Abstract
Purpose: :
Quantum dot semiconducting nanocrystals have been harnessed for molecular imaging applications due to their size-tunable emission spectra and high photostability. We utilized QD for the multiplexed in vivo and ex vivo imaging of inflammatory mediators in mouse models of atherosclerosis.
Methods: :
We performed bioimaging of ApoE -/- mouse models of atherosclerosis using a fluorescence imaging system. Atheroma components in retinal and aortic tissues, including cell adhesion molecules, leukocytes, and lipids were analyzed using QD immunolabeling as well as conventional methods.
Results: :
QD molecular probes based on monoclonal antibodies or solid lipids were specific for their targets in vasculature. QD coated with internalization peptides were not cytotoxic to ex vivo labeled monocytes and T cells, which could be detected in circulation over 24 hrs. post-injection, as well as post-mortem tissues, with high signal to noise ratios. Dye-labeled positive control antibodies and stains confirmed specificity of QD targeting.
Conclusions: :
Our preliminary findings warrant the further investigation of QD as optical probes for the bioimaging of vascular disease markers. Multiple components of the atherosclerotic cascade were readily identified with our imaging strategy. Such approaches should serve as useful tools for the detailed study of cellular and molecular mediators of disease, using the non-invasive, optically accessible retinal vasculature as an in vivo imaging window. Future work is directed toward preclinical imaging techniques to diagnose atherosclerosis using retinal fluorescence imaging with QD probes.
Keywords: inflammation • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina