Zimmer C, Weissleder R, Poss K, Bogdanova A, Wright S C, Enochs W S
Department of Radiology, Massachusetts General Hospital, Boston, USA.
Radiology. 1995 Nov;197(2):533-8. doi: 10.1148/radiology.197.2.7480707.
To determine whether phagocytosis can be observed in vivo in glioma cells.
Rat C6 glioma cells were studied in culture and after intracerebral implantation into 13 rats. Monocrystalline iron oxide nanoparticles (MION), a model marker of phagocytosis, was administered intravenously to tumor-bearing rats at 2-20 mg of iron per kilogram. Magnetic resonance (MR) imaging was performed at multiple time points.
Glioma cells in culture showed uptake of MION in amounts of up to 10 ng of iron per 10(6) cells, corresponding to approximately 50,000 particles per cell. Fluorescently labeled MION was found to be located primarily in tubular lysosomes. Intracerebral gliomas showed characteristic changes in signal intensity at MR imaging that peaked 12 hours after administration of MION and lasted up to 5 days; these changes corresponded to uptake and subsequent biodegradation of MION by tumor cells.
Phagocytosis of glioma cells can be detected in vivo with iron oxide-enhanced MR imaging, and this may permit accurate delineation of tumor margins.
确定是否能在体内观察到胶质瘤细胞的吞噬作用。
对大鼠C6胶质瘤细胞进行体外培养研究，并将其植入13只大鼠脑内后进行研究。将单晶体氧化铁纳米颗粒（MION）作为吞噬作用的模型标记物，以每千克2 - 20毫克铁的剂量静脉注射给荷瘤大鼠。在多个时间点进行磁共振（MR）成像。
体外培养的胶质瘤细胞显示对MION的摄取量高达每10⁶个细胞10纳克铁，相当于每个细胞约50,000个颗粒。发现荧光标记的MION主要位于管状溶酶体中。脑内胶质瘤在MR成像中显示出信号强度的特征性变化，在注射MION后12小时达到峰值，并持续长达5天；这些变化对应于肿瘤细胞对MION的摄取及随后的生物降解。
通过氧化铁增强的MR成像可在体内检测到胶质瘤细胞的吞噬作用，这可能有助于准确勾勒肿瘤边界。
