CpG oligodeoxynucleotide-specific goose TLR21 initiates an anti-viral immune response against NGVEV but not AIV strain H9N2 infection.

Abstract

Toll-like receptors (TLRs) recognize components of pathogens and mediate the host innate immune response. TLR21 is a TLR that specifically recognizes exogenous double-stranded DNA and rapidly signals to downstream innate immune factors. This study reports the cDNA of goose TLR21 and identifies its immune characteristics. The goose TLR21 is 3161 base pairs and encodes a 975 amino acid protein. As predicted, the goose transmembrane protein TLR21 has a signal peptide, leucine-rich repeat regions, a transmembrane domain, and a Toll/interleukin-1 receptor domain. Multiple sequence alignments and phylogenetic analyses showed that goose TLR21 has homology to chicken TLR21. The tissue distribution of TLR21 suggested that it has high transcript levels in immune-associated tissues, especially in the bursa of Fabricius, the Hadrian gland, and the thymus. After challenge with agonist ODN2006 and new type gosling viral enteritis virus (NGVEV), significant induction of TLR21 production, pro-inflammatory cytokines IL-1β and IL-6, and interferons were observed in peripheral blood mononuclear cells. Both synthetic DNA (ODN2006) and viral DNA (NGVEV) can be recognized by goose TLR21, which leads to a rapid up-regulation of pro-inflammatory cytokines and anti-viral molecules. In vivo, avian influenza A virus H9N2 and NGVEV were used to infect goslings, which was followed by a significant up-regulation of TLR21 mRNA transcripts in multiple tissues of NGVEV-infected geese. In general, goose TLR21 plays an important role in binding invading pathogenic DNA viruses, which subsequently triggers an innate immune response; furthermore, it acts as a functional homologue of mammalian TLR9, as TLR21 recognizes a mammalian TLR9 agonist.

• Authors: Yulin Qi, Bing Yan, Shun Chen, Hongjun Chen, Mingshu Wang, Renyong Jia, Dekang Zhu, Mafeng Liu, Fei Liu, Qiao Yang, Kunfeng Sun, Ying Wu, Xiaoyue Chen, Bo Jing, Anchun Cheng
• Journal: Immunobiology (Immunobiology) Vol. 221 Issue 3 Pg. 454-61 (Mar 2016) ISSN: 1878-3279 [Electronic] Netherlands
• PMID: 26621545 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 Elsevier GmbH. All rights reserved.

Chemical References

• CPG-oligonucleotide
• Cytokines
• Inflammation Mediators
• Oligodeoxyribonucleotides
• Toll-Like Receptors

Topics

• Amino Acid Sequence
• Animals
• Cloning, Molecular
• Cytokines (metabolism)
• Geese
• Inflammation Mediators
• Influenza A Virus, H9N2 Subtype (classification, immunology)
• Influenza in Birds (genetics, immunology, metabolism, virology)
• Leukocytes, Mononuclear (immunology, metabolism)
• Models, Molecular
• Molecular Sequence Data
• Oligodeoxyribonucleotides (immunology)
• Phylogeny
• Protein Conformation
• Protein Transport
• Sequence Alignment
• Sequence Analysis, DNA
• Toll-Like Receptors (chemistry, genetics, metabolism)