Although our results show that these sTDEVs do not increase in vivo permeability of the BBB under our experimental conditions, these post-H-FIRE sTDEVs are retained in the brain, exhibit cerebral endothelial cell tropism, and correlate with increased infiltration of Iba1+ cells; thus, future investigations are warranted to determine the timescale of this retention and their furthered roles in the brain microenvironment after H-FIRE ablation of brain tumors. The gene discussed is AIF1; the disease is brain neoplasm.