Seeing is Believing, Only Without the Background
Thomas J. Meade
Thomas J. Meade, Ph. D.
Thomas J. Meade is the Eileen M. Foell Professor of Chemistry, Biochemistry and Molecular and Cell Biology, Neurobiology and Physiology and Radiology at Northwestern University.
Dr. Meade pioneered the use of bioactivated MR contrast agents for gene expression and cell patterning by MRI. He has founded three companies—Clinical Micro Sensors, Metaprobe and Ohmx—that are developing hand-held detection devices for protein and DNA detection and bioactivated MR contrast agents for clinical imaging and hold more than 50 U.S. patents.
Research
Fundamental biological and clinical questions have driven technological advances in an area of research known as biological molecular imaging. The direct observation of ongoing developmental events in living embryos and the descendants of individual precursors in an intact embryo can be labeled by microinjection of stable, nontoxic, MR lineage tracers. Since a complete time-series of high-resolution three-dimensional MR images can be analyzed forward or backward in time, it is possible to reconstruct the cell divisions and cell movements responsible for any particular descendant(s).
In order to understand the mechanisms of gene expression in whole animals, we have developed a library of multimodal MR probes that are biochemically activated in vivo. The lanthanide chelates modulate fast water exchange with the paramagnetic center, yielding distinct relaxivity states. The modualtion is triggered by two types of events: enzymatic processing of the contrast agent and the reversible binding of an intracellular messenger.