Molecular Imaging of Endothelial Adhesion Molecules - Adhesion Molecules - page 62

in diameter) were conjugated to a mixture of ICAM-1 antibody and 64Cu-DOTA-
IgG. h e lungs of mice administered the anti-ICAM nanoparticles were clearly
seen using small-animal PET up to 24 hr at er administration (Rossin et al. 2008).
For the lattter, abegrin, a monoclonal antibody to human α v β 3 integrin, was used
to target a 90 Y radionuclide to glioblastoma multiforme in a mouse model.
Such widespread applications suggest that nuclear molecular imaging, in
combination with anatomical imaging from MRI or CT, is likely to play a signii cant
role in developing viable clinical methods of molecular imaging of vascular disease
(Fig. 3) .
Fig. 3 Human Molecular Imaging using PET. Nuclear: Use of a novel α v β 3 -targeting PET agent
(F-Galakto-RGD) to assess integrin expression in a 35-year-old male several weeks following a
myocardial infarction (C, F). Focal tracer retention is seen in the infarcted area previously dei ned
using late-gadolinium-enhanced MRI (A, D) and perfusion PET (B, E) imaging. h is signal may
rel ect angiogenesis within the healing area (arrows). With permission from Makowski (2008).
OPTICAL IMAGING
While ultrasound, MRI, or nuclear imaging may prove to be the i rst detection
modalities to reach the clinical goal of non-invasive detection of adhesion
molecule expression, optical imaging using l uorochromes will play an important
role in the development of molecular imaging techniques. Optical imaging can be
performed rapidly and at relatively low cost, and as such can be used to screen
candidate probes before launching into more expensive and complicated in vivo
imaging experiments, for example to allow quantii cation of probe specii city and
sensitivity (Fig. 4) .
Optical imaging requires the introduction of a l uorescent probe that is targeted
to a specii c adhesion molecule epitope. Several dif erent reporter technologies can