Figure 2. Acoustically targeted chemogenetics (ATAC).

A) ATAC combines FUS-BBBO, viral vector gene delivery, and chemogenetics to achieve fully noninvasive spatially, genetically, and temporally specific control cells in the brain. B) In ATAC process MRI-guided focused ultrasound reversibly opens the BBB to deliver viral vectors carrying chemogenetic receptors that can be activated specifically by a BBB-permeable ligand. (C) Safe and noninvasive opening of the BBB with FUS in hippocampus which was used to deliver viral vectors carrying DNA with a cell specific promoter and a chemogenetic receptor. BBB opening is visualized by extravasation of gadolinium contrast agent in a T₁-weighted MRI. (D) Gene expression of engineered chemogenetic receptors that respond to a specific BBB-permeable drug, as visualized by immunostaining (red). (E) The expression of engineered receptors allows subsequent pharmacological control of specific neurons and resulting behavior, such as memory recall. Adapted with permission from ref. ²⁸. Copyright (2018) Nature-Springer.