FIG. 3.

Localization of the expressed hMCT8 protein in brains of Mct8KO mice given high doses of AAV9-ShMCT8 IV (4 × 10¹¹ vp/mouse) and ICV (3 × 10¹⁰ vp/mouse) compared with Wt and KO animals injected IV with EV. Representative images showing hMCT8 expression (in brown) detected with a specific antibody by immunohistochemistry counterstained with hematoxylin in the somatosensory region of the cerebral cortex (A, D, G, J), the cerebellar lobule 4 (B, E, H, K), and choroid plexus (C, F, I, L) of Wt (A–C) and Mct8KO (D–F) mice injected with EV. Mct8KO mice were injected with AAV9-ShMCT8 IV (G–I) or ICV (J–L). In accordance with results from Western blots, hMCT8 was present in larger quantities in the cerebral cortex of mice injected with the virus ICV (J) than IV (G). However, much of the immunoreactivity was present in aggregates (white arrowheads). Some Purkinje cells (white arrows) were observed in both IV- and ICV-injected cerebellum (H and K) with remarkable hMCT8 expression at the dendritic arborizations (black arrowheads). The control, Wt mice injected with EV, did not show the positive signal of dendritic arborizations (B). hMCT8 was abundantly present at the choroid plexus of IV-injected KO mice (I) and only spottily expressed in mice given the virus ICV (L). The scale bar for each brain region is in the lower right corner of the left photograph and equals 50 μm. Color images available online at www.liebertpub.com/thy