Magnetic resonance imaging tracking of human adipose derived stromal cells within three-dimensional scaffolds for bone tissue engineering

Abstract

For bone tissue engineering, human Adipose Derived Stem Cells (hADSCs) are proposed to be associated with a scaffold for promoting bone regeneration. After implantation, cellularised scaffolds require a non-invasive method for monitoring their fate in vivo. The purpose of this study was to use Magnetic Resonance Imaging (MRI)-based tracking of these cells, labelled with magnetic agents for in vivo longitudinal assessment. hADSCs were isolated from adipose tissue and labelled with USPIO-rhodamine (Ultrasmall SuperParamagnetic Iron Oxide). USPIO internalisation, absence of toxicity towards hADSCs, and osteogenic differentiation of the labelled cells were evaluated in standard culture conditions. Labelled cells were then seeded within a 3D porous polysaccharidebased scaffold and imaged in vitro using fl uorescence microscopy and MRI. Cellularised scaffolds were implanted subcutaneously in nude mice and MRI analyses were performed from 1 to 28 d after implantation. In vitro, no effect of USPIO labelling on cell viability and osteogenic differentiation was found. USPIO were efficiently internalised by hADSCs and generated a high T2* contrast. In vivo MRI revealed that hADSCs remain detectable until 28 d after implantation and could migrate from the scaffold and colonise the area around it. These data suggested that this scaffold might behave as a cell carrier capable of both holding a cell fraction and delivering cells to the site of implantation. In addition, the present fi ndings evidenced that MRI is a reliable technique to validate cell-seeding procedures in 3D porous scaffolds, and to assess the fate of hADSCs transplanted in vivo.

Bone tissue engineering by using a combination of polymer/Bioglass composites with human adipose-derived stem cells

“…Adipose tissue is an abundant source of mesenchymal stem cells, which have shown promise in the field of regenerative medicine (Hicok et al 2004;Lalande et al 2011;Parker and Katz 2006).…”

Imaging Strategies for Tissue Engineering Applications

“…Various cell types including astrocytes, 45 chondrocytes (Fig. 5B), 46 and mesenchymal stem cells 47,48 were successfully detected and their localization was visualized within scaffolds or in vivo using cell labeling with superparamagnetic iron oxide nanoparticles (SPIONs). Similarly, gadoliniumbased magnetic imaging contrast was applied to label endothelial progenitor cells and the labeled cells were intramuscularly injected and successfully tracked in the ischemic rat hindlimb.…”

Mesenchymal stem cell tracking in the intervertebral disc

“…The USPIONs were effectively internalized by the hADSC and demonstrated T2* signal change. Hypointense regions, representing labeled cells, were seen in vivo 28 d following implantation [96] . Further research is required to optimize SPIONs for cell tracking.…”

“…USPION have also been investigated recently. Coated with dextran and PEG and combined with protamine sulfate, USPIONs have been cultured with human Adipose Derived Stem Cells (hADSCs) within a three dimensional scaffold [96] . In vitro, no effect on cell viablilty or osteogenic differentiation was seen from cell from unlabeled cells on T1 weighted imaging [105] .…”