Novel Non-Immunogenic Positron Emission Tomography Gene Reporter

Summary

UCLA researchers in the Department of Pharmacology and Department of Microbiology, Immunology, & Molecular Genetics have developed a novel positron emission tomography reporter gene to preferentially trap radiolabeled deoxycytidine analogs.

Background

Positron Emission Tomography (PET) is a non-invasive imaging tool that is used to monitor the metabolic activity of tissues within a patient’s body. PET scanners detect positron emitting isotopes or probes that are taken up by biologically active cells. This technique has been modified as a reporter system for cellular imaging. In a PET reporter gene system, a reporter gene is introduced to cells of interest that encodes either an enzyme or a receptor that functions to induce the accumulation of PET probes into or onto a cell surface. Once the cells are labeled by the presence of the PET probes, they can be detected within the body by a PET scanner, thus allowing downstream image analysis of cells of interest.

Innovation

UCLA researchers have developed a novel gene that encodes an enhanced version of deoxycytidine kinase (EdCK) to function as a PET reporter. EdCK preferentially traps radiolabeled analogs of deoxycytidine, a novel field of probes. This EdCK has been modified to achieve high levels of expression and reporter activity within cells, making it a robust system for labeling cells of interest. Furthermore, EdCK is a human gene and therefore would not cause an immunogenic response in human subjects, making it a potential tool for labeling cells for cell transplantation therapy.

Applications

• Targeted cell labeling in vitro and in vivo

Advantages

• Utilizes novel fluorinated deoxycytidine analogs (which may have improved pharmacokinetics and signal-to-noise ratios compared to currently used probes) 
• Non-immunogenic

State Of Development

Testing in cell culture to determine the efficacy of EdCK compared to dCK as a PET reporter.