Michael McMahon, Ph.D.

Michael McMahon
Michael McMahon
Research Scientist, FM Kirby Research Center for Functional Brain Imaging

Kennedy Krieger Institute
707 N. Broadway
Baltimore, MD 21205
Phone: (443)923-9356
Email: mcmahon@kennedykrieger.org

Dr. Michael T. McMahon is an associate professor in the Department of Radiology at the Johns Hopkins School of Medicine and a research scientist in the F.M. Kirby Research Center for Functional Brain Imaging at Kennedy Krieger Institute.

Biographical Sketch:

Dr. McMahon obtained his bachelor’s degree in physics at the University of Richmond and earned a doctoral degree in physical chemistry at the University of Illinois at Urbana-Champaign specializing in solid-state NMR spectroscopy. He was awarded an NIH NRSA postdoctoral fellowship under Robert Griffin, Director of the Francis Bitter Magnet Laboratory at Massachusetts Institute of Technology. He began working in the field of MRI research in the F.M. Kirby Research Center for Functional Brain Imaging and the MRI division of Radiology at Johns Hopkins School of Medicine, first as research associate (2003), then assistant professor (2006), and now associate professor (2012). He has been elected program director at the International Society for Magnetic Resonance in Medicine (ISMRM) and recognized as a distinguished reviewer for the journal Magnetic Resonance in Medicine.

Research Summary:

Chemical Exchange Saturation Transfer (CEST) has emerged as an MRI contrast mechanism well suited for molecular imaging. This mechanism can be used to detect small amounts of contrast agent through saturation of rapidly exchanging protons on compounds provided that these protons are in the proper exchange regime. Dr. McMahon’s research group has been focused on the development of MRI technology to detect organic molecules and macromolecules using CEST imaging and exploiting this technology for monitoring therapy. This includes hybrid biomaterials which both support cell transplants and allow the monitoring of environmental pH to determine whether changes are taking place that may signal rejection of the transplanted cells. The group is also focused on the development of CEST imaging tools for monitoring drug therapy and for monitoring gene expression.

The ultimate goal is to translate these imaging technologies onto the clinical MRI scanners available at the F.M. Kirby Research Center.

Research Publications:

Song X, Yang X, Ray Banerjee S, Pomper MG, McMahon MT. (2015). Anthranilic acid analogs as diamagnetic CEST MRI contrast agents that feature an intramolecular-bond shifted hydrogen. Contrast Media & Molecular Imaging, 10(1), 74-80.

Oskolkov N, Bar-Shir A, Chan KW, Song X, van Zijl PC, Bulte JW, Gilad AA, McMahon MT. (2015). Biophysical characterization of human protamine-1 as a responsive CEST MR contrast agent. ACS Macro Letters, 4(1), 34-38.

Song X, Xu J, Xia S, Yadav NN, Lal B, Laterra J, Bulte JW, van Zijl PC, McMahon MT. (2015). A Multi-echo Length and Offset VARied Saturation (MeLOVARS) Method for Improved CEST Imaging. Magnetic Resonance in Medicine, 73(2), 488-496.

Chan KW, Yu T, Qiao Y, Liu Q, Yang M, Patel H, Liu G, Kinzler KW, Vogelstein B, Bulte JW, van Zijl PC, Hanes J, Zhou S, McMahon MT. (2014). A diaCEST MRI approach for monitoring liposomal accumulation in tumors. Journal of Controlled Release, 180, 51-59.

Chan KW, Liu G, Song X, Kim H, Yu T, Arifin DR, Gilad AA, Hanes J, Walczak P, van Zijl PC, Bulte JW, McMahon MT. (2013). MRI-detectable pH nanosensors incorporated into hydrogels for in vivo sensing of transplanted-cell viability. Nature Materials, 12(3), 268-275.

Yang X, Song X, Li Y, Liu G, Ray Banerjee S, Pomper MG, McMahon MT. (2013). Salicylic acid and analogues as diaCEST MRI contrast agents with highly shifted exchangeable proton frequencies. Angewandte Chemie, 52(31), 8116-8119.

Song X, Gilad AA, Joel S, Liu G, Bar-Shir A, Liang Y, Gorelik M, Pekar JJ, van Zijl PC, Bulte JW, McMahon MT. (2012). CEST phase mapping using a length and offset varied saturation (LOVARS) scheme. Magnetic Resonance in Medicine, 68(4), 1074-1086.

McMahon MT, Gilad AA, DeLiso MA, Berman SM, Bulte JW, van Zijl PC. (2008). New "multicolor" polypeptide diamagnetic chemical exchange saturation transfer (DIACEST) contrast agents for MRI. Magnetic Resonance in Medicine, 60(4), 803-812.

Gilad AA, McMahon MT, Walczak P, Winnard PT Jr, Raman V, van Laarhoven HW, Skoglund CM, Bulte JW, van Zijl PC. (2007). Artificial reporter gene providing MRI contrast based on proton exchange. Nature Biotechnology, 25(2), 217-219.

McMahon MT, Gilad AA, Zhou J, Sun PZ, Bulte JW, van Zijl PC. (2006). Quantifying exchange rates in chemical exchange saturation transfer agents using the saturation time and saturation power dependencies of the magnetization transfer effect on the magnetic resonance imaging signal (QUEST and QUESP): Ph calibration for poly-L-lysine and a starburst dendrimer. Magnetic Resonance in Medicine, 55(4), 836-847.