two partially overlapping clinical outcomes were defined irrespective of severity classification (Exacerbations and Chronic persistent asthma) in patients with uncontrolled asthma. The same symptom criteria were used as for Problematic severe asthma, but disregarding current medication. Lung function, exhaled nitric oxide (FE(NO)), bronchial hyperresponsiveness, allergic sensitization and Quality of life (QoL) in the symptom subgroups were compared to children with well-controlled asthma. Multifactor analysis was performed to assess the relative explanatory power of clinical asthma presentations and of HD-ICS treatment on objective measurements. Whereas children included in the Exacerbations subgroup had objective features similar to patients with well-controlled asthma, the Chronic persistent asthma subgroup demonstrated significantly reduced lung function, increased immunoglobin E, allergic poly-sensitization and impaired QoL, similar to that in patients pre-defined as Problematic severe asthma. The presence of chronic asthma symptoms was a significant explanatory factor for reduced lung function, QoL and increased FE(NO) in multifactor analysis. Differences in objective measurements suggest that children with Chronic persistent asthma and those who are symptomatic predominantly during exacerbations may represent distinct phenotypes of childhood asthma with different clinical prognoses.

Interferon‐gamma and IL‐10 may protect from allergic polysensitization in children: preliminary evidence

A functional defect of T regulatory cells (Treg) has been proposed as pathogenic mechanism of allergic reaction. Polysensitization is a common feature of allergic patients. It was to investigate the possible role of Treg-Th1 cytokines, in the development of new sensitizations in childhood. Forty monosensitized (MS) children with allergic rhinitis were evaluated and followed-up for 2 years. New sensitizations were investigated. IL-10 and IFN-gamma were evaluated in in vitro experiments. Children remaining MS showed significant higher production of both IL-10 and IFN-gamma. This preliminary study provided evidence that IL-10 and IFN-gamma production could be defective in allergic children prone to develop polysensitization.

Sublingual immunotherapy in children with allergic polysensitization

Polysensitization is quite frequent in allergic children and may cause difficulties for the allergist in prescribing allergen-specific immunotherapy. This study aimed at evaluating the clinical effectiveness of 1 year of sublingual immunotherapy (SLIT) in a cohort of Italian allergic children with polysensitization. This open study was performed on 51 polysensitized children (34 boys; mean age, 11.8 years; range, 5.2-17.7 years) with allergic rhinitis and/or mild to moderate asthma. All of them were treated with SLIT for 1 year. The kind and the number of prescribed allergen extracts, the type of diagnosis, the severity of symptoms, and the use of drugs were evaluated at baseline and after 1 year. The adverse events to SLIT were also evaluated. Forty-two children were treated with a single extract, four with two different extracts and three with a mix of allergens. SLIT treatment induced a significant reduction in the number of sensitizations (p = 0.018); significant improvement of allergic rhinitis classification and severity; significant reduction of ocular, nasal, and bronchial symptoms (p < 0.01 for all); and drugs use (p < 0.01 for all drugs). No systemic reactions to SLIT were observed. This open study provides evidence that polysensitization is not an obstacle for prescribing SLIT in polysensitized children. Indeed, SLIT efficacy on clinical parameters is significant after 1 year and the therapy is safe.

Intranasal tolerance induction with polypeptides derived from 3 noncross-reactive major aeroallergens prevents allergic polysensitization in mice

Specific immunotherapy is less effective in patients with multiple allergic sensitizations compared with monosensitized patients. We therefore established a mouse model of polysensitization to the major birch and timothy grass pollen allergens to test whether allergic polysensitization can be prevented by multiple allergen application via the mucosal route. Female BALB/c mice were immunized intraperitoneally with recombinant (r) Bet v 1, rPhl p 1, and rPhl p 5. For intranasal tolerance induction, a mixture of the complete allergens was compared with allergen-derived immunodominant peptides applied either as a mixture or as a synthetic hybrid peptide composed of the T-cell epitopes of the 3 allergens. Intranasal application of the mixture of the complete allergen molecules did not prevent polysensitization to the same allergens. In contrast, pretreatment with a mixture of the immunodominant peptides or the hybrid peptide led to significantly reduced allergen-specific IgE responses in sera, IL-4 production in vitro, and suppressed airway inflammation. TGF-beta mRNA levels did not change, and IL-10 production was significantly suppressed after the pretreatment. The fact that the reduction of IL-10 was not abrogated after IL-10 receptor neutralization and that tolerance was not transferable with splenocytes indicates that the suppression of T(H)2 responses in polysensitized mice might not be mediated by immunosuppressive cytokines. Our study demonstrates that it is possible to suppress allergic immune responses simultaneously to several clinical important allergens. Thus, mucosal coapplication of selected peptides/hybrid peptides could be the basis of a mucosal polyvalent vaccine to prevent multiple sensitivities in atopic patients.