TY - JOUR

T1 - Glycoproteomic analysis of seven major allergenic proteins reveals novel post-translational modifications

AU - Halim, Adnan

AU - Carlsson, Michael C

AU - Mathiesen, Caroline Benedicte K

AU - Brand, Stephanie

AU - Möller, Svenning Rune

AU - Olsen, Carl Erik

AU - Vakhrushev, Sergey Y

AU - Brimnes, Jens

AU - Wurtzen, Peter Adler

AU - Ipsen, Henrik

AU - Petersen, Bent L

AU - Wandall, Hans H

N1 - © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

PY - 2015

Y1 - 2015

N2 - Allergenic proteins such as grass pollen and house dust mite (HDM) proteins are known to trigger hypersensitivity reactions of the immune system, leading to what is commonly known as allergy. Key allergenic proteins including sequence variants have been identified but characterization of their post-translational modifications (PTMs) is still limited. Here, we present a detailed PTM(1) characterization of a series of the main and clinically relevant allergens used in allergy tests and vaccines. We employ Orbitrap-based mass spectrometry with complementary fragmentation techniques (HCD/ETD) for site-specific PTM characterization by bottom-up analysis. In addition, top-down mass spectrometry is utilized for targeted analysis of individual proteins, revealing hitherto unknown PTMs of HDM allergens. We demonstrate the presence of lysine-linked polyhexose glycans and asparagine-linked N-acetylhexosamine glycans on HDM allergens. Moreover, we identified more complex glycan structures than previously reported on the major grass pollen group 1 and 5 allergens, implicating important roles for carbohydrates in allergen recognition and response by the immune system. The new findings are important for understanding basic disease-causing mechanisms at the cellular level, which ultimately may pave the way for instigating novel approaches for targeted desensitization strategies and improved allergy vaccines.

AB - Allergenic proteins such as grass pollen and house dust mite (HDM) proteins are known to trigger hypersensitivity reactions of the immune system, leading to what is commonly known as allergy. Key allergenic proteins including sequence variants have been identified but characterization of their post-translational modifications (PTMs) is still limited. Here, we present a detailed PTM(1) characterization of a series of the main and clinically relevant allergens used in allergy tests and vaccines. We employ Orbitrap-based mass spectrometry with complementary fragmentation techniques (HCD/ETD) for site-specific PTM characterization by bottom-up analysis. In addition, top-down mass spectrometry is utilized for targeted analysis of individual proteins, revealing hitherto unknown PTMs of HDM allergens. We demonstrate the presence of lysine-linked polyhexose glycans and asparagine-linked N-acetylhexosamine glycans on HDM allergens. Moreover, we identified more complex glycan structures than previously reported on the major grass pollen group 1 and 5 allergens, implicating important roles for carbohydrates in allergen recognition and response by the immune system. The new findings are important for understanding basic disease-causing mechanisms at the cellular level, which ultimately may pave the way for instigating novel approaches for targeted desensitization strategies and improved allergy vaccines.

U2 - 10.1074/mcp.M114.042614

DO - 10.1074/mcp.M114.042614

M3 - Journal article

C2 - 25389185

VL - 14

SP - 191

EP - 204

JO - Molecular and Cellular Proteomics

JF - Molecular and Cellular Proteomics

SN - 1535-9476

IS - 1

ER -