Comparison of 2D proteomic maps revealed properties of Ambrosia artemisiifolia sub-pollen particles accounting for more severe asthma symptoms than its whole pollen grains

Aims and scopes: It is known that sub-pollen particles (SPP) cause more severe symptoms of asthma than its whole pollen grain counterparts, due to its smaller size and ability to penetrate deeper into the lungs. To reveal other possible causes of such more severe asthma symptoms induced by Ambrosia artemisiifolia SPP, its sub-pollen particle and pollen grain proteomes were characterized and compared. Experimental description: Protein extract of short ragweed (Ambrosia artemisiifolia) pollen and its SPP were prepared and subjected to denaturing 2-D electrophoresis. Pollen proteome spots were excised a er colloidal coomassie blue brillinat (cCBB) staining and in gel digested for liquid chromatography coupled with high resolution LTQ Orbitrap XL hybrid mass spectrometry. Parallel to that, cCBB stained gels were analyzed and quanti ed with laser scanner Typhoon 7000 series and Image 2D Master Platinum 7.0 soware (GE Healthcare, USA). Results: ere is statistically signi cant di erence between the contents of major allergen Amb a 1.05 subgroup in the ragweed whole pollen grains and SPP, the latter being richer in Amb a 1.05 (2 times), in major allergen Amb a 11 (5 times), in minor allergens Amb a 4 (7 times) and Amb a 6 (4 times). e 30 kDa basic antigen group in SPP (8 times more abundant) needs further investigation. sia artemisiifolia allergens, Amb a 1.05 and Amb a 11, minor allergens Amb a 4 and Amb a 6 which could contribute to more severe asthma symptoms caused by SPP

The α-Gal epitope - the cause of a global allergic disease

The galactose-α-1,3-galactose (α-Gal) epitope is the cause of a global allergic disease, the α-Gal syndrome (AGS). It is a severe form of allergy to food and products of mammalian origin where IgE against the mammalian carbohydrate, α-Gal, is the cause of the allergic reactions. Allergic reactions triggered by parenterally administered α-Gal sources appear immediately, but those triggered via the oral route appear with a latency of several hours. The α-Gal epitope is highly immunogenic to humans, apes and old-world monkeys, all of which produce anti-α-Gal antibodies of the IgM, IgA and IgG subclasses. Strong evidence suggests that in susceptible individuals, class switch to IgE occurs after several tick bites. In this review, we discuss the strong immunogenic role of the α-Gal epitope and its structural resemblance to the blood type B antigen. We emphasize the broad abundance of α-Gal in different foods and pharmaceuticals and the allergenicity of various α-Gal containing molecules. We give an overview of the association of tick bites with the development of AGS and describe innate and adaptive immune response to tick saliva that possibly leads to sensitization to α-Gal. We further discuss a currently favored hypothesis explaining the mechanisms of the delayed effector phase of the allergic reaction to α-Gal. We highlight AGS from a clinical point of view. We review the different clinical manifestations of the disease and the prevalence of sensitization to α-Gal and AGS. The usefulness of various diagnostic tests is discussed. Finally, we provide different aspects of the management of AGS. With climate change and global warming, the tick density is increasing, and their geographic range is expanding. Thus, more people will be affected by AGS which requires more knowledge of the disease

Antioxidative capacity and binding affinity of the complex of green tea catechin and beta-lactoglobulin glycated by the Maillard reaction

Major green tea catechin, epigallocatechin-3-gallate (EGCG), binds non-covalently to numerous dietary proteins, including beta-lactoglobulin of cow's milk. The effects of glycation of proteins via Maillard reaction on the binding capacity for polyphenols and the antiradical properties of the formed complexes have not been studied previously. Binding constant of BLG glycated by milk sugar lactose to EGCG was measured by the method of fluorophore quenching. Binding of EGCG was confirmed by CD and FTIR. The antioxidative properties of the complexes were examined by measuring ABTS radical scavenging capacity, superoxide anion scavenging capacity and total reducing power assay. Glycation of BLG does not significantly influence the binding constant of EGCG for the protein. Conformational changes were observed for both native and glycated BLG upon complexation with EGCG. Masking effect of polyphenol complexation on the antioxidative potential of the protein was of the similar degree for both glycated BLG and native BLG

Glycation of the Major Milk Allergen β-Lactoglobulin Changes its Allergenicity by Alterations in Cellular Uptake and Degradation

SCOPE: During food processing the Maillard reaction (МR) may occur resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergy since glycation may influence interactions with immune system. This study compared native and extensively glycated milk allergen β-lactoglobulin (BLG), in their interactions with cells crucially involved in allergy. METHODS AND RESULTS: BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T-cell cytokine responses and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco-2 monolayer. Uptake of glycated BLG by bone marrow-derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor-mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4+ T-cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG-specific IgE sensitized basophil cells. CONCLUSIONS: This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy. This article is protected by copyright. All rights reserved

Glycation of the Major Milk Allergen β-Lactoglobulin Changes its Allergenicity by Alterations in Cellular Uptake and Degradation

SCOPE: During food processing the Maillard reaction (МR) may occur resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergy since glycation may influence interactions with immune system. This study compared native and extensively glycated milk allergen β-lactoglobulin (BLG), in their interactions with cells crucially involved in allergy. METHODS AND RESULTS: BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T-cell cytokine responses and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco-2 monolayer. Uptake of glycated BLG by bone marrow-derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor-mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4+ T-cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG-specific IgE sensitized basophil cells. CONCLUSIONS: This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy. This article is protected by copyright. All rights reserved