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Polylactosamine on glycoproteins influences basal levels of lymphocyte and macrophage activation.

ABSTRACT: beta1,3-N-acetylglucosaminyltransferase 2 (beta3GnT2) is a polylactosamine synthase that synthesizes a backbone structure of carbohydrate structures onto glycoproteins. Here we generated beta3GnT2-deficient (beta3GnT2(-/-)) mice and showed that polylactosamine on N-glycans was markedly reduced in their immunological tissues. In WT mice, polylactosamine was present on CD28 and CD19, both known immune costimulatory molecules. However, polylactosamine levels on these molecules were reduced in beta3GnT2(-/-) mice. beta3GnT2(-/-) T cells lacking polylactosamine were more sensitive to the induction of intracellular calcium flux on stimulation with anti-CD3epsilon/CD28 and proliferated more strongly than T cells from WT mice. beta3GnT2(-/-) B cells also showed hyperproliferation on BCR stimulation. Macrophages from beta3GnT2(-/-) mice had higher cell surface CD14 levels and enhanced responses to endotoxin. These results indicate that polylactosamine on N-glycans is a putative immune regulatory factor presumably suppressing excessive responses during immune reactions.

SUBMITTER: Togayachi A

PROVIDER: S-EPMC2000437 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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Polylactosamine on glycoproteins influences basal levels of lymphocyte and macrophage activation.

Togayachi Akira A Kozono Yuko Y Ishida Hiroyasu H Abe Sumie S Suzuki Nami N Tsunoda Yuki Y Hagiwara Kozue K Kuno Atsushi A Ohkura Takashi T Sato Nobuo N Sato Takashi T Hirabayashi Jun J Ikehara Yuzuru Y Tachibana Kouichi K Narimatsu Hisashi H

Proceedings of the National Academy of Sciences of the United States of America 20070921 40

beta1,3-N-acetylglucosaminyltransferase 2 (beta3GnT2) is a polylactosamine synthase that synthesizes a backbone structure of carbohydrate structures onto glycoproteins. Here we generated beta3GnT2-deficient (beta3GnT2(-/-)) mice and showed that polylactosamine on N-glycans was markedly reduced in their immunological tissues. In WT mice, polylactosamine was present on CD28 and CD19, both known immune costimulatory molecules. However, polylactosamine levels on these molecules were reduced in beta3 ...[more]

PMID: 17890318

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Polylactosamine on glycoproteins influences basal levels of lymphocyte and macrophage activation.

Publications

Polylactosamine on glycoproteins influences basal levels of lymphocyte and macrophage activation.

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