Identification of the critical amino acid residues of immunoglobulin E and immunoglobulin G epitopes on αs1-casein by alanine scanning analysis.

Abstract

αs1-Casein represents one of the major allergens causing cow milk allergy. Few studies have clearly evaluated immunological relationships between IgE- and IgG-binding epitopes of αs1-casein. This study aimed to map IgE- and IgG-binding epitopes of αs1-casein by the serology method, and identify the critical amino acids of αs1-casein by alanine scanning analysis. Our initial data revealed IgE-binding epitopes located in the sequences of AA 126 to 140, AA 6 to 20, AA 171 to 185, and AA 11 to 25. The sequences at AA 21 to 35, AA 56 to 70, and AA 161 to 175 were recognized by IgG antibodies. The alanine scanning analysis showed that IgE- and IgG-binding epitopes share the same critical AA: arginine at position 22 and phenylalanine at position 23. Results obtained from this study will provide necessary information to alter the cDNA to encode a protein with reduced IgE- or IgG-binding capacity.

• Authors: Yanjun Cong, Hong Yi, Yuting Qing, Linfeng Li
• Journal: Journal of dairy science (J Dairy Sci) Vol. 96 Issue 11 Pg. 6870-6876 ( 2013) ISSN: 1525-3198 [Electronic] United States
• PMID: 24035023 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Chemical References

• Allergens
• Caseins
• Epitopes
• Immunoglobulin G
• Immunoglobulin E
• Alanine

Topics

• Alanine (analysis)
• Allergens (immunology)
• Animals
• Caseins (chemistry)
• Cattle
• Epitopes (chemistry, immunology)
• Female
• Immunoglobulin E (chemistry, metabolism)
• Immunoglobulin G (chemistry)
• Milk Hypersensitivity (immunology)
• Protein Binding