A method of increasing blood-brain barrier permeability of selected brain tissue in a subject in need thereof is carried out by: (a) parenterally administering to the subject stem cells that migrate to the brain tissue, the stem cells containing a recombinant nucleic acid, the recombinant nucleic acid comprising a nucleic acid encoding a barrier-opening protein or peptide operably associated with a heat-inducible promoter； and then (b) selectively heating the selected brain tissue sufficient to induce the expression of the barrier-opening protein or peptide in an amount effective to increase the permeability of the blood-brain barrier in the selected brain tissue. Nucleic acids, vectors, stem cells and compositions useful for carrying out such methods are also described.
