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MAGNETIC FIELD EFFECTS ON MACROPHAGES

磁场对巨噬细胞的影响

基本信息

批准号：
3180995
负责人：
Joseph D Brain
金额：
$ 16.08万
依托单位：
HARVARD MEDICAL SCHOOL
依托单位国家：
美国
项目类别：
财政年份：
1985
资助国家：
美国
起止时间：
1985-12-01 至 1992-11-30
项目状态：
已结题

项目摘要

In vivo nuclear magnetic resonance (NMR) exposes living tissue to large magnetic fields. Tissue constituents interact weakly with magnetic fields, and the direct effects of magnetic fields on cellular, biochemical, and genetic processes have not been reproducibly established. However, microscopic ferromagnetic particles be present as contaminants in the lungs and other organs. in many occupational settings, humans inhale magnetic-particle aerosols; a fraction of the particles are retained in the lungs and are ingested by pulmonary macrophages. Strong magnetic fields can cause these magnetic particles to move, rotate, and agglomerate. The toxicology of NMR fields on cells and tissues containing ferromagnetic particles is unknown. Years 01 and 02 of the project demonstrated that microscopic magnetic particles can be observed both optically and magnetically in cells. Moreover, such particles can serve as an experimental indicator of macrophage function by noninvasively providing information on the motions of cell organelles. We found that for phagocytized particles, cytoplasmic motions rotate particles and produce detectable changes in the magnetic field. In addition, intracellular particles can be twisted by an applied external field, which allows measurement of cytosol viscoelasticity. The proposed researeh will examine magnetie field effects on particle-containing lung macrophages. In years 04-06 we will address the following questions: (1) Can magnetic forces overcome the motile forces generated by the macrophage cytoplasm? Can magnetic forces restrain chemotaxis? We will quantify the magnitude of traction forces magnetometrically. (2) Can motion imposed by magnet fields on magnetic-particle containing cell organelles modulate the fusion of phagocytic and lysosomal vesicles? (3) Can alterations in cell organelle motions, magnetometrically detected, be used to identify the existence and activity of an intracellular infection (e.g., AIDS) in macrophages? The goal is to examine how phagocytized ferromagnetic particles modify cell function when cells are exposed to strong magnetic fields. At the same time, we will measure the forces generated in cell motility, we will examine the role of organelle motions in phagolysosome processing, and we will identify changes in motion and rheology caused by viral infection.

体内核磁共振 (NMR) 将活组织暴露于大磁场。组织成分与以下物质的相互作用较弱磁场以及磁场对物体的直接影响细胞、生物化学和遗传过程尚未被可重复建立。然而，微观铁磁颗粒作为污染物存在于肺部和其他器官中。在许多职业环境中，人类吸入磁性粒子气溶胶；一小部分颗粒保留在肺部被肺巨噬细胞摄取。强磁场可以导致这些磁性颗粒移动、旋转和聚集。核磁共振场对细胞和组织的毒理学铁磁颗粒未知。该项目的第一年和第二年表明，微观磁性颗粒可以通过光学和磁力观察在细胞中。此外，此类颗粒可以作为实验通过非侵入性提供巨噬细胞功能的指标有关细胞器运动的信息。我们发现对于吞噬颗粒，细胞质运动使颗粒旋转，产生可检测到的磁场变化。此外，细胞内颗粒可以通过施加的外部扭曲场，可以测量细胞质粘弹性。拟议的研究将检查磁场对含有颗粒的肺巨噬细胞。在 04-06 年，我们将解决以下问题： (1) 磁力能否克服磁力产生的动力？巨噬细胞的细胞质？磁力可以抑制趋化性吗？我们将量化牵引力的大小磁力测量。 (2) 磁场可以对磁性粒子施加运动吗含有细胞器调节吞噬细胞和溶酶体囊泡？ (3) 细胞器运动的改变，磁力测量检测到，用于识别某物的存在和活动巨噬细胞的细胞内感染（例如艾滋病）？目的是检查铁磁颗粒如何被吞噬当细胞暴露于强磁场时改变细胞功能字段。同时，我们将测量产生的力细胞运动，我们将研究细胞器运动在细胞运动中的作用吞噬溶酶体处理，我们将识别运动的变化和病毒感染引起的流变学。