Optical Imaging Research

Optical imaging for preclinical testing of novel anticancer therapeutics

Why choose optical imaging? Because optical imaging is:

Non invasive
Efficient
Cost-effective

Optical imaging is a non invasive technology allowing to visualize molecular events in real-time and over time in the same animal, providing an optimal tool for studying tumor physiology, metastasis pattern, and tumor response to drug treatment. By labelling a target molecule, antibody, gene or protein with fluorescent agents, scientists employ optical imaging for preclinical testing of novel anticancer therapeutics. Following a single animal over time is cost-effective and allows researchers to monitor disease progression, together with the outcome and the effects of interventions. [J Nucl Med 2007: 48 (9):1501-10, J Med Chem. 2007 Sep 20;50(19):4759-65]

Imaging technologies are increasingly used as core technologies in bio-pharmaceutical research and development, both in the preclinical and clinical phases of the research and development process. Traditional survival-based endpoints are fast going out of fashion as a way of measuring drug efficacy, in favor of in vivo imaging. The reason for this shift is both time and money. FDA regulating body recently issued guidelines permitting the use of innovative molecular imaging technologies to track drug “microdoses” in preclinical studies in order to allow pharmaceutical companies to enter into phase I faster.

Examples of Optical Imaging Analysis

Optical imaging tumor’s progression
Biodistribution over time of a biomarker labelled with Cy5.5 in a mouse bearing a tumor.

Optical imaging lymphonodes’ progression
Biodistribution over time of a biomarker labelled with Cy5.5 in districts different from the primary tumor region, i.e. lymphonodes.

Temporal Point Spread Function
The graph represents the intensity and the depth of the signal. Intensity is represented by the high of the peak in the Y axis (sum of photons) while depth is represented by the position of the peak in the X axis. It is possible to compare intensities and depths belonging to different regions of the same scan or to different regions of different scans.

Lifetime graph in Time Domain Imaging
Lifetime means the length of time it takes for a fluorophore (in this case for Cy5.5) to return to its ground state following excitation. Lifetime value is the slope of the decay curve, where a short lifetime corresponds to a steep slope. Free Cy5.5 lifetime is around 1.