title: Iron Oxide-labeled Collagen Scaffolds for Non-invasive MR Imaging in Tissue Engineering.
abstract: Non-invasive imaging holds significant potential for implementation in tissue engineering. It can e.g. be used to monitor the localization and function of tissue-engineered implants, as well as their resorption and remodelling. Thus far, however, the vast majority of efforts in this area of research have focused on the use of ultrasmall super-paramagnetic iron oxide (USPIO) nanoparticle-labeled cells, colonizing the scaffolds, to indirectly image the implant material. Reasoning that directly labeling scaffold materials might be more beneficial (enabling imaging also in case of non-cellularized implants), more informative (enabling the non-invasive visualization and quantification of scaffold degradation) and more easy to translate into the clinic (since cell-free materials are less complex from a regulatory point-of-view), we here prepared three different types of USPIO nanoparticles, and incorporated them both passively and actively (via chemical conjugation; during collagen crosslinking) into collagen-based scaffold materials. We furthermore optimized the amount of USPIO incorporated into the scaffolds, correlated the amount of entrapped USPIO with MR signal intensity, showed that the labeled scaffolds are highly biocompatible, demonstrated that scaffold degradation can be visualized using MRI and provided initial proof-of-principle for the in vivo visualization of the scaffolds. Consequently, USPIO-labeled scaffold materials seem to be highly suitable for image-guided tissue engineering applications.
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany).
authors.forename: Marianne E
authors.initials: ME
authors.lastname: Mertens
authors.affiliation: Matricel GmbH Kaiserstraße 100 52134 Herzogenrath (Germany).
authors.forename: Alina
authors.initials: A
authors.lastname: Hermann
authors.affiliation: Matricel GmbH Kaiserstraße 100 52134 Herzogenrath (Germany).
authors.forename: Anne
authors.initials: A
authors.lastname: Bühren
authors.affiliation: Matricel GmbH Kaiserstraße 100 52134 Herzogenrath (Germany).
authors.forename: Leon
authors.initials: L
authors.lastname: Olde-Damink
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany).
authors.forename: Diana
authors.initials: D
authors.lastname: Möckel
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany).
authors.forename: Felix
authors.initials: F
authors.lastname: Gremse
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany).
authors.forename: Josef
authors.initials: J
authors.lastname: Ehling
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany).
authors.forename: Fabian
authors.initials: F
authors.lastname: Kiessling
authors.affiliation: Department for Experimental Molecular Imaging University Clinic and Helmholtz Institute for Biomedical Engineering RWTH - Aachen University Pauwelsstrasse 20, 52074 Aachen (Germany); Department of Controlled Drug Delivery MIRA Institute for Biomedical Engineering and Technical Medicine University of Twente PO Box 217, 7500 AE Enschede (The Netherlands).
authors.forename: Twan
authors.initials: T
authors.lastname: Lammers
keywords: Collagen Scaffolds; Imaging; Iron oxide nanoparticles; MRI; Tissue Engineering