MRI-based cell tracking of OATP-expressing cell transplants by pre-labeling with Gd-EOB-DTPA

Abstract

AbstractPurposeTo detect cell transplants labeled with a clinical gadolinium-based contrast agent as hyperintense signals using a clinically familiar T1-weighted MRI protocol.MethodsHEK293 cells were stably transduced to express human OATP1B3, a hepatic transporter that transport Gd-EOB-DTPA into cells that express the transporters, the intracellular accumulation of which cells causes signal enhancement on T1-weighted MRI. Cells were labeled in media containing Gd-EOB-DTPA for MRI evaluation and indocyanine green for cryofluorescence tomography validation. Labeled cells were injected into chicken hearts, in vitro, after which MRI and cryofluorescence tomography were performed in tandem.ResultsOATP1B3-expressing cells had substantially reduced T1 following labeling with Gd-EOB-DTPA in culture. Following their implantation into chicken heart, these cells were easily identified in T1-weighted MRI. Cryofluorescence tomography validated that the areas of signal enhancement in MRI overlapped with areas of indocyanine green signal, indicating that signal enhancement was due to the transplanted cells.ConclusionOATP1B3-expressing cells can be pre-labeled with Gd-EOB-DTPA prior to injection into tissue, affording the use of clinically familiar T1-weighted MRI to robustly detect cell transplants.