MRI method for labeling and imaging decellularized extracellular matrix scaffolds for tissue engineering.

Area of Science:

• Biomaterials Science
• Medical Imaging
• Tissue Engineering

Background:

• Decellularized extracellular matrix (dECM) is a promising biomaterial for tissue regeneration.
• Visualizing and monitoring dECM scaffolds in vivo remains a challenge for optimizing tissue engineering strategies.

Purpose of the Study:

• To develop a facile method for labeling and imaging decellularized extracellular matrix (dECM) scaffolds.
• To assess the feasibility of using a novel manganese porphyrin (MnPNH2) for dECM labeling and MRI visualization.

Main Methods:

• Synthesis of a manganese porphyrin (MnPNH2) for dECM labeling.
• Optimization of the labeling protocol on various dECM scaffolds (porcine bladder, trachea, murine lungs).
• Assessment of MRI signal changes (T1 and T2 relaxation times) and in vivo MRI detection.
• Evaluation of MnPNH2 toxicity on human umbilical vein endothelial cells.
• Analysis of MnPNH2 incorporation, retention, and long-term stability within dECM.

Main Results:

• Uniform labeling of dECM scaffolds, including thick 3D organs, with high MRI signal-to-noise ratio.
• Significant T1 reduction (nearly 10-fold) achieved at 0.4 mM MnPNH2, with sufficient contrast at 0.2 mM.
• No observed toxicity up to the maximum tested concentration (0.4 mM).
• Long-term retention of MnPNH2 in dECM, with less than 20% loss over 30 days.

Conclusions:

• This study presents the first MRI-based method for visualizing dECM scaffolds.
• The developed labeling technique offers potential for long-term monitoring and optimization of dECM-based organ tissue engineering.
• MnPNH2 is a safe and effective agent for labeling dECM, facilitating advanced imaging in regenerative medicine.