Identification of Seasonal Variations of Antibodies against PR-10-Specific Epitopes Can Be Improved Using Peptide-Phage Display

Background: In pollinosis patients, allergen-specific antibody titers show seasonal variations. Little is known about these variations at the epitope level. Objectives: We aimed at investigating seasonal variations on the level of allergen epitope recognition in patients with Bet v 1-related food allergy using a peptide phage display approach. Methods: Serum samples collected over 1 year from 4 patients of the placebo arm of the birch-associated soya allergy immunotherapy trial were included. To identify epitopes from Bet v 1-related food allergens, patient sera were used in peptide phage display experiments. In silico analysis of enriched allergen-related motifs was performed. Results: We identified epitope motifs related to Bet v 1 and its homologs in soya and hazelnut (Gly m 4 and Cor a 1, respectively) that were enriched in accordance with birch and hazel pollen exposure. Within several weeks after the birch pollen season peak, the pattern of identified epitope motifs differed considerably among patients. Data for amino acid preferences in homologous Bet v 1 and Cor a 1 epitope motifs identified for one of the investigated patients suggest changes in concentration or specificity of serum antibodies for the Cor a 1 epitope motif. Conclusions: Peptide phage display data suggest an impact of birch and hazel pollen exposure on the recognition pattern of Bet v 1-like allergen epitopes. Epitope-oriented analyses could provide deeper, personalized details regarding the allergen epitope recognition influenced by pollen exposure beyond the capability of current methods.

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Antibody response after hepatitis B vaccine boost mapped with peptide-phage display

Bionatura ◽

10.21931/rb/cs/2019.02.01.2 ◽

2019 ◽

Vol 02 (Bionatura Conference Serie) ◽

Author(s):

Lisbeth Ramírez Caballero ◽

Nicolas Delaroque ◽

Michael Szardenings

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Phage Display ◽

In Silico ◽

Hepatitis B Surface Antigen ◽

In Silico Analysis ◽

Hepatitis B Vaccination ◽

Serum Samples ◽

B Virus ◽

Peptide Phage Display

Recombinant hepatitis B virus vaccines confer protection by eliciting specific antibodies against the hepatitis B surface antigen (HBsAg), known as anti-HBs. However, the performance of rapid anti-HBs diagnostic tests generates concerns regarding consistency. Novel indicators of protection might be developed by monitoring changes in targeted HBsAg-epitope profile after vaccination. In this work, we test the feasibility of our peptide-phage display platform in identifying B-cell epitopes targeted at different time-points after hepatitis B vaccination. We combined this platform with a unique approach for in silico analysis of enriched sequences. Serum samples collected from one single patient who had two boosting immunizations against hepatitis B virus were used in two-rounds of selection experiments. Five epitope candidates from HBsAg were identified in silico; most of them were previously reported in the literature. Our results suggest that the number of recognized HBsAg epitopes is related to the decrease of anti-HBs over time.

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Preparation and properties evaluation of the recombinant analogue of birch pollen allergen Bet v 1

Rossiiskii Allergologicheskii ZHurnal ◽

10.36691/rja678 ◽

2012 ◽

Vol 9 (3) ◽

pp. 7-13

Author(s):

A E Pavlov ◽

N A Seylieva ◽

O YU Mukhortykh ◽

V E Stefanov

Keyword(s):

Immunoglobulin E ◽

Birch Pollen ◽

High Yield ◽

Synthetic Analogue ◽

Serum Samples ◽

E Coli ◽

Bet V 1 ◽

Allergenic Component ◽

Birch Pollen Allergen ◽

Allergy Diagnostics

Background. For wide introduction of the component allergy diagnostics in laboratory practice it is necessary to create methods of production, purification and verification of synthetic allergens. Major birch pollen protein Bet v 1, a representative of the superfamily PR-10, is interesting due to the high incidence of sensitization and the manifestation of cross-reactive properties. Methods. To receive a synthetic protein DNA cloning techniques were used, followed by expression in E. coli. Purification was made by metal-affinity chromatography. Evaluation of immunochemical properties was held in several tests including ELISA analysis and line-blot. Results. We have obtained high-yield bacterial strain E. coli, containing expression vector for protein Bet v 1 production. Physico-chemical and immunological properties were estimated in various test systems with the reference panel of serum. Conclusion. It was shown that the resulting synthetic analogue of protein Bet v 1 can be used to measure the presence of specific immunoglobulin E in serum samples. This allergenic component may be used for estimation of each component of the sensitization profile.

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Depigmented Allergoids Reveal New Epitopes with Capacity to Induce IgG Blocking Antibodies

BioMed Research International ◽

10.1155/2013/284615 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

M. Angeles López-Matas ◽

Mayte Gallego ◽

Víctor Iraola ◽

Douglas Robinson ◽

Jerónimo Carnés

Keyword(s):

Birch Pollen ◽

Igg Antibodies ◽

Serum Samples ◽

Bet V 1 ◽

Ige Binding ◽

Linear Epitopes ◽

Specific Igg ◽

Allergen Extracts ◽

Blocking Antibodies ◽

Specific Igg Antibodies

Background. The synthesis of allergen-specific blocking IgGs that interact with IgE after allergen immunotherapy (SIT) has been related to clinical efficacy. The objectives were to investigate the epitope specificity of IgG-antibodies induced by depigmented-polymerized (Dpg-Pol) allergoids and unmodified allergen extracts, and examine IgE-blocking activity of induced IgG-antibodies.Methods. Rabbits were immunized with native and Dpg-Pol extracts of birch pollen, and serum samples were obtained. Recognition of linear IgG-epitopes of Bet v 1 and Bet v 2 and the capacity of these IgG-antibodies to block binding of human-IgE was determined.Results. Serum from rabbits immunized with native extracts recognised 11 linear epitopes from Bet v 1, while that from Dpg-Pol-immunized animals recognised 8. For Bet v 2, 8 epitopes were recognized by IgG from native immunized animals, and 9 from Dpg-Pol immunized one. Dpg-Pol and native immunized serum did not always recognise the same epitopes, but specific-IgG from both could block human-IgE binding sites for native extract.Conclusions. Depigmented-polymerized birch extract stimulates the synthesis of specific IgG-antibodies which recognize common but also novel epitopes compared with native extracts. IgG-antibodies induced by Dpg-Pol effectively inhibit human-IgE binding to allergens which may be part of the mechanism of action of SIT.

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