title: Magnetization transfer as a potential tool for the early detection of acute graft rejection after lung transplantation in mice.
abstract: To investigate the value of magnetization transfer (MT) measurements for assessment of acute rejection (AR) in a murine lung transplantation model.
  
  
  
  Thirty mice including 15 C57BL/10 mice serving as donors and 15 C57BL/6 mice as recipients were examined in this study. MT imaging datasets were acquired on a 4.7 Tesla small animal MR scanner using a three-dimensional zero echo time sequence with a Gaussian-shaped MT prepulse with 1000° or 3000° flip angle and systematic variation of off-resonance frequencies between 1000 and 15,000 Hz. After image acquisition, the images were qualitatively assessed, magnetization transfer ratio (MTR) values were calculated and lungs were taken for histologic examination including staining with hematoxylin/eosin, Masson's trichrome (collagen), and α-smooth muscle (fibroproliferative tissue) staining.
  
  
  
  Lung transplantation was successfully performed in all 15 mice. All animals showed AR characterized by the presence of interstitial mononuclear cell infiltrates. There were significant differences of MTR in lungs with and without AR (P = 0.007). With a flip angle of 1000°, the largest differences between the MTR of healthy lungs and lungs with AR were observed for an off-resonance frequency of 10,000 Hz (difference MTR 1.80%) and 15,000 Hz (1.91%) and with a flip angle of 3000° at off-resonance frequencies of 6000 Hz (1.37%) and 8000 Hz (1.70%).
  
  
  
  MT measurements may provide a tool for the quantitative assessment of AR. J. Magn. Reson. Imaging 2016;44:1091-1098.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Switzerland. david.kenkel@usz.ch.
authors.forename: David
authors.initials: D
authors.lastname: Kenkel
authors.affiliation: Division of Thoracic Surgery, University Hospital Zurich, Switzerland.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Yamada
authors.affiliation: Institute for Biomedical Engineering, ETH Zurich and University of Zurich, Gloriastrasse 35, CH-8092, Zurich, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Weiger
authors.affiliation: Division of Thoracic Surgery, University Hospital Zurich, Switzerland.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Jungraithmayr
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Switzerland.
authors.forename: Moritz C
authors.initials: MC
authors.lastname: Wurnig
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Boss
mesh_terms: D000208:Acute Disease; D000818:Animals; D042241:Early Diagnosis; D005240:Feasibility Studies; D006084:Graft Rejection / Q000000981:diagnostic imaging* / Q000209:etiology*; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D016040:Lung Transplantation / Q000009:adverse effects*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
keywords: acute rejection; graft dysfunction; magnetic resonance; magnetization transfer; transplant rejection; zero echo time