Conclusions
Increasing evidences prove that UTMD is a promising strategy to improve delivery efficiency, thus emerges as a method with great promise for target-specific gene delivery. A variety of experiments have demonstrated that the combination of UTMD and viral and non-viral vectors in gene delivery could not only enhance the efficiency of the viral vector, but also avoid its immunogenicity. Thus it may become a feasible, novel candidate for gene therapy, providing support to gene therapy trial for patients with cardiovascular diseases.
UTMD is a promising technique for gene delivery, but most of its studies are in the preclinical stage. UTMD still remains limited by its safety and efficiency. Future work needs to be done before its clinical application, including optimization of microbubble preparation technology to efficiently carry gene payloads while maintaining acoustic activity, prolonging circulation time to prevent clearance by the mononuclear cell, improving targeting techniques to enhance tissue binding force in areas of high shear stress, and illustration of optimal ultrasound parameters for each microbubble and its intended application. What is more important, as UTMD mediated gene therapy involve the multiple interacting modalities, there needs to be close collaboration between chemists, ultrasound engineers, and biologists to move this strategy to fruition.