Magnetic Resonance Imaging for tracking cellular patterns obtained by Laser-Assisted Bioprinting

Abstract

Recent advances in the field of Tissue Engineering allowed to control the three-dimensional organization of engineered constructs. Cell pattern imaging and in vivo follow-up remain a major hurdle in in situ bioprinting onto deep tissues. Magnetic Resonance Imaging (MRI) associated with Micron-sized superParamagnetic Iron Oxide (MPIO) particles constitutes a non-invasive method for tracking cells in vivo. To date, no studies have utilized Cellular MRI as a tool to follow cell patterns obtained via bioprinting technologies. Laser-Assisted Bioprinting (LAB) has been increasingly recognized as a new and exciting addition to the bioprinting’s arsenal, due to its rapidity, precision and ability to print viable cells. This non-contact technology has been successfully used in recent in vivo applications. The aim of this study was to assess the methodology of tracking MPIO-labeled stem cells using MRI after organizing them by Laser-Assisted Bioprinting. Optimal MPIO concentrations for tracking bioprinted cells were determined. Accuracy of printed patterns was compared using MRI and confocal microscopy. Cell densities within the patterns and MRI signals were correlated. MRI enabled to detect cell patterns after in situ bioprinting onto a mouse calvarial defect. Results demonstrate that MRI combined with MPIO cell labeling is a valuable technique to track bioprinted cells in vitro and in animal models.

Iron Oxide Nanoparticles in Regenerative Medicine and Tissue Engineering

“…For example, Kérourédan et al used a laser-assisted in situ bioprinting method to print viable human stem cells from apical papilla onto a mouse calvarial defect. Printed patterns of cells with superparamagnetic microspheres demonstrated the feasibility of noninvasive cell tracking by MRI [ 316 ].…”

Recent Advancement in Biological Sciences

“…These imaging modalities using X ray beam can generate closely spaced axial slices of tissue design, which after surface rendering and stereolithographic editing, can totally describe whole volume of the target tissue. MRI using Nuclear Magnetic Resonance (NMR) (Kérourédan et al, 2018), can also give high contrast spatial resolution in case of soft tissues without exposure to harmful radiations. The colour contrast of biological structures in this process however can be raised with intelligently utilizing some contrast reagents.…”

In Vivo Tracking of Tissue Engineered Constructs

“…Recent advances in contrast agent design and development have made it possible to detect and track cell populations within the complex tissue-engineered constructs both in vitro and post implantation in vivo. These in vivo MRI cell-tracking processes can be performed using a variety of contrast agents, such as gadolinium, fluorine, or manganese, as well as superparamagnetic nanoparticles [20,21]. These materials are the preferred MRI contrast agents for TE applications as they are usually less cytotoxic and offer more reliable cellular uptake for imaging.…”