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PIPE-cloned human IgE and IgG4 antibodies: New tools for investigating cow's milk allergy and tolerance Abbreviations AIT allergen immunotherapy BAT basophil activation test BLG beta-lactoglobulin CM cow's milk CMA cow's milk allergy D1 name of engineered antibodies due to their published, variable regions ELISA enzyme-linked immunosorbent assay FA-AIT food allergen immunotherapy IL interleukin ISAC Immuno-Solid phase Allergy Chip OIT oral immunotherapy PBMC peripheral blood mononuclear cells PIPE cloning polymerase incomplete primer extension cloning RT room temperature SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis TBS Tris-buffered saline TBS-T TBS-Tween UHT milk ultra-high temperature processed milk Cow's milk (CM) allergy (CMA) is defined as an immune-mediated adverse response to CM proteins. Allergic children had significantly higher levels of IgE ( I P i < .01), but no differences in the IgG4 levels were seen between the groups (Figure S2), in accordance with previous studies.8 Our data suggest that the PIPE-cloned antibodies may be useful for a precise quantification of allergen-specific IgE and IgG4. [Extracted from the article]

The lipocalin beta-lactoglobulin (BLG) is a major protein compound in cow's milk, and we detected it in cattle stable dust. BLG may be a novel player in the farm protective effect against atopic sensitization and hayfever. In previous studies, we demonstrated that only the ligand-filled holo-form of BLG prevented sensitization to itself. Here, we investigated whether holo-BLG could, in an innate manner, also protect against allergic sensitization to unrelated birch pollen allergens using a murine model. BALB/c mice were nasally pretreated four times in biweekly intervals with holo-BLG containing quercetin–iron complexes as ligands, with empty apo-BLG, or were sham-treated. Subsequently, mice were intraperitoneally sensitized two times with apo-BLG or with the unrelated birch pollen allergen apo-Bet v 1, adjuvanted with aluminum hydroxide. After subsequent systemic challenge with BLG or Bet v 1, body temperature drop was monitored by anaphylaxis imaging. Specific antibodies in serum and cytokines of BLG- and Bet v 1-stimulated splenocytes were analyzed by ELISA. Additionally, human peripheral blood mononuclear cells of pollen allergic subjects were stimulated with apo- versus holo-BLG before assessment by FACS. Prophylactic treatment with the holo-BLG resulted in protection against allergic sensitization and clinical reactivity also to Bet v 1 in an unspecific manner. Pretreatment with holo-BLG resulted in significantly lower BLG-as well as Bet v 1-specific antibodies and impaired antigen-presentation with significantly lower numbers of CD11c+MHCII+ cells expressing CD86. Pretreatment with holo-BLG also reduced the release of Th2-associated cytokines from Splenocytes in BLG-sensitized mice. Similarly, in vitro stimulation of PBMCs from birch pollen allergic subjects with holo-BLG resulted in a relative decrease of CD3+CD4+ and CD4+CRTh2 cells, but not of CD4+CD25+CD127− Treg cells, compared to apo-BLG stimulation. In conclusion, prophylactic treatment with holo-BLG protected against allergy in an antigen-specific and -unspecific manner by decreasing antigen presentation, specific antibody production and abrogating a Th2-response. Holo-BLG therefore promotes immune resilience against pollen allergens in an innate manner and may thereby contribute to the farm protective effect against atopic sensitization. [ABSTRACT FROM AUTHOR]

Retinoic acid-loading of the major birch pollen allergen Bet v 1 may improve specific allergen immunotherapy: In silico, in vitro and in vivo data in BALB/c mice Even if this was not due to altered endolysosomal stability of Bet v 1a due to RA binding (Figure S3), it seemed so far like RA-loading transforms the hyperallergen Bet v 1a to a hypoallergen with improved tolerogenic capacity of potential implications for allergen immunotherapy. Mice were first made allergic against the major birch pollen allergen Bet v 1a and subsequently treated intranasally with either the I apo i -Bet v 1a, or with the RA-loaded I holo i -Bet v 1a, or as a control with RA alone. [Extracted from the article]

Worldwide 300 million children and adults are affected by asthma. The development of asthma is influenced by environmental and other exogenous factors synergizing with genetic predisposition, and shaping the lung microbiome especially during birth and in very early life. The healthy lung microbial composition is characterized by a prevalence of bacteria belonging to the phyla Bacteroidetes, Actinobacteria, and Firmicutes. However, viral respiratory infections are associated with an abundance of Proteobacteria with genera Haemophilus and Moraxella in young children and adult asthmatics. This dysbiosis supports the activation of inflammatory pathways and contributes to bronchoconstriction and bronchial hyperresponsiveness. Exogenous factors can affect the natural lung microbiota composition positively (farming environment) or negatively (allergens, air pollutants). It is evident that also gut microbiota dysbiosis has a high influence on asthma pathogenesis. Antibiotics, antiulcer medications, and other drugs severely impair gut as well as lung microbiota. Resulting dysbiosis and reduced microbial diversity dysregulate the bidirectional crosstalk across the gut-lung axis, resulting in hypersensitivity and hyperreactivity to respiratory and food allergens. Efforts are undertaken to reconstitute the microbiota and immune balance by probiotics and engineered bacteria, but results from human studies do not yet support their efficacy in asthma prevention or treatment. Overall, dysbiosis of gut and lung seem to be critical causes of the increased emergence of asthma. [ABSTRACT FROM AUTHOR]

For proteins to become allergenic, they need to acquire features enabling them to induce B cell activation and isotype switch to IgE production. Crosslinking of the B-cell receptor (BCR) is the most efficient way to productively activate B-cells. The IgE-crosslinking capability of allergens is equally crucial in the effector phase of immediate type allergy. Antigens, which acquire enhanced crosslinking capacity by oligomerization, aggregation, or the expression of repetitive epitopes may therefore gain allergenic potency. The accumulated evidence for repetitive epitope display by allergens suggests the existence of allergen-associated molecular patterns. [ABSTRACT FROM AUTHOR]