Allergies, Volume 3, Issue 1 (March 2023) – 6 articles

The prevalence of allergic rhinitis is rising, and it is impacting children’s growth and quality of life. To uncover unconventional treatment modalities, research was carried out to clarify the significance of novel components in the pathophysiology of allergic rhinitis. One of these elements was gut microbiota, which plays a crucial role in the development and evolution of allergic disorders. Specifically, dysbiosis, defined as impaired microbiota composition, characterizes allergic disorders. In light of this concept, probiotics (beneficial bacteria) may restore gut dysbiosis, rebalance the immune response, and indirectly influence the clinical course of allergic diseases. In this article, we discussed the role of the gut–lung axis in children and reported on new findings. We also reviewed the most relevant studies about probiotics in patients with allergic rhinitis. Full article

Background: The natural history of immunoglobulin (Ig) E-mediated diseases in preterm infants is still elusive. We aimed at developing a non-invasive tool for detecting specific IgE (sIgE) and eosinophil-derived neurotoxin (EDN) in neonatal fecal samples and evaluating its predictive value for the development of IgE-mediated diseases during the first year of life. Methods: We developed a stool extraction protocol, followed by freeze-drying and solubilization. The sIgEs were investigated in neonatal fecal samples from 21 preterm infants with a 300-allergen multiplex and confirmed by a capillary Western blot with a nano-immunoassay. EDN concentration was used to investigate the local eosinophilic component. Results: The multiplexed allergen assay detected sIgE in all of the samples. A Western blot was used to confirm the results. The frequency and levels of sIgE in the neonatal fecal samples differed between the infants who developed IgE-mediated diseases and the controls. Allergen specificity was associated with the development of cow’s milk allergy (CMA) and asthma. The development of CMA was predicted by the sIgE response to milk proteins (sensitivity was 88%; specificity was 78%). The EDN levels predicted the development of IgE-mediated diseases (sensitivity was 100%; specificity was 75%). Conclusion: The non-invasive investigation of neonatal fecal sIgE is a promising tool for predicting the subsequent development of IgE-mediated diseases. Clinical Implications: The non-invasive sIgE and EDN profiling of neonatal fecal samples from preterm infants can predict the development of IgE-mediated diseases. Full article

Celiac peptide-generating α- and γ-gliadins consist of a disordered N-terminal domain extended by an α-helical-folded C-terminal domain. Celiac peptides, primarily located along the disordered part of α- and γ-gliadin molecules, are nicely exposed and directly accessible to proteolytic enzymes occurring in the gastric (pepsin) and intestinal (trypsin, chymotrypsin) fluids. More than half of the potential celiac peptides identified so far in gliadins exhibit cleavage sites for pepsin. However, celiac peptides proteolytically truncated by one or two amino acid residues could apparently retain some activity toward HLA-DQ2 and HLA-DQ8 receptors in docking experiments. Together with the uncleaved peptides, these still active partially degraded CD peptides account for the incapacity of the digestion process to inactivate CD peptides from gluten proteins. In contrast, sourdough fermentation processes involve other proteolytic enzymes susceptible to the deep degradation of celiac peptides. In particular, sourdough supplemented by fungal prolyl endoproteases enhances the degrading capacities of the sourdough fermentation process toward celiac peptides. Nevertheless, since tiny amounts of celiac peptides sufficient to trigger deleterious effects on CD people can persist in sourdough-treated bread and food products, it is advisable to avoid consumption of sourdough-treated food products for people suffering from celiac disease. As an alternative, applying the supplemented sourdough process to genetically modified low gluten or celiac-safe wheat lines should result in food products that are safer for susceptible and CD people. Full article

Plants are essential for humans as they serve as a source of food, fuel, medicine, oils, and more. The major elements that are utilized for our needs exist in storage organs, such as seeds. These seeds are rich in proteins, show a broad spectrum of physiological roles, and are classified based on their sequence, structure, and conserved motifs. With the improvements to our knowledge of the basic sequence and our structural understanding, we have acquired better insights into seed proteins and their role. However, we still lack a systematic analysis towards understanding the functional diversity associated within each family and their associations with allergy. This review puts together the information about seed proteins, their classification, and diverse functional roles along with their associations with allergy. Full article

The present work was aimed at identifying the IgE-binding epitopic regions on the surface of the Cup s 3 allergen from the common cypress Cupressus sempervirens, that are possibly involved in the IgE-binding cross-reactivity reported between Cupressaceae species. Three main IgE-binding epitopic regions were mapped on the molecular surface of Cup s 3, the PR-5 thaumatin-like allergen of common cypress Cupressus sempervirens. They correspond to exposed areas containing either electropositive (R, K) or electronegative (D, E) residues. A coalescence occurs between epitopes #1 and #2, that creates an extended IgE-binding regions on the surface of the allergen. Epitope #3 contains a putative N-glycosylation site which is actually glycosylated and could therefore comprise a glycotope. However, most of the allergenic potency of Cup s 3 depends on non-glycosylated epitopic peptides. The corresponding regions of thaumatin-like allergens from other closely related Cupressaceae (Cryptomeria, Juniperus, Thuja) exhibit a very similar conformation that should account for the IgE-binding cross-reactivity observed among the Cupressaceae allergens. Full article

Probiotics are an attractive target for reducing the incidence of allergic disease. Bacillus subtilis is a gut-associated probiotic bacteria that can suppress allergic lung disease; however, it is not clear for how long this protection lasts. We exposed C57Bl/6 mice to B. subtilis via oral gavage and challenged them with intranasal house-dust mite for up to 8 weeks. We found that B. subtilis treatment was able to provide protection from eosinophil infiltration of the airways for 3 weeks. This loss of protection correlated with an increase in the eosinophil chemoattractant CCL24. Additionally, we demonstrate that B. subtilis treatment altered the bacterial composition by increasing the phylum Bacteroidetes and Verrucomicorbiota. The phylum Verrucomicorbiota was reduced in B. subtilis-treated mice at 8 weeks when protection was lost. These results support B. subtilis as a prophylactic for preventing the production of allergic lung disease and highlights that protection can last up to 3 weeks. This work also expands our understanding of how B. subtilis mediates protection and that in addition to modifying the immune system it is also altering the host microbiota. Full article