| Autor: |
Allouche-Arnon H; Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel., Montrazi ET; Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 7610001, Israel., Subramani B; Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel., Fisler M; Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel., Spigel I; Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel., Frydman L; Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 7610001, Israel., Mehlman T; Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot 7610001, Israel., Brandis A; Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot 7610001, Israel., Harris T; Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel., Bar-Shir A; Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot 7610001, Israel. |
| Abstrakt: |
The ability to obtain quantitative spatial information on subcellular processes of deep tissues in vivo has been a long-standing challenge for molecular magnetic resonance imaging (MRI) approaches. This challenge remains even more so for quantifying readouts of genetically engineered MRI reporters. Here, we set to overcome this challenge with a molecular system designed to obtain quantitative 2 H-MRI maps of a gene reporter. To this end, we synthesized deuterated thymidine, d 3 -thy, with three magnetically equivalent deuterons at its methyl group (-CD 3 ), showing a singlet peak with a characteristic 2 H-NMR frequency (δ = 1.7 ppm). The upfield 3.0 ppm offset from the chemical shift of the HDO signal (δ = 4.7 ppm) allows for spectrally resolving the two 2 H NMR signals and quantifying the concentration of d 3 -thy based on the known concentration of a tissue's HDO. Following systemic administration of d 3 -thy, its accumulation as d 3 -thy monophosphate in cells expressing the human thymidine kinase 1 (hTK1) transgene was mapped with 2 H-MRI. The data obtained in vivo show the ability to use the d 3 -thy/hTK1 pair as a reporter probe/reporter gene system to quantitatively map transgene expression with MRI. Relying on a structurally unmodified reporter probe ( d 3 -thy) to image the expression of unmutated human protein (hTK1) shows the potential of molecular imaging with 2 H-MRI to monitor gene reporters and other relevant biological targets. |
