Gadolinium-fullerenol as a paramagnetic contrast agent for cellular imaging

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Cell Biology

Background:

• Magnetic resonance imaging (MRI) is crucial for non-invasive cell tracking.
• Developing effective intracellular cell labeling agents is essential for enhancing MRI sensitivity.
• Gadolinium-based contrast agents offer paramagnetic properties for MRI signal enhancement.

Purpose of the Study:

• To evaluate Gd@C82 fullerenol for intracellular cell labeling and T1 enhancement in MRI.
• To assess the impact of Gd@C82 labeling on cell viability, metabolism, and differentiation.
• To determine the feasibility of using Gd@C82 for tracking cells using MRI.

Main Methods:

• Cells were labeled with Gd@C82 fullerenol using a transfection agent (protamine sulfate).
• Cell viability, proliferation, and differentiation assays were performed on mesenchymal stem cells (MSCs).
• Light and electron microscopy were used to visualize labeled cells; MRI was conducted in vitro and in vivo.

Main Results:

• Protamine sulfate enhanced Gd@C82 fullerenol uptake by cells.
• Electron microscopy confirmed endosomal localization of the label within the cytoplasm.
• Labeled cells, including MSCs, exhibited high viability and normal differentiation capacity.
• T1 relaxation time of labeled MSCs was significantly reduced (71% at 7 T) compared to unlabeled cells.

Conclusions:

• Intracellular cell labeling with Gd@C82 fullerenol is achievable, leading to T1-enhanced MRI.
• Gd@C82 labeling does not compromise cell viability or differentiation potential.
• Gd fullerenols represent a promising class of agents for future cell tracking and in vivo imaging applications.