Biological Characteristics of Fluorescent Superparamagnetic Iron Oxide Labeled Human Dental Pulp Stem Cells

Abstract

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we investigate the effects of fluorescent superparamagnetic iron oxide particles (SPIO) (Molday ION Rhodamine-B™, MIRB) on biological properties of human dental pulp stem cells (hDPSCs) and monitor hDPSCs in vitro and in vivo using magnetic resonance imaging (MRI). Morphological analysis showed that intracellular MIRB particles were distributed in the cytoplasm surrounding the nuclei of hDPSCs. 12.5–100 μg/mL MIRB all resulted in 100% labeling efficiency. MTT showed that 12.5–50 μg/mL MIRB could promote cell proliferation and MIRB over 100 μg/mL exhibited toxic effect on hDPSCs. In vitro MRI showed that 1 × 106 cells labeled with various concentrations of MIRB (12.5–100 μg/mL) could be visualized. In vivo MRI showed that transplanted cells could be clearly visualized up to 60 days after transplantation. These results suggest that 12.5–50 μg/mL MIRB is a safe range for labeling hDPSCs. MIRB labeled hDPSCs cell can be visualized by MRI in vitro and in vivo. These data demonstrate that MIRB is a promising candidate for hDPSCs tracking in hDPSCs based dental pulp regeneration therapy.

SHED Cells Labeled with MIRB can be Tracked in Repairing Periodontal Bone Defects in Rats

“…In the current study, various concentrations of 12.5, 25, 50 and 100 µg Fe/ml were used to incubate with SHED cells to determine the proper labeling concentration. Our results showed that the viability and proliferation of the cells were both affected by the concentration of 100 µg Fe/ml which is consistent with previous reports [31].…”

“…Many different types of cells have been labeled with MIRB successfully. The proliferation, phenotype, and differentiation of cells have been investigated after labeling [23][24][25]. However, little knowledge is known about the biological in uences of MIRB on SHED cells.…”

Triple-modal imaging of stem-cells labeled with multimodal nanoparticles, applied in a stroke model

“…Dual-image modalities are often used in in vivo studies for homing and tracking evaluations under different approaches[10,26,27]. However, triple-image modality analyses, such as the analysis performed in this study, are currently scarce in the literature, and such analyses require multimodal nanoparticles.…”

“…The same nanoparticle composition, with the exception of the type of fluorophore (rhodamine), resulted in little difference in cellular viability when assessed in the same range of nanoparticle concentrations (100% to 95%) using the MTT assay. However, a significantly high apoptosis rate was found in 100 µg Fe/mL (78% viability) in comparison to unlabeled cells, due to the toxic effect of a high concentration on stem cell viability[26,27,44]. A study by Addicott (2010) also showed that these nanoparticles maintained the immunophenotypic profile, even after labeling of hBM-MSCs[44].…”

“…The correlation of the load quantification results based on images and spectrum techniques applied in our study in vitro (MRI, NIRF and ICP-MS) helped to improve the precision of these data and to understand the variation between the measurements according to the tested nanoparticle concentrations. Studies on multifunctional nanoparticles involving evaluations via multimodal images often show image analyses in a qualitative manner[26,27]. However, other studies either complement qualitative image analyses with techniques that permit nanoparticle quantification with more precision, such as inductively coupled plasma spectrometry[47,48], or use different approaches to quantify the nanoparticle load in cells by using image analysis[10,14,16].…”