Related Experiment Video
Updated: May 17, 2026
Intravital Microscopy of Monocyte Homing and Tumor-Related Angiogenesis in a Murine Model of Peripheral Arterial Disease
Published on: August 26, 2017
High-resolution optical mapping of inflammatory macrophages following endovascular arterial injury
Amit Saxena1, Chase W Kessinger, Brian Thompson
1Cardiovascular Research Center, Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Room 3206, Simches Research Building, 185 Cambridge Street, Boston, MA 02114, USA.
Purpose:
Inflammation following arterial injury mediates vascular restenosis, a leading cause of cardiovascular morbidity. Here we utilize intravital microscopy (IVM) and a dextran-coated nanosensor to spatially map inflammatory macrophages in vivo following endovascular injury of murine carotid arteries.
Procedures:
C57Bl/6 mice (n = 23) underwent endovascular guidewire carotid arterial injury. At day 14 or day 28 post-injury, mice underwent fluorescence IVM, 24 h after injection with the near-infrared fluorescent macrophage nanosensor CLIO-VT680. Adventitial collagen was concomitantly imaged using second harmonic generation (SHG) IVM. Correlative fluorescence microscopy and immunohistochemistry were performed.
Results:
Two-plane IVM reconstructions detected macrophage inflammation in the arterial wall that was elevated at day 14 compared to day 28 animals (P < 0.05). SHG-based collagen imaging of the outer arterial wall facilitated analysis of the macrophage-rich, inflamed neointima. Histological analyses and fluorescence microscopy data demonstrated increased macrophage infiltration in day 14 compared to day 28 neointima.
Conclusions:
We demonstrate that the macrophage response to arterial injury can be imaged in vivo using IVM-based molecular imaging, and shows a higher macrophage influx at day 14 compared to day 28 post-injury.
