title: MR imaging of murine arthritis using ultrasmall superparamagnetic iron oxide particles.
abstract: The objective of this work was to determine the ability of magnetic resonance (MR) imaging with ultrasmall superparamagnetic iron oxide (USPIO) particles to provide quantitative measures of inflammation in autoimmune arthritis. Mice were injected intravenously or intra-articularly with USPIO followed by magnetic resonance and histological assessment of the knee joint. Comparisons were made between MR microimages and histology in naïve mice and mice with collagen-induced arthritis.Following intravenous administration, accumulation of USPIO was observed in the popliteal lymph nodes, but not the joint. Administration of USPIO intra-articularly resulted in signal loss in the joint. The MR signal intensity could be quantified and correlated with iron staining in the synovial lining. A marked increase in USPIO uptake and a corresponding decrease in signal intensity were observed in arthritic, compared to naïve mice. Areas of focal signal loss corresponded to foci of iron staining by histology. These studies may provide a basis for the clinical application of USPIO in arthritis for assessing disease severity and monitoring response to therapy.
authors.affiliation: Department of Radiology, Imaging Research Center, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA. bjd@athena.chmcc.org
authors.forename: B J
authors.initials: BJ
authors.lastname: Dardzinski
authors.forename: V J
authors.initials: VJ
authors.lastname: Schmithorst
authors.forename: S K
authors.initials: SK
authors.lastname: Holland
authors.forename: G P
authors.initials: GP
authors.lastname: Boivin
authors.forename: T
authors.initials: T
authors.lastname: Imagawa
authors.forename: S
authors.initials: S
authors.lastname: Watanabe
authors.forename: J M
authors.initials: JM
authors.lastname: Lewis
authors.forename: R
authors.initials: R
authors.lastname: Hirsch
mesh_terms: D000818:Animals; D001170:Arthritis, Infectious / Q000175:diagnosis* / Q000473:pathology; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D003911:Dextrans; D052203:Ferrosoferric Oxide; D019786:Gadolinium DTPA; D007501:Iron; D007719:Knee Joint / Q000276:immunology / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D010087:Oxides; D012815:Signal Processing, Computer-Assisted
chemical_list: D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; D010087:Oxides; C097921:ferumoxtran-10; D007501:Iron; D019786:Gadolinium DTPA; D052203:Ferrosoferric Oxide