Whole-body tracking of single cells via positron emission tomography

Nat Biomed Eng. 2020 Aug;4(8):835-844. doi: 10.1038/s41551-020-0570-5. Epub 2020 Jun 15.


In vivo molecular imaging can measure the average kinetics and movement routes of injected cells through the body. However, owing to non-specific accumulation of the contrast agent and its efflux from the cells, most of these imaging methods inaccurately estimate the distribution of the cells. Here, we show that single human breast cancer cells loaded with mesoporous silica nanoparticles concentrating the 68Ga radioisotope and injected into immunodeficient mice can be tracked in real time from the pattern of annihilation photons detected using positron emission tomography, with respect to anatomical landmarks derived from X-ray computed tomography. The cells travelled at an average velocity of 50 mm s-1 and arrested in the lungs 2-3 s after tail-vein injection into the mice, which is consistent with the blood-flow rate. Single-cell tracking could be used to determine the kinetics of cell trafficking and arrest during the earliest phase of the metastatic cascade, the trafficking of immune cells during cancer immunotherapy and the distribution of cells after transplantation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Line
  • Cell Survival / drug effects
  • Cell Tracking / methods*
  • Contrast Media / chemistry
  • Contrast Media / pharmacology
  • Female
  • Gallium Radioisotopes / chemistry
  • Gallium Radioisotopes / pharmacology
  • Humans
  • Metal Nanoparticles / chemistry
  • Metal Nanoparticles / toxicity
  • Mice
  • Mice, Nude
  • Positron-Emission Tomography
  • Silicon Dioxide / chemistry
  • Silicon Dioxide / pharmacology
  • Whole Body Imaging


  • Contrast Media
  • Gallium Radioisotopes
  • Silicon Dioxide
  • Gallium-68