Glycan analysis of human neutrophil granules implicates a maturation-dependent glycosylation machinery
Journal article, 2020

Protein glycosylation is essential to trafficking and immune functions of human neutrophils. During granulopoiesis in the bone marrow, distinct neutrophil granules are successively formed. Distinct receptors and effector proteins, many of which are glycosylated, are targeted to each type of granule according to their time of expression, a process called "targeting by timing." Therefore, these granules are time capsules reflecting different times of maturation that can be used to understand the glycosylation process during granulopoiesis. Herein, neutrophil subcellular granules were fractionated by Percoll density gradient centrifugation, andN- andO-glycans present in each compartment were analyzed by LC-MS. We found abundant paucimannosidicN-glycans and lack ofO-glycans in the early-formed azurophil granules, whereas the later-formed specific and gelatinase granules and secretory vesicles contained complexN-andO-glycans with remarkably elongatedN-acetyllactosamine repeats with Lewis epitopes. Immunoblotting and histochemical analysis confirmed the expression of Lewis X and sialyl-Lewis X in the intracellular granules and on the cell surface, respectively. Many glycans identified are unique to neutrophils, and their complexity increased progressively from azurophil granules to specific granules and then to gelatinase granules, suggesting temporal changes in the glycosylation machinery indicative of "glycosylation by timing" during granulopoiesis. In summary, this comprehensive neutrophil granule glycome map, the first of its kind, highlights novel granule-specific glycosylation features and is a crucial first step toward a better understanding of the mechanisms regulating protein glycosylation during neutrophil granulopoiesis and a more detailed understanding of neutrophil biology and function.

O-glycan

liquid chromatography

N-linked glycosylation

targeting by timing

plasma membrane

N-glycan

LacNAc

neutrophil

glycosylation

Lewis epitope

mass spectrometry (MS)

neutrophil

granule

Author

Vignesh Venkatakrishnan

University of Gothenburg

Regis Dieckmann

University of Gothenburg

Ian Loke

Cordlife Group

Macquarie University

Harry C. Tjondro

Macquarie University

Sayantani Chatterjee

Macquarie University

Johan Bylund

University of Gothenburg

Morten Thaysen-Andersen

Macquarie University

Niclas G. Karlsson

University of Gothenburg

Anna Karlsson-Bengtsson

Chalmers, Biology and Biological Engineering, Chemical Biology

University of Gothenburg

Journal of Biological Chemistry

0021-9258 (ISSN) 1083-351X (eISSN)

Vol. 295 36 12648-12660

Subject Categories

Biochemistry and Molecular Biology

Other Basic Medicine

Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)

DOI

10.1074/jbc.RA120.014011

PubMed

32665399

More information

Latest update

2/23/2021