Need of Multimodal SPECT/MRI for Tracking of ¹¹¹In-Labeled Human Mesenchymal Stem Cells in Neuroblastoma Tumor-Bearing Mice

Abstract

Tumor-homing is a complex, multistep process used by many cells, like mesenchymal stem cells (MSCs), to travel from a distant location to a tumor. The purpose of this study is to investigate the applicability of ¹¹¹In-oxine for tracking human MSCs in vivo with single photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI). ¹¹¹In labeled hMSCs (10⁶ cells) were infused intraperitoneally in neuroblastoma tumor-bearing mice, and SPECT/MRI images were performed 24 and 48 hour afterwards. High initial hMSC localization occurred in the abdomen cavity and 48 hour later hMSC-injected animals showed tumor uptake. MRI information was essential to properly define Regions of Interest on the images. Tracking ¹¹¹In labeled hMSC combining SPECT and MRI is feasible and may be transferable to human studies.