Comparative Analysis of Fluorescent Labeling Techniques for Tracking Canine Amniotic Stem Cells

Area of Science:

• Regenerative Medicine
• Stem Cell Biology
• Veterinary Science

Background:

• Amniotic mesenchymal stem cells (AmMSCs) are promising for regenerative medicine due to their accessibility and low immunogenicity.
• Tracking AmMSCs is crucial for validating their efficacy in therapeutic applications.
• Efficient and reliable fluorescence labeling is needed for large-scale use of AmMSCs.

Purpose of the Study:

• To evaluate and compare different fluorescence labeling methods for canine AmMSCs.
• To determine the most suitable tracer for tracking AmMSCs in domestic animal studies.
• To assess fluorophore positivity, intensity, and longevity in canine AmMSCs.

Main Methods:

• Canine AmMSCs were labeled using two commercial fluorophores (CellTrace CFSE and CellTracker Green CMFDA) and lentiviral transduction for green fluorescent protein (GFP) expression.
• Fluorescence detection, intensity, and cell positivity were analyzed over time using flow cytometry.
• Labeling persistence and handling characteristics were evaluated for each method.

Main Results:

• All labeling methods resulted in detectable fluorescence.
• Commercial fluorophores (CTrace, CTracker) showed earlier detection (6 hours) and high positivity (>70% at day 7), but decreased significantly by day 20.
• GFP expression had delayed detection (≥48 hours) but offered longer fluorescence persistence, though with observed variability between repetitions.

Conclusions:

• Commercial fluorophores provide rapid and consistent labeling for short-term tracking of canine AmMSCs.
• GFP expression offers prolonged cell tracking but requires optimization for consistency.
• These findings support non-genomic labeling strategies for canine AmMSC research in regenerative medicine.