Abstract
Purpose
The purpose of this study is to evaluate if the differential exchange rates with bulk water between amine and amide protons can be exploited using chemical exchange saturation transfer magnetic resonance (CEST-MR) to monitor the release of glutamate induced by carboxypeptidase G2 (CPG2), an enzyme utilized in cancer gene therapy.
Procedures
Z spectra of solutions of the CPG2 substrate, 3,5-difluorobenzoyl-L-glutamate (amide), and glutamate (amine) were acquired at 11.7 T, 37 °C, across different pH (5–8). The ability of CEST-MR to monitor CPG2-mediated release of glutamate was assessed in extracts of CPG2-expressing cancer cells and purified solution of CPG2.
Results
The addition of CPG2 to a solution containing 3,5-difluorobenzoyl-L-glutamate led to a marked and progressively increasing CEST effect (+3 ppm), concomitant with the time-dependent release of glutamate induced by CPG2.
Conclusion
CEST-MR allows the detection of CPG2 activity in vitro and supports the translation of CEST-MRI to assess CPG2-based gene therapy in vivo.
The purpose of this study is to evaluate if the differential exchange rates with bulk water between amine and amide protons can be exploited using chemical exchange saturation transfer magnetic resonance (CEST-MR) to monitor the release of glutamate induced by carboxypeptidase G2 (CPG2), an enzyme utilized in cancer gene therapy.
Procedures
Z spectra of solutions of the CPG2 substrate, 3,5-difluorobenzoyl-L-glutamate (amide), and glutamate (amine) were acquired at 11.7 T, 37 °C, across different pH (5–8). The ability of CEST-MR to monitor CPG2-mediated release of glutamate was assessed in extracts of CPG2-expressing cancer cells and purified solution of CPG2.
Results
The addition of CPG2 to a solution containing 3,5-difluorobenzoyl-L-glutamate led to a marked and progressively increasing CEST effect (+3 ppm), concomitant with the time-dependent release of glutamate induced by CPG2.
Conclusion
CEST-MR allows the detection of CPG2 activity in vitro and supports the translation of CEST-MRI to assess CPG2-based gene therapy in vivo.
| Original language | English |
|---|---|
| Pages (from-to) | 152-157 |
| Number of pages | 6 |
| Journal | Molecular Imaging and Biology |
| Volume | 16 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 17 Aug 2013 |
Research Beacons, Institutes and Platforms
- Manchester Cancer Research Centre
