Indirect Sensitive MR Detection of Aβ Plaques with USPIO in Alzheimer Transgenic Mice

Jean-Sebastien Raynaud¹, Gaelle Louin¹, Olivier Rousseaux¹, Isabelle Raynal¹, Claire Corot¹

The aim was to evaluate the potentiality of an USPIO to increase the sensitivity to indirectly detect, via microglial phagocytic activity, Ab plaques, in Alzheimer transgenic mice. P904-Rhodamine was iv administrated in trangenic mice. MRI was performed at 2.35T and 7T. Microglia (CD45), iron (Perl's), Ab (Congo Red) and Rhodamine were analyzed on histological slices. Post P904 injection, several susceptibility artefacts were observed as focal spots all over the mouse brain. Iron, microglia, amyloid plaques et fluorescence were colocalized. These results suggest that P904 could be a very sensitive tool for Alzheimer disease diagnostic and prognostic.