Project/Area Number |
13470073
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Immunology
|
Research Institution | Saga University (2004) 佐賀医科大学 (2001-2003) |
Principal Investigator |
KIMOTO Masao Saga University, Medicine, Professor, 医学部, 教授 (40153225)
|
Co-Investigator(Kenkyū-buntansha) |
NAGASAWA Kouhei Saga University, Medicine, Professor, 医学部, 教授 (00108721)
MIYAKE Kensuke The University of Tokyo, The Institute of Medical Science, Professor, 医科学研究所, 教授 (60229812)
|
Project Period (FY) |
2001 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥13,600,000 (Direct Cost: ¥13,600,000)
Fiscal Year 2004: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2003: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2002: ¥2,800,000 (Direct Cost: ¥2,800,000)
Fiscal Year 2001: ¥5,200,000 (Direct Cost: ¥5,200,000)
|
Keywords | MD-2 / recombinant protein / bacterial expression / CD14 / LBP / ligand / LPS / cytokine / リコンピナント蛋白 / TLR4 / RP105 / 川崎病 / アイソフォーム / 融合蛋白 / 変異蛋白 / MD-1 / SLE / 自己抗体 / CHO / ノックアウト / キメラ蛋白 / トランスフェクタント |
Research Abstract |
1.Analysis of the TLR and RP105 molecular structure : We obtained highly purified form of recombinant bacterial products of MD-2,CD14 and LBP. Using these purified proteins, we analyzed thier critical structures for binding to LPS. We also revealed the differential binding of CD14 and MD-2 to LPS. 2.Analysis of TLR4 and RP105 ligands : We found that MD-2 directly binds to LPS. On the other hand, MD-1 was found not to bind LPS directly, although LPS can signal through RP105/MD-1 molceule. We compared the LPS binding pattern between MD-1 and MD-2 using their site-specific mutant molecules. 3.Role of TLR4 and RP105 in immunological diseases : We found increased frequency of RP105-negative B cells in SLE patients. Culture of RP105-negative B cells resulted in the secretion of IgG and IgM, the production of these were augmented by SAC or IL-6 stimulation. RP105-negative B cells from SLE patients produced dsDNA antibodies. These results suggest that RP105-negative B cells are in an activated state and possibly involved in the production of auto-antibodies. 4.Manipulation of TLR4 and RP105 signal transduction : We found alternative spliced forms of MD-2 by RT-PCR. Such alternative form of MD-2 molecules may potentially function as dominant negative molecules for TLRA/MD-2 signaling, and may function as a potential tool for the manipulation of LPS signaling. We also obtained monoclonal antibodies against TLRA/MD-2. This mAb was found to transmit activation signals through TLRA/MD-2 and resulted in the secretion of pro-inflammatory cytokines.
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