Project/Area Number |
63850190
|
Research Category |
Grant-in-Aid for Developmental Scientific Research (B).
|
Allocation Type | Single-year Grants |
Research Field |
発酵工学
|
Research Institution | Tokyo University of Agriculture and Technology |
Principal Investigator |
MATSUNAGA Tadashi Tokyo University of Agriculture & Technology, Department of Biotechnology, Professor, 工学部, 教授 (10134834)
|
Co-Investigator(Kenkyū-buntansha) |
NAKAMURA Kayoko Keio University, Department of Radiology, Lecturer, 医学部, 講師
|
Project Period (FY) |
1988 – 1990
|
Project Status |
Completed (Fiscal Year 1990)
|
Budget Amount *help |
¥8,000,000 (Direct Cost: ¥8,000,000)
Fiscal Year 1990: ¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1989: ¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1988: ¥4,100,000 (Direct Cost: ¥4,100,000)
|
Keywords | magnetotactic bacteria / leucocyte / magnetic separation / lymphocyte / macrophage / bacterial magnetic particle / 磁気微粒子 / 顆粒球 / マクロファージ |
Research Abstract |
Magnetotactic bacteria which orient and swim along a geomagnetic field have been found in fresh and marine sediments. These bacteria contain magnetic particles consisting of magnetite in a controlled size (50-100 nm). Recently, the investigator's group reported that bacterial magnetic particles can be introduced into red blood cells by cell fusion using polyethylene glycol. If magnetic particles are introduced into leucocytes consisting of lymphocytes and phagocytes (granulocytes and monocytes), they can be used for therapy by being guided to the objective position by applying a magnetic field. In this research, magnetotactic bacteria were introduced into granulocytes and monocytes by phagocytosis. The movement of phagocytes containing bacterial magnetic particles was magnetically controlled and phagocytes were separated from lymphocytes by applying magnetic field. Application of magneto-sensitive leucocytes (eg. introduction into animal) were also carried out. The number of phagocytes containing bacterial magnetic particles (magneto-sensitive cells) became constant after 90 min incubation, and viable phagocytes contained about 20 - 40 cells of magnetotactic bacteria. Granulocytes and monocytes containing bacterial magnetic particles were separated by a samarium-cobalt magnet from lymphocytes. After separation, 89% of lymphocytes were recovered and 95% of the cells were viable. The contamination of phagocytes in the recovered lymphocytes was below 0.8%. Magnetosensitive granulocytes and monocytes were removed by applying a magnetic field. The nitroblue tetrazolium reducing, chemotactic and phagocytic abilities of phagocytes ingesting magnetotactic bacteria were 84%, 88% and 87% respectively after 1 hr incubation.
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