NR AWPY
AU Vetrugno,V.; Carpinelli,G.; Santoro,F.; Canese,R.; Di Bari,M.; Sbriccoli,M.; Cardone,F.; Lu,M.; Pocchiari,M.; Podo,F.
TI Detection of early MRI signal alterations in TSE experimental models
QU International Conference - Prion 2006: Strategies, advances and trends towards protection of society - 3.10.-6.10.2006, Torino, Italy, Lingotto Conference Centre - Poster sessions DIA-59
PT Konferenz-Poster
AB Transmissible spongiform encephalopathies (TSE) or prion diseases are lethal neurological disorders of animals (e.g. scrapie) and humans (e.g. CJD). Neuropathological features of TSE are spongiform change, neuronal loss, gliosis and accumulation of abnormal isoform of prion protein (PrPTSE). Although according to the WHO criteria, magnetic resonance imaging (MRI) is not a criterion for the diagnosis of CJD, it is recognized as a useful noninvasive diagnostic marker. To date few MR studies were performed on animal TSE models, using conventional MRI techniques. The aim of this study was to investigate the potential role of MRI in early detection of TSE using different animal models. We infected hamsters intracerebrally (i.c.), intraperitoneally (i.p.) or orally with 263K scrapie strain and mice, i.p., with mouse adapted variant-CJD prions. MRI T2W images (TR/TE = 2500/60-70-90 ms) and diffusion-weighted (DW) images (b = 2136 s/mm2, TR/TE = 2000/50 ms) were carried out at 4.7 T (INOVA SIS 200/183 system, Varian, Palo Alto, USA). The MR signal was detected with a surface coil, volume coil for hamsters or a home-made headphone coil for mice. MRI analyses showed hyperintensity in T2W images of thalamic nuclei areas in hamster brains (i.e. at 70 days post infection (dpi), i.c.; at 100-130 dpi, i.p.; from 130 up to 150 dpi, oral) and hypointensities in DW images in medulla oblongata of i.p. injected hamsters at 100-130 dpi. In variant-CJD infected mice T2W images revealed hyperintensities also in cortex. In our different TSE animal models we detected MR signal alterations at both pre-symptomatic and symptomatic stages of the disease. In particular: the increase in T2W signal could be detected mainly in orally and i.p. infected animals within a time window starting at about two third of the incubation period; the decrease in DW signal in i.p. scrapie infected hamsters was in general agreement with histopatological findings on disease progression in this model. The direct relationship between MR signal changes and histopatological observations is still to be definitively elucidated.
AD Department of Cell Biology and Neurosciences, ISS, Rome, Italy. E-mail: vetrugno@iss.it
SP englisch
PO Italien