Molecular Imaging and Biology

, Volume 13, Issue 6, pp 1163–1172

Trafficking of a Dual-Modality Magnetic Resonance and Fluorescence Imaging Superparamagnetic Iron Oxide-Based Nanoprobe to Lymph Nodes

  • Ambika Bumb
  • Celeste A. S. Regino
  • Jackson G. Egen
  • Marcelino Bernardo
  • Peter J. Dobson
  • Ronald N. Germain
  • Peter L. Choyke
  • Martin W. Brechbiel
Research Article

DOI: 10.1007/s11307-010-0424-8

Cite this article as:
Bumb, A., Regino, C.A.S., Egen, J.G. et al. Mol Imaging Biol (2011) 13: 1163. doi:10.1007/s11307-010-0424-8

Abstract

Purpose

This study aims to develop and characterize the trafficking of a dual-modal agent that identifies primary draining or sentinel lymph node (LN).

Procedure

Herein, a dual-reporting silica-coated iron oxide nanoparticle (SCION) is developed. Nude mice were imaged by magnetic resonance (MR) and optical imaging and axillary LNs were harvested for histological analysis. Trafficking through lymphatics was observed with intravital and ex vivo confocal microscopy of popliteal LNs in B6-albino, CD11c-EYFP, and lys-EGFP transgenic mice.

Results

In vivo, SCION allows visualization of LNs. The particle’s size and surface functionality play a role in its passive migration from the intradermal injection site and its minimal uptake by CD11c+ dendritic cells and CD169+ and lys+ macrophages.

Conclusions

After injection, SCION passively migrates to LNs without macrophage uptake and then can be used to image LN(s) by MRI and fluorescence. Thus, SCION can potentially be developed for use in sentinel node resections or for intralymphatic drug delivery.

Key words

NanoparticleMolecular imagingMRIOptical imagingLymph nodeSuperparamagnetic iron oxide

Supplementary material

11307_2010_424_MOESM1_ESM.mpg (702 kb)
Video 1Flow through lymphatic vessel pre-, during, and immediately post-intradermal injection of SCION(AlexaFluor555). Immediate passive diffusion of agent into the exposed vessel leading from hind footpad to popliteal LN is observed in the CD11c-EYFP mouse. The imaged lymphatic vessel was on the upper flank of a blood vessel (black region). Emissions from tissue-resident CD11c+ dendritic cells (green) are overlaid with emissions of SCION(AlexaFluor555) (red). Images were collected every 10 s for 15 min and played at 5 frames/s. A shift in the image frame occurred at the time of injection into the footpad distal to the imaging site. (MPG 702 kb)
11307_2010_424_MOESM2_ESM.mpg (490 kb)
Video 2Flow through lymphatic vessel 24 h post-intradermal injection of SCION(AlexaFluor555). Punctate movement of SCION(AlexaFluor555) (red) is observed in the exposed vessel leading from hind footpad to popliteal LN in the CD11c-EYFP mouse. However, this cell-mediated migration from the injection site is not by CD11c+ dendritic cells (green), as the emissions do not co-localize. The dark region in the lower right corner of the video is a blood vessel. Images were collected every 10 s for 12 min and played at 5 frames/s. (MPG 490 kb)

Copyright information

© Academy of Molecular Imaging and Society for Molecular Imaging 2010

Authors and Affiliations

  • Ambika Bumb
    • 1
  • Celeste A. S. Regino
    • 2
  • Jackson G. Egen
    • 3
  • Marcelino Bernardo
    • 2
    • 4
  • Peter J. Dobson
    • 5
  • Ronald N. Germain
    • 3
  • Peter L. Choyke
    • 2
  • Martin W. Brechbiel
    • 1
    • 6
  1. 1.Radiation Oncology Branch, National Cancer InstituteNational Institutes of HealthBethesdaUSA
  2. 2.Molecular Imaging Program, National Cancer InstituteNational Institutes of HealthBethesdaUSA
  3. 3.Laboratory of Immunology, National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaUSA
  4. 4.SAIC-Frederick IncNCI-FrederickFrederickUSA
  5. 5.Oxford University Begbroke Science ParkOxonUK
  6. 6.Radioimmune & Inorganic Chemistry Section, Radiation Oncology Branch, NCINIHBethesdaUSA