Effects of extraction buffer on the solubility and immunoreactivity of the pacific oyster allergens

Despite recent technological advances, novel allergenic protein discovery is limited by their low abundance, often due to specific physical characteristics restricting their recovery during the extraction process from various allergen sources. In this study, eight different extraction buffers were compared for their ability to recover proteins from Pacific oyster (Crassostrea gigas). The protein composition was investigated using high resolution mass spectrometry. The antibody IgE-reactivity of each extract was determined using a pool of serum from five shellfish-allergic patients. Most of the investigated buffers showed good capacity to extract proteins from the Pacific oyster. In general, a higher concentration of proteins was recovered using high salt buffers or high pH buffers, subsequently revealing more IgE-reactive bands on immunoblotting. In contrast, low pH buffers resulted in a poor protein recovery and reduced IgE-reactivity. Discovery of additional IgE-reactive proteins in high salt buffers or high pH buffers was associated with an increase in allergen abundance in the extracts. In conclusion, increasing the ionic strength and pH of the buffer improves the solubility of allergenic proteins during the extraction process for oyster tissue. This strategy could also be applied for other difficult-to-extract allergen sources, thereby yielding an improved allergen panel for increased diagnostic efficiency

Induction of IgG2 and IgG4 B-cell memory following sublingual immunotherapy for ryegrass pollen allergy

Background: While treatment for atopic rhinitis is aimed mostly to relieve symptoms, only allergen-specific immunotherapy (AIT) is targeted to modify the natural history of allergic diseases. This results in sustained clinical tolerance, even when treatment has stopped. The immunomodulatory effects of AIT are attributed mainly to increased regulatory T-cell function and increased allergen-specific IgG4, yet little is known about the effect on the memory B-cell compartment. Objective: We aimed to examine the effects of AIT on the IgE- and IgG subclass-expressing memory B cells. Methods: We recruited 29 patients with atopic seasonal rhinoconjunctivitis and performed a longitudinal analysis of the peripheral immune compartment before, during, and after sublingual immunotherapy (SLIT) for allergy to temperate grass pollen, predominantly to ryegrass pollen (RGP; Lolium perenne). Using flow cytometry on peripheral blood mononuclear cells and serum immunoassays, we analyzed the effects of a 4 months preseasonal treatment regimen comprising two or three courses in consecutive years on circulating IgE+ and IgG+ memory B cells and allergen-specific Ig levels. Results: SLIT increased RGP-specific serum IgG2 and IgG4, as well as the frequencies of IgG2 + and IgG4 + memory B cells, whereas no effect was observed on the IgE+ memory B-cell compartment. Furthermore, SLIT enhanced proportions of regulatory T cells specific to RGP. These changes were associated with clinical improvement. Conclusion: Our data provide evidence for immunological effects of SLIT on B-cell memory. Skewing responses toward IgG2 and IgG4 subclasses might be a mechanism to suppress IgE-mediated allergic responses

Development and validation of combined symptom‐medication scores for allergic rhinitis*

Background: Validated combined symptom-medication scores (CSMSs) are needed to investigate the effects of allergic rhinitis treatments. This study aimed to use real-life data from the MASK-air® app to generate and validate hypothesis- and data-driven CSMSs. Methods: We used MASK-air® data to assess the concurrent validity, test-retest reliability and responsiveness of one hypothesis-driven CSMS (modified CSMS: mCSMS), one mixed hypothesis- and data-driven score (mixed score), and several data-driven CSMSs. The latter were generated with MASK-air® data following cluster analysis and regression models or factor analysis. These CSMSs were compared with scales measuring (i) the impact of rhinitis on work productivity (visual analogue scale [VAS] of work of MASK-air® , and Work Productivity and Activity Impairment: Allergy Specific [WPAI-AS]), (ii) quality-of-life (EQ-5D VAS) and (iii) control of allergic diseases (Control of Allergic Rhinitis and Asthma Test [CARAT]). Results: We assessed 317,176 days of MASK-air® use from 17,780 users aged 16-90 years, in 25 countries. The mCSMS and the factor analyses-based CSMSs displayed poorer validity and responsiveness compared to the remaining CSMSs. The latter displayed moderate-to-strong correlations with the tested comparators, high test-retest reliability and moderate-to-large responsiveness. Among data-driven CSMSs, a better performance was observed for cluster analyses-based CSMSs. High accuracy (capacity of discriminating different levels of rhinitis control) was observed for the latter (AUC-ROC = 0.904) and for the mixed CSMS (AUC-ROC = 0.820). Conclusion: The mixed CSMS and the cluster-based CSMSs presented medium-high validity, reliability and accuracy, rendering them as candidates for primary endpoints in future rhinitis trials

