Yeh T C, Zhang W, Ildstad S T, Ho C
Pittsburgh NMR Center for Biomedical Research, Department of Biological Sciences, Carnegie Mellon University, PA 15213, USA.
Magn Reson Med. 1995 Feb;33(2):200-8. doi: 10.1002/mrm.1910330209.
Dynamic MRI tracking of rat T-cells in vivo is performed in rat testicles after labeling isolated rat T-cells in vitro with superparamagnetic dextran-coated iron-oxide particles, BMS180549. Tissue inflammation induced by the local injection of the calcium ionophore, A23187, is used to attract labeled T-cells. Gradient-echo MR images of rat testicles show a statistically significant decrease (4%) of the signal intensity in areas of injection of A23187 as early as 30 min after intravenous infusion of 2 x 10(8) labeled T-cells. The signal change reaches its maximum (6-7% decrease) at about 60-120 min after cell infusion. T2-mapping also shows a decrease of T2 in the areas with A23187. Image quantitation, which includes a chemical-shift effect, significantly enhances the sensitivity for detection of superparamagnetically labeled T-cells. Localization of labeled T-cells in rat testicles has been verified by fluorescence microscopy studies of T-cells co-labeled with a lipophilic fluorescent carbocyanine dye, 1,1-dioctadecyl-3,3,3',3'-tetramethyl-lindocarbocyanine perchlorate. These results represent the first successful demonstration of dynamic tracking of specific cells in vivo using MRI.
在用超顺磁性葡聚糖包被的氧化铁颗粒BMS180549体外标记分离的大鼠T细胞后，在大鼠睾丸中进行大鼠T细胞体内动态磁共振成像（MRI）追踪。通过局部注射钙离子载体A23187诱导组织炎症，以吸引标记的T细胞。大鼠睾丸的梯度回波MR图像显示，在静脉输注2×10⁸个标记的T细胞后30分钟，A23187注射部位的信号强度就出现了统计学上的显著下降（4%）。信号变化在细胞输注后约60 - 120分钟达到最大值（下降6 - 7%）。T2映射也显示A23187区域的T2降低。包括化学位移效应的图像定量显著提高了检测超顺磁性标记T细胞的灵敏度。通过对与亲脂性荧光碳菁染料1,1 - 二辛基 - 3,3,3',3' - 四甲基 - 吲哚碳菁高氯酸盐共标记的T细胞进行荧光显微镜研究，已证实标记的T细胞在大鼠睾丸中的定位。这些结果代表了首次成功利用MRI在体内对特定细胞进行动态追踪。
