Combined two-photon luminescence microscopy and OCT for macrophage detection in the hypercholesterolemic rabbit aorta using plasmonic gold nanorose
Article first published online: 3 JAN 2012
Copyright © 2012 Wiley Periodicals, Inc.
Lasers in Surgery and Medicine
Volume 44, Issue 1, pages 49–59, January 2012
How to Cite
Wang, T., Mancuso, J. J., Kazmi, S.M. S., Dwelle, J., Sapozhnikova, V., Willsey, B., Ma, L. L., Qiu, J., Li, X., Dunn, A. K., Johnston, K. P., Feldman, M. D. and Milner, T. E. (2012), Combined two-photon luminescence microscopy and OCT for macrophage detection in the hypercholesterolemic rabbit aorta using plasmonic gold nanorose. Lasers Surg. Med., 44: 49–59. doi: 10.1002/lsm.21153
- Issue published online: 13 JAN 2012
- Article first published online: 3 JAN 2012
- Manuscript Accepted: 22 NOV 2011
- American Society for Laser Medicine and Surgery
- Veterans Administration Merit Grant
- Welch Foundation Grant. Grant Number: F-1319
- NSF Grant. Grant Number: CBET-0968038
- Department of Energy Center for Frontiers of Subsurface Energy Security
- two-photon luminescence microscopy;
- optical coherence tomography;
- photothermal wave imaging
Background and Objectives
The macrophage is an important early cellular marker related to risk of future rupture of atherosclerotic plaques. Two-channel two-photon luminescence (TPL) microscopy combined with optical coherence tomography (OCT) was used to detect, and further characterize the distribution of aorta-based macrophages using plasmonic gold nanorose as an imaging contrast agent.
Study Design/Materials and Methods
Nanorose uptake by macrophages was identified by TPL microscopy in macrophage cell culture. Ex vivo aorta segments (8 × 8 × 2 mm3) rich in macrophages from a rabbit model of aorta inflammation were imaged by TPL microscopy in combination with OCT. Aorta histological sections (5 µm in thickness) were also imaged by TPL microscopy.
Merged two-channel TPL images showed the lateral and depth distribution of nanorose-loaded macrophages (confirmed by RAM-11 stain) and other aorta components (e.g., elastin fiber and lipid droplet), suggesting that nanorose-loaded macrophages are diffusively distributed and mostly detected superficially within 20 µm from the luminal surface of the aorta. Moreover, OCT images depicted detailed surface structure of the diseased aorta.
Results suggest that TPL microscopy combined with OCT can simultaneously reveal macrophage distribution with respect to aorta surface structure, which has the potential to detect vulnerable plaques and monitor plaque-based macrophages overtime during cardiovascular interventions. Lasers Surg. Med. 44:49–59, 2012. © 2012 Wiley Periodicals, Inc.