title: Assessment of local reaction to vaccines in live piglets with magnetic resonance imaging compared to histopathology.
abstract: The safety of veterinary vaccines is assessed in clinical trials in Europe. The assessment of the local tissue reaction to vaccination by magnetic resonance imaging (MRI) could reduce the number of animals needed because repeated examinations can be performed in the same animal over time. The present study compared the evaluation of local tissue reactions to vaccination using MRI in live pigs with histopathology of porcine tissue, the current gold standard in regulatory safety testing. Eight piglets each were administered one of two commercial vaccines into marked injection sites. All animals were sedated and scanned repeatedly by MRI using a contrast agent up to day 29 after vaccination. On day 29, the animals were euthanized and underwent a pathological examination. The MRI results were compared with the pathomorphological findings at the injection site by regression analysis. The MR images and the pathological examinations yielded matching results concerning the sizes of the affected tissue volumes or areas. The use of MRI for regulatory safety testing can reduce the number of animals needed to 8 per examination group. The volume of a local reaction and its progression over time can be evaluated and documented. If persistent lesions develop a final pathomorphological examination is needed to identify the kind and local distribution of the reaction.
authors.affiliation: Livestock Center Oberschleissheim, Veterinary Faculty of the Ludwig-Maximilians-University Munich, Oberschleissheim, Germany.
authors.forename: Maren
authors.initials: M
authors.lastname: Bernau
authors.affiliation: Livestock Center Oberschleissheim, Veterinary Faculty of the Ludwig-Maximilians-University Munich, Oberschleissheim, Germany.|University of Applied Sciences Weihenstephan-Triesdorf, Weidenbach, Germany.
authors.forename: Prisca V
authors.initials: PV
authors.lastname: Kremer
authors.affiliation: Livestock Center Oberschleissheim, Veterinary Faculty of the Ludwig-Maximilians-University Munich, Oberschleissheim, Germany.
authors.forename: Lena S
authors.initials: LS
authors.lastname: Kreuzer
authors.affiliation: Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Emrich
authors.affiliation: Livestock Center Oberschleissheim, Veterinary Faculty of the Ludwig-Maximilians-University Munich, Oberschleissheim, Germany.
authors.forename: Elke
authors.initials: E
authors.lastname: Pappenberger
authors.affiliation: Paul-Ehrlich-Institut, Langen, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Cussler
authors.affiliation: Paul-Ehrlich-Institut, Langen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Hoffmann
authors.affiliation: Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Leipig
authors.affiliation: Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University Munich, Munich, Germany.
authors.forename: Walter
authors.initials: W
authors.lastname: Hermanns
authors.affiliation: Livestock Center Oberschleissheim, Veterinary Faculty of the Ludwig-Maximilians-University Munich, Oberschleissheim, Germany.
authors.forename: Armin Manfred
authors.initials: AM
authors.lastname: Scholz
mesh_terms: D000826:Animal Testing Alternatives; D000818:Animals; D005260:Female; D006653:Histology; D008279:Magnetic Resonance Imaging / Q000662:veterinary*; D008297:Male; D023421:Models, Animal; D010336:Pathology; D012449:Safety; D013552:Swine / Q000276:immunology*; D014611:Vaccination / Q000662:veterinary; D014612:Vaccines / Q000009:adverse effects* / Q000276:immunology
chemical_list: D014612:Vaccines
keywords: local reaction; magnetic resonance imaging; pathomorphological examination; pig; safety testing