title: Paramagnetic liposomes as innovative contrast agents for magnetic resonance (MR) molecular imaging applications.
abstract: This article illustrates some innovative applications of liposomes loaded with paramagnetic lanthanide-based complexes in MR molecular imaging field. When a relatively high amount of a Gd(III) chelate is encapsulated in the vesicle, the nanosystem can simultaneously affect both the longitudinal (R(1)) and the transverse (R(2)) relaxation rate of the bulk H2O H-atoms, and this finding can be exploited to design improved thermosensitive liposomes whose MRI response is not longer dependent on the concentration of the probe. The observation that the liposome compartmentalization of a paramagnetic Ln(III) complex induce a significant R(2) enhancement, primarily caused by magnetic susceptibility effects, prompted us to test the potential of such agents in cell-targeting MR experiments. The results obtained indicated that these nanoprobes may have a great potential for the MR visualization of cellular targets (like the glutamine membrane transporters) overexpressing in tumor cells. Liposomes loaded with paramagnetic complexes acting as NMR shift reagents have been recently proposed as highly sensitive CEST MRI agents. The main peculiarity of CEST probes is to allow the MR visualization of different agents present in the same region of interest, and this article provides an illustrative example of the in vivo potential of liposome-based CEST agents.
authors.affiliation: Department of Chemistry IFM and Molecular Imaging Center, University of Torino, Via P. Giuria 7, I-10125, Torino (phone: +39-011-6706452; fax: +39-011-6706487).
authors.forename: Enzo
authors.initials: E
authors.lastname: Terreno
authors.affiliation: Department of Chemistry IFM and Molecular Imaging Center, University of Torino, Via P. Giuria 7, I-10125, Torino (phone: +39-011-6706452; fax: +39-011-6706487).
authors.forename: Daniela
authors.initials: D
authors.lastname: Delli Castelli
authors.affiliation: CRM Bracco Imaging S.p.A., c/o Bioindustry Park Canavese, Via Ribes 5, I-10010 Colleretto Giacosa (TO).
authors.forename: Claudia
authors.initials: C
authors.lastname: Cabella
authors.affiliation: Department of Chemistry IFM and Molecular Imaging Center, University of Torino, Via P. Giuria 7, I-10125, Torino (phone: +39-011-6706452; fax: +39-011-6706487).
authors.forename: Walter
authors.initials: W
authors.lastname: Dastrù
authors.affiliation: Department of Chemistry IFM and Molecular Imaging Center, University of Torino, Via P. Giuria 7, I-10125, Torino (phone: +39-011-6706452; fax: +39-011-6706487).
authors.forename: Alberto
authors.initials: A
authors.lastname: Sanino
authors.affiliation: CRM Bracco Imaging S.p.A., c/o Bioindustry Park Canavese, Via Ribes 5, I-10010 Colleretto Giacosa (TO).
authors.forename: Joseph
authors.initials: J
authors.lastname: Stancanello
authors.affiliation: Dipartimento di Scienze dell'Ambiente e della Vita, Università del Piemonte Orientale 'Amedeo Avogadro', Via Bellini 25/G, I-15100 Alessandria.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Tei
authors.affiliation: Department of Chemistry IFM and Molecular Imaging Center, University of Torino, Via P. Giuria 7, I-10125, Torino (phone: +39-011-6706452; fax: +39-011-6706487).
authors.forename: Silvio
authors.initials: S
authors.lastname: Aime
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D003287:Contrast Media / Q000737:chemistry* / Q000493:pharmacokinetics; D004355:Drug Stability; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D006801:Humans; D028581:Lanthanoid Series Elements / Q000737:chemistry / Q000493:pharmacokinetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008546:Melanoma, Experimental / Q000175:diagnosis; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D010743:Phospholipids / Q000737:chemistry; D012680:Sensitivity and Specificity; D013696:Temperature; D053835:Unilamellar Liposomes / Q000737:chemistry* / Q000493:pharmacokinetics
chemical_list: D003287:Contrast Media; D028581:Lanthanoid Series Elements; D010743:Phospholipids; D053835:Unilamellar Liposomes