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Labeling of mesenchymal stem cells for MRI with single-cell sensitivity.

Ariza de Schellenberger A, Kratz H, Farr TD, Löwa N, Hauptmann R, Wagner S, Taupitz M, Schnorr J, Schellenberger EA - Int J Nanomedicine (2016)

Bottom Line: Attempts should be made to achieve better cell separation for homogeneous NP loading and to thus improve NP-uptake-dependent biocompatibility studies and cell detection by MRI and future MPI.Additionally, using a 7 T MR imager equipped with a cryocoil resulted in approximately two times higher detection.In conclusion, we established labeling conditions for new high-relaxivity MCP, VSOP, and Resovist(®) for improved MRI of MSC with single-cell sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Center for Stroke Research Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany.

ABSTRACT
Sensitive cell detection by magnetic resonance imaging (MRI) is an important tool for the development of cell therapies. However, clinically approved contrast agents that allow single-cell detection are currently not available. Therefore, we compared very small iron oxide nanoparticles (VSOP) and new multicore carboxymethyl dextran-coated iron oxide nanoparticles (multicore particles, MCP) designed by our department for magnetic particle imaging (MPI) with discontinued Resovist(®) regarding their suitability for detection of single mesenchymal stem cells (MSC) by MRI. We achieved an average intracellular nanoparticle (NP) load of >10 pg Fe per cell without the use of transfection agents. NP loading did not lead to significantly different results in proliferation, colony formation, and multilineage in vitro differentiation assays in comparison to controls. MRI allowed single-cell detection using VSOP, MCP, and Resovist(®) in conjunction with high-resolution T2*-weighted imaging at 7 T with postprocessing of phase images in agarose cell phantoms and in vivo after delivery of 2,000 NP-labeled MSC into mouse brains via the left carotid artery. With optimized labeling conditions, a detection rate of ~45% was achieved; however, the experiments were limited by nonhomogeneous NP loading of the MSC population. Attempts should be made to achieve better cell separation for homogeneous NP loading and to thus improve NP-uptake-dependent biocompatibility studies and cell detection by MRI and future MPI. Additionally, using a 7 T MR imager equipped with a cryocoil resulted in approximately two times higher detection. In conclusion, we established labeling conditions for new high-relaxivity MCP, VSOP, and Resovist(®) for improved MRI of MSC with single-cell sensitivity.

No MeSH data available.


Related in: MedlinePlus

MRI detection at 7 T of mesenchymal stem cells in mouse brain after carotid injection of 2,000 NP-labeled cells.Notes: Improved visualization of magnetic field microdistortions in phase images (lower row) vs magnitude images (upper row) is observed for all NP-labeled MSC. Single microdistortions correspond to MSC labeled with Resovist® (A), MCP (B), and VSOP (C). Cells are visualized in the left hemisphere (supine position), while the right side is mostly free of cells and served as background control. Superparamagnetic iron quantification by MPS (D) confirmed that MRI signal was specific to NPs in the left hemisphere of mice injected with Resovist®-labeled (6.5 ng) and MCP-labeled MSC (13.1 ng), while corresponding right hemispheres had no signal for NPs, and total NP amount in brain (C) was too small to be detected (out of range).Abbreviations: MCP, multicore carboxy-methyl-dextran-coated iron oxide nanoparticle; MPS, magnetic particle spectroscopy; OR, out of range; NP, nanoparticle; VSOP, very small iron oxide nanoparticle.
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f6-ijn-11-1517: MRI detection at 7 T of mesenchymal stem cells in mouse brain after carotid injection of 2,000 NP-labeled cells.Notes: Improved visualization of magnetic field microdistortions in phase images (lower row) vs magnitude images (upper row) is observed for all NP-labeled MSC. Single microdistortions correspond to MSC labeled with Resovist® (A), MCP (B), and VSOP (C). Cells are visualized in the left hemisphere (supine position), while the right side is mostly free of cells and served as background control. Superparamagnetic iron quantification by MPS (D) confirmed that MRI signal was specific to NPs in the left hemisphere of mice injected with Resovist®-labeled (6.5 ng) and MCP-labeled MSC (13.1 ng), while corresponding right hemispheres had no signal for NPs, and total NP amount in brain (C) was too small to be detected (out of range).Abbreviations: MCP, multicore carboxy-methyl-dextran-coated iron oxide nanoparticle; MPS, magnetic particle spectroscopy; OR, out of range; NP, nanoparticle; VSOP, very small iron oxide nanoparticle.

Mentions: MRI single-cell detection of MSC labeled with Resovist®, MCP, and VSOP was performed on murine brains after delivery of only 2,000 cells into the CA (Figure 6) and 1,000 cells for MCP-labeled MSC (Figure S3). The high-resolution T2*-weighted FLASH sequences, as described in the “Methods” section, allowed detection of MFMDs caused by labeled MSC immediately after cell injection for all tested NPs, as shown in Figure 6 (total scanning time: 20 minutes).


