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Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Life Science / Faculty of Advanced Life Science >
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Recognition of CpG oligodeoxynucleotides by human Toll-like receptor 9 and subsequent cytokine induction
| Title: | Recognition of CpG oligodeoxynucleotides by human Toll-like receptor 9 and subsequent cytokine induction |
| Authors: | Suwarti, Suwarti Browse this author | | Yamazaki, Tomohiko Browse this author | | Svetlana, Chechetka Browse this author | | Hanagata, Nobutaka Browse this author →KAKEN DB |
| Keywords: | Toll-like receptor 9 | | Oligodeoxynucleotide | | Immunostimulatory | | Ligand-binding sites | | Extracellular domain |
| Issue Date: | 25-Jan-2013 |
| Publisher: | Elsevier |
| Journal Title: | Biochemical and Biophysical Research Communications |
| Volume: | 430 |
| Issue: | 4 |
| Start Page: | 1234 |
| End Page: | 1239 |
| Publisher DOI: | 10.1016/j.bbrc.2012.12.068 |
| PMID: | 23266611 |
| Abstract: | Toll-like receptor 9 (TLR9) recognizes a synthetic ligand, oligodeoxynucleotide (ODN) containing cytosine-phosphate-guanine (CpG). Induction of TLR9 by CpG ODN activates a signal transduction cascade that plays a pivotal role in first-line immune defense in the human body. The three-dimensional structure of TLR9 has not yet been reported, and the ligand-binding mechanism of TLR9 is still poorly understood; therefore, the mechanism of human TLR9 ligand binding needs to be elucidated. In functional studies of TLR9, phosphorothioate (PTO)-modified CpG ODNs have been utilized because "natural" CpG ODNs consist entirely of a phosphodiester (PD) backbone that is easily degraded by nucleases. However, PTO ODNs do not faithfully recapitulate natural DNA-mediated TLR9 activation. In this study, we constructed several human TLR9 mutants, including predicted truncated mutants and single mutants in the predicted CpG ODN-binding site. We used these mutants to analyze the role of potential important regions of TLR9 in receptor signaling induced by stable PD-ODNs that we developed. We clarified that both the C- and N-termini of the extracellular domain (ECD) are necessary for the function of TLR9 in human cells, even if only the C-terminal region of mouse TLR9-ECD was activated by CpG ODNs. Next, we identified residues in the C-terminus of TLR9-ECD (H505 in leucine-rich repeat (LRR)-16, H530 in LRR-17, and Y554 in LRR-18) that are essential for hTLR9 activation. Furthermore, we utilized PD-ODN to analyze the function of TLR9 in peripheral blood mononuclear cells and B cells. PD-ODNs showed perfect sequence-dependent TLR9 activation, whereas both CpG and non-CpG PTO-ODN activated TLR9. Hence, our study revealed the specific use of natural PD-ODN to explore the function of TLR9, which is required for its development as a potential therapeutic adjuvant. |
| Type: | article (author version) |
| URI: | http://hdl.handle.net/2115/52237 |
| Appears in Collections: | 生命科学院・先端生命科学研究院 (Graduate School of Life Science / Faculty of Advanced Life Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 花方 信孝
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