Polymorphisms in Cha o 1 and Cha o 2, major allergens of Japanese cypress (Chamaecyparis obtusa) pollen from a restricted region in Japan

Japanese cedar pollinosis is a major seasonal allergy in Japan, and Japanese cypress pollinosis is a growing concern because the cypress pollen season follows the cedar pollen season and cross-reactivity among allergens occurs between these closely related species. Allergens purified from pollen under unspecified collecting conditions can potentially heterogenous allergens profiles and batch to batch variability, and amino acid sequence variants in allergens possibly exist among trees. Polymorphisms have not been investigated for the cypress pollen major allergens, Cha o 1 and Cha o 2. Our aim was to examine the homogeneity of allergen amino acid sequences. DNA sequences of Cha o 1 and Cha o 2 from pollen collected from Chiba and Ibaraki prefectures and from needles of 47 plus trees located at seed orchards in Chiba Prefecture were examined by amplicon sequencing and amino acid substitutions were deduced. Sequence analysis of the pollen samples revealed that eight and seven residues of Cha o 2 were polymorphic, respectively. Thirteen residues in Cha o 2, including those residues identified in pollen, were deduced to be polymorphic for the plus trees. Cha o 2 expressed by the 47 plus trees included amino acid differences when compared with that of isoallergen Cha o 2.0101. No substitution was deduced in Cha o 1 for pollen taken from the two prefectures. One conservative amino acid substitution was deduced in Cha o 1 for the plus trees. Of the 47 plus trees examined, 38 were deduced to express only the isoallergen Cha o 1.0101 isoform, whereas eight trees were heterozygous and a single tree was homozygous for the non-synonymous mutation, which indicates relative uniformity of Cha o 1. Cha o 2 was found to be a heterogeneous allergen which suggests that studies using pollen from different trees may not give the same results.

Reduced production of the major allergens Bla g 1 and Bla g 2 in Blattella germanica after antibiotic treatment

Purpose Allergens present in the feces or frass of cockroaches can cause allergic sensitization in humans. The use of fecal and frass extracts for immunotherapy has been previously investigated but has not yet been fully standardized. Here, we treated cockroaches with ampicillin to produce extracts with reduced amounts of total bacteria. Methods We performed targeted high-throughput sequencing of 16S rDNA to compare the microbiomes of ampicillin-treated and untreated (control) cockroaches. RNA-seq was performed to identify differentially expressed genes (DEGs) in ampicillin-treated cockroaches. Results Analysis of the microbiome revealed that alpha diversity was lower in the ampicillin-treated group than in the control group. Beta diversity analysis indicated that ampicillin treatment altered bacterial composition in the microbiome of cockroaches. Quantitative polymerase chain reaction revealed that almost all bacteria were removed from ampicillin-treated cockroaches. RNA-seq analysis revealed 1,236 DEGs in ampicillin-treated cockroaches (compared to untreated cockroaches). Unlike bacterial composition, the DEGs varied between the two groups. Among major allergens, the expression of Bla g 2 decreased significantly in ampicillin-treated cockroaches (compared to untreated group). Conclusions In this study, the reduced level of allergens observed in cockroaches may be related to lower amounts of total bacteria caused by treatment with antibiotics. It is possible to make a protein extract with few bacteria for use in immunotherapy.

Helminth infection induces non-functional sensitization to house dust mites

Background IgE characterizes the humoral response of allergic sensitization but less is known about what modulates its function and why some patients present clinical symptoms for a given IgE level and others do not. An IgE response also occurs during helminth diseases, independently of allergic symptoms. This response could be a model of non-functional IgE. Objective To study the IgE response against environmental allergens induced during natural helminth infection. Methods In 28 non allergic subjects from the periphery of Ho Chi Minh city with (H+, n = 18) and without helminth infection (H-, n = 10), we measured IgE and IgG4 against several components of Dermatophagoïdes pteronyssinus (Dpt) and Ascaris (a marker of immunization against nematodes), and determined the IgE component sensitization profile using microarray ISAC biochips. The functional ability of IgE to induce degranulation of cultured mast cells was evaluated in the presence of Dpt. Results Non allergic H+ subjects exhibited higher levels of IgE against Dpt compared to H- subjects. Dpt IgE were not functional in vitro and did not recognize usual Dpt major allergens. IgE recognized other component allergens that belong to different protein families, and most were glycosylated. Depletion of IgE recognizing carbohydrate cross-reactive determinant (CCD) did not induce a reduction in Dpt IgE. The Dpt IgG4 were not significantly different. Conclusion Helminth infections induced IgE against allergens such as Dpt and molecular components that belong to different sources as well as against CCD (such as β-1,2-xylose and/or ⍺-1,3-fucose substituted N-glycans). Dpt IgE were not able to induce degranulation of mast cells and were not explained by sensitization to usual major allergens or N-glycans.

