Gd-loaded-RBCs for the assessment of tumor vascular volume by contrast-enhanced-MRI.
The assessment of the fractional vascular volume (vV) in the tumor area is of great interest in the characterization of tumor and it can be useful to monitor the outcome of anti-angiogenetic therapies. The high spatial and temporal resolution of Magnetic Resonance Imaging makes it the election imaging modality to monitor in vivo the vascular volume changes. Commonly used MRI methods to obtain this information rely on the administration of contrast agents that modify the bulk water relaxation times but, unfortunately, they can provide only an estimate of vV since they are not fully retained in the vascular space. Herein, Gd-loaded Red Blood Cells (Gd-RBCs) are proposed as a contrast agent able to provide quantitative information on tumor vascularization. Being Gd-RBCs fully retained in the vascular space, the proposed method does not suffer for the limitations associated to the use of extracellular Gd-agents that quickly extravasate in the leaky tumor vasculature. Furthermore, the long half-life and biocompatibility of Gd-RBCs allows repeating the measurement many times upon their administration; this ensures the possibility to in vivo evaluate the change of vascular volume during tumor growth. For these reasons, Gd-RBCs may represent a highly biocompatible imaging reporter of vasculature, able to quantitatively assess changes in the vascular volume in the ROI.
Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino (IT), Italy.
Giuseppe
G
Ferrauto
Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino (IT), Italy.
Enza
E
Di Gregorio
Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino (IT), Italy.
Walter
W
Dastrù
Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino (IT), Italy.
Stefania
S
Lanzardo
Department of Molecular Biotechnologies and Health Sciences, University of Torino, Torino (IT), Italy; IBB-CNR-UOS at The University of Torino (IT), Italy. Electronic address: silvio.aime@unito.it.
Silvio
S
Aime
D000818:Animals; D001672:Biocompatible Materials; D001921:Brain / Q000473:pathology; D003287:Contrast Media / Q000737:chemistry*; D004912:Erythrocytes / Q000187:drug effects*; D005260:Female; D005682:Gadolinium / Q000737:chemistry*; D008279:Magnetic Resonance Imaging; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D009132:Muscles / Q000473:pathology; D009369:Neoplasms / Q000098:blood supply*; D009389:Neovascularization, Pathologic; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D047368:Tumor Burden
D001672:Biocompatible Materials; D003287:Contrast Media; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D005682:Gadolinium
Blood; Gadolinium complexes; Image analysis; Magnetic resonance imaging; Red blood cells; Vascular volume