Tracking of NK Cells by Positron Emission Tomography Using 89 Zr-Oxine Ex Vivo Cell Labeling.

A Zr-oxine ex vivo cell labeling method for tracking various cells by positron emission tomography (PET) imaging has recently been developed. Zr-oxine is synthesized from oxine and Zr-chloride, which was converted from Zr-oxalate, with neutralization. To track migration of natural killer (NK) cells in vivo in real time by PET imaging, NK cells are labeled with Zr-oxine ex vivo and infused to a recipient. The labeling is performed by mixing Zr-oxine solution to NK cell suspension at room temperature, followed by washing. Care should be taken to label the cells at optimal radioactivity doses that maintain their viability and functionality. Zr-oxine labeled NK cells can be tracked for their migration and distribution by PET/computed tomography imaging for at least 7 days. Of note, this protocol is applicable to other types of cells.