Labeling of mesenchymal stem cells for MRI with single-cell sensitivity.

Ariza de Schellenberger A, Kratz H, Farr TD, Löwa N, Hauptmann R, Wagner S, Taupitz M, Schnorr J, Schellenberger EA - Int J Nanomedicine (2016)

MRI detection at 7 T of mesenchymal stem cells in mouse brain after carotid injection of 2,000 NP-labeled cells.Notes: Improved visualization of magnetic field microdistortions in phase images (lower row) vs magnitude images (upper row) is observed for all NP-labeled MSC. Single microdistortions correspond to MSC labeled with Resovist® (A), MCP (B), and VSOP (C). Cells are visualized in the left hemisphere (supine position), while the right side is mostly free of cells and served as background control. Superparamagnetic iron quantification by MPS (D) confirmed that MRI signal was specific to NPs in the left hemisphere of mice injected with Resovist®-labeled (6.5 ng) and MCP-labeled MSC (13.1 ng), while corresponding right hemispheres had no signal for NPs, and total NP amount in brain (C) was too small to be detected (out of range).Abbreviations: MCP, multicore carboxy-methyl-dextran-coated iron oxide nanoparticle; MPS, magnetic particle spectroscopy; OR, out of range; NP, nanoparticle; VSOP, very small iron oxide nanoparticle.
© Copyright Policy
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4835118&req=5

f6-ijn-11-1517: MRI detection at 7 T of mesenchymal stem cells in mouse brain after carotid injection of 2,000 NP-labeled cells.Notes: Improved visualization of magnetic field microdistortions in phase images (lower row) vs magnitude images (upper row) is observed for all NP-labeled MSC. Single microdistortions correspond to MSC labeled with Resovist® (A), MCP (B), and VSOP (C). Cells are visualized in the left hemisphere (supine position), while the right side is mostly free of cells and served as background control. Superparamagnetic iron quantification by MPS (D) confirmed that MRI signal was specific to NPs in the left hemisphere of mice injected with Resovist®-labeled (6.5 ng) and MCP-labeled MSC (13.1 ng), while corresponding right hemispheres had no signal for NPs, and total NP amount in brain (C) was too small to be detected (out of range).Abbreviations: MCP, multicore carboxy-methyl-dextran-coated iron oxide nanoparticle; MPS, magnetic particle spectroscopy; OR, out of range; NP, nanoparticle; VSOP, very small iron oxide nanoparticle.
Mentions: MRI single-cell detection of MSC labeled with Resovist®, MCP, and VSOP was performed on murine brains after delivery of only 2,000 cells into the CA (Figure 6) and 1,000 cells for MCP-labeled MSC (Figure S3). The high-resolution T2*-weighted FLASH sequences, as described in the “Methods” section, allowed detection of MFMDs caused by labeled MSC immediately after cell injection for all tested NPs, as shown in Figure 6 (total scanning time: 20 minutes).

Bottom Line: Attempts should be made to achieve better cell separation for homogeneous NP loading and to thus improve NP-uptake-dependent biocompatibility studies and cell detection by MRI and future MPI.Additionally, using a 7 T MR imager equipped with a cryocoil resulted in approximately two times higher detection.In conclusion, we established labeling conditions for new high-relaxivity MCP, VSOP, and Resovist(®) for improved MRI of MSC with single-cell sensitivity.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Center for Stroke Research Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany.

ABSTRACT
Sensitive cell detection by magnetic resonance imaging (MRI) is an important tool for the development of cell therapies. However, clinically approved contrast agents that allow single-cell detection are currently not available. Therefore, we compared very small iron oxide nanoparticles (VSOP) and new multicore carboxymethyl dextran-coated iron oxide nanoparticles (multicore particles, MCP) designed by our department for magnetic particle imaging (MPI) with discontinued Resovist(®) regarding their suitability for detection of single mesenchymal stem cells (MSC) by MRI. We achieved an average intracellular nanoparticle (NP) load of >10 pg Fe per cell without the use of transfection agents. NP loading did not lead to significantly different results in proliferation, colony formation, and multilineage in vitro differentiation assays in comparison to controls. MRI allowed single-cell detection using VSOP, MCP, and Resovist(®) in conjunction with high-resolution T2*-weighted imaging at 7 T with postprocessing of phase images in agarose cell phantoms and in vivo after delivery of 2,000 NP-labeled MSC into mouse brains via the left carotid artery. With optimized labeling conditions, a detection rate of ~45% was achieved; however, the experiments were limited by nonhomogeneous NP loading of the MSC population. Attempts should be made to achieve better cell separation for homogeneous NP loading and to thus improve NP-uptake-dependent biocompatibility studies and cell detection by MRI and future MPI. Additionally, using a 7 T MR imager equipped with a cryocoil resulted in approximately two times higher detection. In conclusion, we established labeling conditions for new high-relaxivity MCP, VSOP, and Resovist(®) for improved MRI of MSC with single-cell sensitivity.

No MeSH data available.


Related in: MedlinePlus