CAREER: Imaging Protease Activity In Vivo with the T2/T1 Signal Quenching Strategy

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

0546962 Murthy The applicant proposes to use the T1/T2 quenching effect for imaging protease activity, and he has demonstrated in preliminary results a combined T2 and T1 agent (Dysprosium and Gadolinium connected by a PEG chain) which has very small modulation to the MR signal intensity, due to the offsetting effect of the T2 and T1 agents. By design, the T2 agent is attached to the PEG chain through a trypsin cleavage site, which can be broken by a target enzyme (e.g. trypsin). Once detached from the PEG chain, the T2 agent loses its modulation effect on the MR signal, resulting in an intensity increase reflecting the protease activity. The applicant ultimately seeks to apply this methodology to image the activity of MMP-7 in mouse tumors, since it is over-expressed in several cancers.