Endomicroscopy Will Track Injected Mesenchymal Stem Cells in Rat Colitis Models

Area of Science:

• Gastroenterology
• Cell Biology
• Medical Imaging

Background:

• Mesenchymal stem cells (MSCs) show promise for treating inflammatory bowel disease (IBD).
• Current methods to track MSCs in the intestinal mucosa are limited.
• Noninvasive in vivo tracking of MSCs is needed for clinical applications.

Purpose of the Study:

• To evaluate endomicroscopy as a tool for noninvasively tracking mesenchymal stem cells (MSCs) in the colonic mucosa in vivo.
• To compare endomicroscopy findings with established histological methods for cell detection.

Main Methods:

• Rat MSCs were fluorescently labeled and imaged ex vivo and in vivo using an endomicroscope (FIVE1 system).
• In vivo tracking of enhanced green fluorescent protein (eGFP)-labeled MSCs was performed.
• Results were validated using immunofluorescence, immunohistochemistry, and fluorescent in situ hybridization.

Main Results:

• Endomicroscopy clearly visualized labeled MSCs ex vivo and tracked eGFP-labeled MSCs in vivo.
• The technique successfully quantified transplanted MSCs homing to the colonic mucosa in various rat models (allograft, xenograft, hypoxia, immunosuppression).
• A trend of enhanced MSC homing to inflamed mucosa post-hypoxia was observed.

Conclusions:

• Endomicroscopy is a novel, noninvasive tool for tracking transplanted MSCs in the colonic mucosa.
• This clinical-available method provides cellular resolution for in vivo tracking.
• It holds potential for personalizing treatment regimens for IBD patients.