Relevance of Major Allergens in Weed Pollen Allergy

<b><i>Introduction:</i></b> Weed pollen allergy is an important and in prevalence increasing cause of pollinosis in Europe and across the world. In this study we focus on the value of common diagnostic tools for detection of a sensitization to mugwort and English plantain, especially with regard to the clinical relevance of the sensitization. <b><i>Methods:</i></b> Eighty weed pollen sensitized patients (41 to mugwort and 39 to English plantain) were assessed retrospectively regarding their clinical anamnesis, in-vivo tests (skin prick test [SPT] and allergen specific provocation) and in-vitro tests (immunoglobulin E [IgE] reactivity to purified natural allergen extract and specific allergen components in serum). <b><i>Results:</i></b> 85% of mugwort and 83% of English plantain sensitizations could be diagnosed by SPT alone. Distinction between allergic and non-allergic patients could be made with clinical challenges solely. IgE serology revealed IgE antibodies against the native pollen extracts for mugwort in 98% and for English plantain in 90% of patients. Detection of major allergens nArt v 1, nArt v 3 and Pla l 1 did not add accuracy to the diagnosis. A vast majority of the weed pollen allergic patients was sensitized to &#x3e;1 allergen. Minor allergens were found to be of less importance. <b><i>Conclusion:</i></b> The exact diagnosis of weed pollen allergy can be challenging due to confounding components in anamnesis and diagnostic tests. IgE-serology does not delineate allergic from sensitized patients. Component resolved diagnostics (CRD) can confirm, but not replace, extract based diagnostic methods, such as SPT, provocation tests or serology to native extracts. Hence, these are the gold standard diagnostic tools in weed pollen allergy up to now.

Identification of Common and Novel Major Crab Allergens in Scylla tranquebarica and the Allergen Stability in Untreated and Vinegar-treated Crab

Crab allergy is reported as a serious form of food allergy in many countries. This study was aimed to identify the major allergens of the local mud crab, Scylla tranquebarica (S. tranquebarica), and subsequently, determine the effect of vinegar treatments on the crab allergens. Crab muscles were treated with synthetic and natural vinegar. Crab proteins were then extracted from the untreated and vinegar-treated crabs. All extracts were then fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and analyzed by immunoblotting; using sera from crab-allergic patients. The crab proteins were then further fractionated by two-dimensional electrophoresis (2-DE) and analyzed by mass spectrometry (MS). The untreated crab had 38 protein bands, while that was only a few bands between 18 to 73 kDa for the vinegar-treated crabs. Immunoblotting of untreated crab revealed 20 IgE-binding bands, whereas the vinegar-treated crabs could only retain a few IgE-binding bands. Five major allergens were identified with molecular weightsof38, 42, 49, 63, and 73 kDa in the untreated crab. In contrast, the vinegar-treated crabs had only a few major allergens with molecular weights of 38, 42, and 73 kDa. MS identified the 43 and 49 kDa as arginine kinase, while the 38, 63, and 73 kDa were identified as tropomyosin, actin, and hemocyanin, respectively. In conclusion, we found three common major allergens for S. tranquebarica including tropomyosin, arginine kinase, and actin, and one novel allergen known as hemocyanin. All the major allergens could retain minimal allergenic capability in vinegar-treated crabs, suggesting that vinegar treatments might be useful to reduce crab allergenicity. These data would assist the clinicians in the management of crab-allergic patients worldwide.