The ARIA-MASK-air® approach

Funding Information: The authors thank Ms Véronique Pretschner for submitting the paper. MASK‐air has been supported by Charité Universitätsmedizin Berlin, EU grants (EU Structural and Development Funds Languedoc Roussillon and Region PACA; POLLAR: EIT Health; Twinning: EIP on AHA; Twinning DHE: H2020; Catalyse: Horizon Europe) and educational grants from Mylan‐Viatris, ALK, GSK, Novartis, Stallergènes‐Greer and Uriach. None for the study. ® Publisher Copyright: © 2023 The Authors. Clinical and Translational Allergy published by John Wiley & Sons Ltd on behalf of European Academy of Allergy and Clinical Immunology.MASK-air®, a validated mHealth app (Medical Device regulation Class IIa) has enabled large observational implementation studies in over 58,000 people with allergic rhinitis and/or asthma. It can help to address unmet patient needs in rhinitis and asthma care. MASK-air® is a Good Practice of DG Santé on digitally-enabled, patient-centred care. It is also a candidate Good Practice of OECD (Organisation for Economic Co-operation and Development). MASK-air® data has enabled novel phenotype discovery and characterisation, as well as novel insights into the management of allergic rhinitis. MASK-air® data show that most rhinitis patients (i) are not adherent and do not follow guidelines, (ii) use as-needed treatment, (iii) do not take medication when they are well, (iv) increase their treatment based on symptoms and (v) do not use the recommended treatment. The data also show that control (symptoms, work productivity, educational performance) is not always improved by medications. A combined symptom-medication score (ARIA-EAACI-CSMS) has been validated for clinical practice and trials. The implications of the novel MASK-air® results should lead to change management in rhinitis and asthma.publishersversionpublishe

Immunogenic Protein Pas N 1 from Bahia Grass Pollen

The present invention relates generally to novel recombinant polypeptides of Bahia grass pollen and to genetic sequences encoding same. More particularly, the present invention is directed to Pas n 1 polypeptides and derivatives, and fragments thereof and genetic sequences encoding same. The molecules of the present invention are useful in a range of therapeutic, prophylactic and diagnostic applications including, but not limited to, applications in the context of conditions characterised by an aberrant, inappropriate or otherwise unwanted immune response to the Bahia grass pollen

Allergen immunotherapy: Current and new therapeutic strategies

Allergen-specific immunotherapy (SIT) involves the administration of gradually increasing amounts of an allergen extract to reduce clinical symptoms of allergy. Well-controlled clinical trials have demonstrated the efficacy of SIT in the treatment of allergic diseases, including rhinoconjunctivitis and asthma, and best practice protocols have been established. Nevertheless, application of this potentially curative treatment is restricted, largely due to the risk of serious adverse events, especially in asthmatics. Although efficacy is high for venom-induced allergy, success rates for the more common aeroallergen-induced disease range from 60 to 80% depending on the allergen. The practice of SIT is currently being refined following major advances in our knowledge of basic immune mechanisms. In particular, new T cell-targeted strategies are being explored with the awareness of the pivotal role allergen-specific T cells play in initiating and regulating the immune response to allergens. Current SIT induces decreased IgE class switching and eosinophil activation by downregulating production of the T helper (Th) 2-type cytokines interleukin (IL)-4 and IL-5. Therefore, allergen preparations that have ablated IgE binding while retaining T cell reactivity should still be clinically effective but have substantially improved safety. These approaches include the use of small peptides based on dominant T cell epitopes of allergens and chemically modified or recombinant allergen molecules. Both approaches have already been tested, with promising results, in animal models; peptide immunotherapy has been shown effective in clinical trials. Defined hypoallergenic molecules or peptides offer ease of standardization in addition to efficacy and safety and will result in more widespread use of SIT in clinical practice. Elucidation of mechanisms for downregulating Th2-predominant responses to allergen by SIT will enable the development of laboratory assays for monitoring clinical efficacy