Identify the commensal bacteria that development of colitis

Research Project

Project/Area Number	26850206
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Integrative animal science
Research Institution	Tokyo Medical and Dental University
Principal Investigator	Nakanishi Yusuke 東京医科歯科大学, 難治疾患研究所, 助教 (20579411)
Project Period (FY)	2014-04-01 – 2016-03-31
Project Status	Completed (Fiscal Year 2015)
Budget Amount *help	¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000) Fiscal Year 2015: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000) Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
Keywords	炎症性腸疾患 / マクロファージ / 共生細菌
Outline of Final Research Achievements	Using a mouse dextran sodium sulfate (DSS)-induced colitis model, we found that commensal Gram-positive bacteria trigger the mobilization of inflammatory monocyte and macrophage. TNF is a representative inflammatory cytokine that aggravates colitis and a target for therapy, predominantly produced by monocyte and macrophage. Interestingly, pretreating mice with vancomycin, which eliminated Gram-positive bacteria　significantly reduced the severity of colitis, evaluated by the colon length, cytokine level, histological analysis etc. In addition, 16S rRNA analysis showed that vancomycin treatment dramatically reduced Lachnospiraceae, the most abundant order of Clostridiales in untreated control mice. We also suggested that this strain stimulated the local production of chemokine by colonic epithelial cells, which induce the mobilization of monocyte/macrophage into the inflamed colon.