MagA is sufficient for producing magnetic nanoparticles in mammalian cells, making it an MRI reporter.
Magnetic resonance imaging (MRI) is routinely used to obtain anatomical images that have greatly advanced biomedical research and clinical health care today, but the full potential of MRI in providing functional, physiological, and molecular information is only beginning to emerge. In this work, we sought to provide a gene expression marker for MRI based on bacterial magnetosomes, tiny magnets produced by naturally occurring magnetotactic bacteria. Specifically, magA, a gene in magnetotactic bacteria known to be involved with iron transport, is expressed in a commonly used human cell line, 293FT, resulting in the production of magnetic, iron-oxide nanoparticles by these cells and leading to increased transverse relaxivity. MRI shows that these particles can be formed in vivo utilizing endogenous iron and can be used to visualize cells positive for magA. These results demonstrate that magA alone is sufficient to produce magnetic nanoparticles and that it is an appropriate candidate for an MRI reporter gene.
The Wallace H. Coulter Department of Biomedical Engineering, Emory University/Georgia Institute of Technology, Atlanta, Georgia 30329, USA.
Omar
O
Zurkiya
Anthony W S
AW
Chan
Xiaoping
X
Hu
D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D003287:Contrast Media / Q000737:chemistry; D004318:Doxycycline / Q000494:pharmacology; D005290:Ferric Compounds / Q000378:metabolism*; D005798:Genes, Bacterial; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D001426:Bacterial Proteins; D003287:Contrast Media; D005290:Ferric Compounds; D004318:Doxycycline