Dataset Information

Limited Lactosylation of Beta-Lactoglobulin from Cow's Milk Exerts Strong Influence on Antigenicity and Degranulation of Mast Cells.

ABSTRACT: beta-lactoglobulin (BLG) is one of the major cow's milk proteins and the most abundant allergen in whey. Heating is a common technologic treatment applied during milk transformational processes. Maillardation of BLG in the presence of reducing sugars and elevated temperatures may influence its antigenicity and allergenicity. to analyze and identify lactosylation sites by capillary electrophoresis mass spectrometry (CE-MS). to assess the effect of lactosylated BLG on antigenicity and degranulation of mast cells. BLG was lactosylated at pH 7, a water activity (aw) of 0.43, and a temperature of 65 °C using a molar ratio BLG:lactose of 1:1 by incubating for 0, 3, 8, 16 or 24 h. For the determination of the effect on antibody-binding capacity of lactosylated BLG, an ELISA was performed. For the assessment of degranulation of the cell-line RBL-hεIa-2B12 transfected with the human α-chain, Fcε receptor type 1 (FcεRI) was used. BLG showed saturated lactosylation between 8 and 16 incubation hours in our experimental setup. Initial stage lactosylation sites L1 (N-terminus)-K47, K60, K75, K77, K91, K138 and K141-have been identified using CE-MS. Lactosylated BLG showed a significant reduction of both the IgG binding (p = 0.0001) as well as degranulation of anti-BLG IgE-sensitized RBL-hεIa-2B12 cells (p < 0.0001). this study shows that lactosylation of BLG decreases both the antigenicity and degranulation of mast cells and can therefore be a promising approach for reducing allergenicity of cow's milk allergens provided that the process is well-controlled.

SUBMITTER: Bosman GP

PROVIDER: S-EPMC8232271 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Limited Lactosylation of Beta-Lactoglobulin from Cow's Milk Exerts Strong Influence on Antigenicity and Degranulation of Mast Cells.

Bosman Gerlof P GP Oliveira Sergio S Simons Peter J PJ Sastre Torano Javier J Somsen Govert W GW Knippels Leon M J LMJ Haselberg Rob R Pieters Roland J RJ Garssen Johan J Knipping Karen K

Nutrients 20210615 6

<h4>Background</h4>beta-lactoglobulin (BLG) is one of the major cow's milk proteins and the most abundant allergen in whey. Heating is a common technologic treatment applied during milk transformational processes. Maillardation of BLG in the presence of reducing sugars and elevated temperatures may influence its antigenicity and allergenicity.<h4>Primary objective</h4>to analyze and identify lactosylation sites by capillary electrophoresis mass spectrometry (CE-MS).<h4>Secondary objective</h4>to ...[more]

PMID: 34203636

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Dataset Information

Limited Lactosylation of Beta-Lactoglobulin from Cow's Milk Exerts Strong Influence on Antigenicity and Degranulation of Mast Cells.

Publications

Limited Lactosylation of Beta-Lactoglobulin from Cow's Milk Exerts Strong Influence on Antigenicity and Degranulation of Mast Cells.

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