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Accelerated stem cell labeling with ferucarbotran and protamine.

Golovko DM, Henning T, Bauer JS, Settles M, Frenzel T, Mayerhofer A, Rummeny EJ, Daldrup-Link HE - Eur Radiol (2009)

Bottom Line: Electron microscopy confirmed intracellular iron oxide uptake in lysosomes.Relaxation times correlated with results from ICP-AES.Our results show internalization of ferucarbotran can be accelerated in MSCs with protamine, an approved heparin antagonist and potentially clinically applicable uptake-enhancing agent.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology & Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.

ABSTRACT

Objective: To develop and characterize a clinically applicable, fast and efficient method for stem cell labeling with ferucarbotran and protamine for depiction with clinical MRI.

Methods: The hydrodynamic diameter, zeta potential and relaxivities of ferucarbotran and varying concentrations of protamine were measured. Once the optimized ratio was found, human mesenchymal stem cells (MSCs) were labeled at varying incubation times (1-24 h). Viability was assessed via Trypan blue exclusion testing. 150,000 labeled cells in Ficoll solution were imaged with T1-, T2- and T2*-weighted sequences at 3 T, and relaxation rates were calculated.

Results: Varying the concentrations of protamine allows for easy modification of the physicochemical properties. Simple incubation with ferucarbotran alone resulted in efficient labeling after 24 h of incubation while assisted labeling with protamine resulted in similar results after only 1 h. Cell viability remained unaffected. R2 and R2* relaxation rates were drastically increased. Electron microscopy confirmed intracellular iron oxide uptake in lysosomes. Relaxation times correlated with results from ICP-AES.

Conclusion: Our results show internalization of ferucarbotran can be accelerated in MSCs with protamine, an approved heparin antagonist and potentially clinically applicable uptake-enhancing agent.

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R1, R2 and R2* relaxation rates of samples of 150,000 MSCs in 400 μl Ficoll labeled with ferucarbotran (solid block), ferucarbotran in 25% FCS (diamond) and ferucarbotran with protamine (solid triangle) at 3 T. The R2* rate 0.19 ms−1 corresponds to the lowest measurable TE time of 5.2 ms. Data points are mean relaxation rates of triplicate samples ± standard deviation
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Fig4: R1, R2 and R2* relaxation rates of samples of 150,000 MSCs in 400 μl Ficoll labeled with ferucarbotran (solid block), ferucarbotran in 25% FCS (diamond) and ferucarbotran with protamine (solid triangle) at 3 T. The R2* rate 0.19 ms−1 corresponds to the lowest measurable TE time of 5.2 ms. Data points are mean relaxation rates of triplicate samples ± standard deviation

Mentions: Simple incubation On qualitative T2-weighted images, contrast effect was visible after 6 or more h of incubation with ferucarbotran in DMEM and after 24 h of incubation with ferucarbotran in DMEM + 25% FCS (Fig. 3). Quantitatively, R1, R2 and R2* relaxation rates gradually increased with increasing incubation time (Fig. 4). The effect on relaxation rates was more pronounced with cells labeled with ferucarbotran in DMEM than with ferucarbotran in DMEM + 25% FCS.Fig. 3


Accelerated stem cell labeling with ferucarbotran and protamine.

Golovko DM, Henning T, Bauer JS, Settles M, Frenzel T, Mayerhofer A, Rummeny EJ, Daldrup-Link HE - Eur Radiol (2009)

R1, R2 and R2* relaxation rates of samples of 150,000 MSCs in 400 μl Ficoll labeled with ferucarbotran (solid block), ferucarbotran in 25% FCS (diamond) and ferucarbotran with protamine (solid triangle) at 3 T. The R2* rate 0.19 ms−1 corresponds to the lowest measurable TE time of 5.2 ms. Data points are mean relaxation rates of triplicate samples ± standard deviation
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2822227&req=5

Fig4: R1, R2 and R2* relaxation rates of samples of 150,000 MSCs in 400 μl Ficoll labeled with ferucarbotran (solid block), ferucarbotran in 25% FCS (diamond) and ferucarbotran with protamine (solid triangle) at 3 T. The R2* rate 0.19 ms−1 corresponds to the lowest measurable TE time of 5.2 ms. Data points are mean relaxation rates of triplicate samples ± standard deviation
Mentions: Simple incubation On qualitative T2-weighted images, contrast effect was visible after 6 or more h of incubation with ferucarbotran in DMEM and after 24 h of incubation with ferucarbotran in DMEM + 25% FCS (Fig. 3). Quantitatively, R1, R2 and R2* relaxation rates gradually increased with increasing incubation time (Fig. 4). The effect on relaxation rates was more pronounced with cells labeled with ferucarbotran in DMEM than with ferucarbotran in DMEM + 25% FCS.Fig. 3

Bottom Line: Electron microscopy confirmed intracellular iron oxide uptake in lysosomes.Relaxation times correlated with results from ICP-AES.Our results show internalization of ferucarbotran can be accelerated in MSCs with protamine, an approved heparin antagonist and potentially clinically applicable uptake-enhancing agent.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology & Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.

ABSTRACT

Objective: To develop and characterize a clinically applicable, fast and efficient method for stem cell labeling with ferucarbotran and protamine for depiction with clinical MRI.

Methods: The hydrodynamic diameter, zeta potential and relaxivities of ferucarbotran and varying concentrations of protamine were measured. Once the optimized ratio was found, human mesenchymal stem cells (MSCs) were labeled at varying incubation times (1-24 h). Viability was assessed via Trypan blue exclusion testing. 150,000 labeled cells in Ficoll solution were imaged with T1-, T2- and T2*-weighted sequences at 3 T, and relaxation rates were calculated.

Results: Varying the concentrations of protamine allows for easy modification of the physicochemical properties. Simple incubation with ferucarbotran alone resulted in efficient labeling after 24 h of incubation while assisted labeling with protamine resulted in similar results after only 1 h. Cell viability remained unaffected. R2 and R2* relaxation rates were drastically increased. Electron microscopy confirmed intracellular iron oxide uptake in lysosomes. Relaxation times correlated with results from ICP-AES.

Conclusion: Our results show internalization of ferucarbotran can be accelerated in MSCs with protamine, an approved heparin antagonist and potentially clinically applicable uptake-enhancing agent.

Show MeSH