Nano-bioengineering for Drug and Gene Delivery
By: Kyeil Joo
Optimal treatment by many drugs often requires maintenance of the drug level for a prolonged time in order to achieve the therapeutic goals. Nanoparticle-based drug delivery systems, which possess capability of modulating drug release profile and improving drug circulation, have been widely viewed as a new treatment option for many therapeutic drugs. Especially for cancer treatment, the ability of nanoparticles to accumulate in tumor microenvironment has resulted in development of various therapeutic nanoparticles for clinical use. Liposomes are one of most popular nanocarrier, however, inherent instability in the presence of serum components and limited drug loading have remained prohibitive obstacles in their utility for the delivery of anticancer agents. To overcome theses challenges, I have developed a novel nanotechnology platform (CML) that involves generating a robust multi-layered structure of nanoparticles, which could remarkably improve vesicle stability that enables release of entrapped drugs in a controllable and sustainable manner in a serum environment. I have demonstrated that this engineered nanoparticle system is capable of co-delivery of multiple hydrophilic/hydrophobic drugs for inducing synergistic antitumor activity, which can be readily adapted as effective treatment options for diseases with unmet medical needs.
As a consequence of their well-defined nanostructure and intrinsic bioactive functionality, virus-based nanoparticles have shown promise for mediating gene delivery. Among various viral nanoparticles, adeno-associated virus (AAV) has been considered as a promising vehicle for human gene therapy based on its ability to infect both dividing and nondividing cells, as well as establish long-term gene expression in vivo without known pathological consequence of infection. Although AAV nanovectors possess a high safety profile and remarkable potential in several disease models, their utilization in many areas of gene therapy is limited by the restricted tissue tropism of AAV. Therefore, retargeting
the viral particle tropism of AAV to desired target cells could not only expand its utility for gene delivery applications, but also mitigate safety issues for use in human gene therapy. In this seminar, the general strategies that I have established for retargeting viral nanoparticles will be discussed in more detail.
In addition, ineffective uptake of drug/gene delivery vectors to target cells in vivo environment always remains obstacles for the clinical translation of the therapeutic vectors. I have developed a general strategy for in vivo modulation of target cells using a biomaterial scaffold by creating optimal in vivo microenvironment where target cells can be recruited and proliferated. This method could remarkably enhance drug/gene delivery efficacy to the target cells in vivo. Many components of the therapeutic strategy proposed in these researches will be presented in the seminar.
Dr. Joo received his Ph.D in chemical engineering emphasized on biological engineering and gene therapy at University of Southern California (USC) in USA and continued the postdoctoral training at USC for nanotechnology and biomaterial design. Dr. Joo has gained extensive experience and knowledge in nanotechnology, drug delivery, gene therapy, biomaterial design, cancer therapy, biological engineering, and molecular biology. His research has been devoted to establish various methodologies for improving drug and gene delivery system by a generic / chemical engineering of nanoparticles and viral vectors, which has been demonstrated in a number of publications and patents, including Nature Biotechnology, ACS Nano, JACS, Small, Biomaterials, Gene Therapy, and so on. Dr. Joo is currently working as a Staff Scientist at a clinical stage gene therapy biotech located in Boston, USA where he has attained a broad experience in clinical trials of gene therapy.