Labeling stem cells with fluorescent dyes for non-invasive detection with optical imaging. Academic Article uri icon



  • Optical imaging (OI) is an easy, fast and inexpensive tool for in vivo monitoring of new stem cell based therapies. The technique is based on ex vivo labeling of stem cells with a fluorescent dye, subsequent intravenous injection of the labeled cells and visualization of their accumulation in specific target organs or pathologies. The presented technique demonstrates how we label human mesenchymal stem cells (hMSC) by simple incubation with the lipophilic fluorescent dye DiD (C67H103CIN2O3S) and how we label human embryonic stem cells (hESC) with the FDA approved fluorescent dye Indocyanine Green (ICG). The uptake mechanism is via adherence and diffusion of the lypophilic dye across the phospholipid cell membrane bilayer. The labeling efficiency is usually improved if the cells are incubated with the dye in serum-free media as opposed to incubation in serum-containing media. Furthermore, the addition of the transfection agent Protamine Sulfate significantly improves contrast agent uptake.

publication date

  • April 2, 2008



  • Fluorescent Dyes
  • Mesenchymal Stem Cells


PubMed Central ID

  • PMC2582850

Scopus Document Identifier

  • 80055113528

Digital Object Identifier (DOI)

  • 10.3791/686

PubMed ID

  • 19066580

Additional Document Info


  • 14