nCP:Fe-A Biomineral Magnetic Nanocontrast Agent for Tracking Implanted Stem Cells in Brain Using MRI
Ida M Anna1, Binulal N Sathy1, Anusha Ashokan1
1Amrita Centre for Nanosciences and Molecular Medicine, Amrita Vishwa Vidyapeetham University, Kochi, Kerala 682041, India.
ACS Applied Bio Materials
|January 13, 2022
Summary
Iron-doped calcium phosphate nanoparticles (nCP:Fe) enable effective in vivo tracking of stem cells using MRI. These biocompatible nanoparticles allow visualization of cell migration and engraftment in the brain for up to 30 days.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Radiology
Background:
- Accurate tracking of transplanted stem cells is crucial for evaluating stem cell therapies.
- Magnetic Resonance Imaging (MRI) offers non-invasive in vivo monitoring capabilities.
- Development of effective contrast agents is essential for sensitive MRI-based cell tracking.
Purpose of the Study:
- To develop and evaluate iron-doped calcium phosphate nanoparticles (nCP:Fe) as a novel biomineral nanocontrast agent.
- To assess the biocompatibility and labeling efficiency of nCP:Fe for mesenchymal stem cells (MSCs).
- To demonstrate the utility of nCP:Fe for in vivo MRI tracking of stem cells in the brain.
Main Methods:
- Synthesis of ~100 nm iron-doped calcium phosphate nanoparticles (nCP:Fe) with 9.81 wt% Fe3+.
- In vitro labeling of MSCs with nCP:Fe, assessing biocompatibility and differentiation potential.
- In vitro MRI studies to evaluate contrast enhancement (T2 relaxation time).
- In vivo MRI tracking of labeled MSCs transplanted into rat brains, followed by ex vivo histological confirmation.
Main Results:
- High labeling efficiency (~87%) of MSCs with nCP:Fe achieved under optimized conditions without affecting neurogenic differentiation.
- Significant T2 shortening (195 to 89 ms) observed in labeled cells, providing dark contrast in MRI.
- Successful in vivo visualization of labeled cells in rat brains for up to 30 days post-transplantation.
- Demonstrated migration of labeled MSCs towards an LPS-induced inflammatory site in the brain, confirmed by ex vivo staining.
Conclusions:
- nCP:Fe nanoparticles are biocompatible and effective for labeling stem cells for MRI tracking.
- nCP:Fe serves as a promising MRI contrast agent for monitoring stem cell migration, biodistribution, and engraftment in vivo.
- This approach holds potential for advancing the assessment of stem cell therapeutics in neurological applications.
