The transfer of V5-hTau46
protein is correlated to brain area connected to the IS (caudal part of the CA1 layer). (a) Dextran amines (10 kD) are anterograde tracers: they were injected into the rat brain (n = 3), and one week later, the animals were sacrificed and their brains were processed to reveal fluorescent axons efferent from the IS. Brains were virtually divided into five sections: bregma +5.20 to +1.40, bregma +1.20 to -1.40, bregma -1.80 to -4.30, bregma -4.52 to -6.04 and bregma -6.30 to -7.80. (b) LVs encoding V5-hTau46WT were bilaterally injected into the CA1 layer (IS; bregma -5.3) of rat brains (n = 3). Five months later, the animals were sacrificed, and the whole brain was processed for immunohistochemical analysis using a rabbit polyclonal anti-V5 antibody. The brains were virtually divided into five sections as in (a). The bar scale is indicated on the figure. The drawing showing the extension of WT V5-Tau protein transfer from the IS to extreme rostral and caudal positions is illustrated in the lower part of the figure. These data showed that V5-hTau46WT Tau is transported throughout the brain using neural networks. (c) The V5-immunoreactivity is summarized in a cartoon drawing of several coronal sections at different bregma coordinates. The different blue intensities (level 1 to 3) indicate the density of fibres and the red stars indicate the presence of V5-immunopositive cellular bodies indicating a trans-cellular transfer of V5-hTau46WT Tau.