Dataset Information

PGLYRP-2 and Nod2 are both required for peptidoglycan-induced arthritis and local inflammation.

ABSTRACT: Peptidoglycan recognition proteins (PGRPs) are structurally conserved from insects to mammals. Insect PGRPs have diverse host-defense functions. Mammalian PGRPs PGLYRP-1, PGLYRP-3, and PGLYRP-4 have bactericidal activity, while PGLYRP-2 has amidase activity. To extend the known functions of mammalian PGRPs, we examined whether they have immunomodulating activities in peptidoglycan-induced arthritis in mice. We demonstrate that PGLYRP-2 and Nod2 are both required for arthritis in this model. The sequence of events in peptidoglycan-induced arthritis is activation of Nod2, local expression of PGLYRP-2, chemokine production, and recruitment of neutrophils into the limbs, which induces acute arthritis. Only PGLYRP-2 among the four mammalian PGRPs displays this proinflammatory function, and PGLYRP-1 is anti-inflammatory. Toll-like receptor 4 (TLR4) and MyD88 are required for maturation of neutrophils before peptidoglycan challenge. Our results demonstrate that PGRPs, Nod2, and TLR4, representing three different types of pattern-recognition molecules, play interdependent in vivo roles in local inflammation.

SUBMITTER: Saha S

PROVIDER: S-EPMC2671207 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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PGLYRP-2 and Nod2 are both required for peptidoglycan-induced arthritis and local inflammation.

Saha Sukumar S Qi Jin J Wang Shiyong S Wang Minhui M Li Xinna X Kim Yun-Gi YG Núñez Gabriel G Gupta Dipika D Dziarski Roman R

Cell host & microbe 20090201 2

Peptidoglycan recognition proteins (PGRPs) are structurally conserved from insects to mammals. Insect PGRPs have diverse host-defense functions. Mammalian PGRPs PGLYRP-1, PGLYRP-3, and PGLYRP-4 have bactericidal activity, while PGLYRP-2 has amidase activity. To extend the known functions of mammalian PGRPs, we examined whether they have immunomodulating activities in peptidoglycan-induced arthritis in mice. We demonstrate that PGLYRP-2 and Nod2 are both required for arthritis in this model. The ...[more]

PMID: 19218085

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PGLYRP-2 and Nod2 are both required for peptidoglycan-induced arthritis and local inflammation.

Publications

PGLYRP-2 and Nod2 are both required for peptidoglycan-induced arthritis and local inflammation.

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