Patent ID: 7378078

Claim:
A method of imaging, comprising: a) providing i) cells, ii) a mammalian subject, wherein said mammalian subject has endogenous expression of a target caspase, iii) a genetic construct, wherein said genetic construct encodes a chimeric polypeptide, where said chimeric polypeptide comprises 1) an illumination domain wherein said illumination domain comprises a bioluminescence imaging unit, 2) at least two silencing domains, wherein said at least two silencing domains comprise a receptor ligand binding unit, wherein said receptor ligand binding unit is a steroid hormone receptor ligand binding unit, and 3) a target caspase recognition site, wherein said target caspase recognition site is configured to bind whith an endogenous target caspase expressed whithin said subject; wherein said target caspase recongnition site comprises a caspase-3 recognition site, wherein said caspase-3 recognition site comprise DEVD; and iv) an imaging agent, and b) transfecting said cells with said genetic construct; c) implanting said cells into said mammalian subject; d) administering said imaging agent to said mammalian subject; and e) measuring the activity of said endogenous target caspase by detecting signal from said illumination unit.