This collaborative research award by the Biomaterials program in the Division of Materials Research, made to the University of Massachusetts and University of Colorado, is to carry out experiments and simulations to understand polycation-DNA complexation towards improved non-viral gene therapy using synthetic polymers. This award cofounded by the Polymer program in the Division of Materials Research seeks to understand DNA complexation with tailored macromolecular cationic architectures, and the impact of different modes of complexation on DNA delivery. The proposed experiments focus on synthetic polycations, in which cationic oligomers are grafted pendent to a polymer backbone at precise inter-graft spacing. This architecture platform will be augmented by insertion of nuclear localization sequences into the backbone in preferred orientations. Polyplex stability and DNA delivery efficiency will be determined in cell culture under a variety of conditions, aiming to combine high cell viability with excellent transfection efficiency. The computational approach, carried out in conjunction with experiments, will involve: 1) atomistic simulations to explain the effects of systematically varying architectural and chemical features of the polycation on free energy of DNA-polycation binding, and in turn connect to experimental trends in polyplex stability; and 2) coarse-grained simulations that focus on polyplex structure (relative size, shape and charge) as a function of polycation architecture and composition, which directly relate to experiments on polyplex structure, and carries key implications for serum stability and transfection efficiency. In addition to transforming the understanding and practice of polymer-based gene therapy, the project will open a unique opportunity to train graduate students in an integrated multidisciplinary experimental/theoretical project through regular inter-group interactions via SkypeTM sessions, and by devoting time and resources for the researchers to visit their collaborator's institution. The PIs will maintain a commitment to participation of undergraduates in this research project, utilizing the Undergraduate Research Opportunity and Research Experience for Undergraduates programs at University of Colorado and University of Massachusetts. Planned workshop activities would connect U.S. and worldwide leaders in both experiment and computation of polyelectrolytes and complexation, and would involve young scientists at the outset of their careers, through the organization of meetings at the Telluride Science Research Conference, a highly interactive setting for research presentations and discussions.
The design and implementation of effective polymer based gene delivery will advance genomic research and open new avenues to deliver DNA for treating many diseases, such as muscular dystrophy. There is a pressing need for improved DNA delivery, since currently used delivery methods, based on viruses, have their own health and safety risks. In this collaborative project, computer simulations will help experimentalists decide which polymers to prepare for complexing DNA, and how to modify those polymers for most effective therapeutic action. Outcomes of this project include both the development of novel and more efficient DNA delivery agents, and a more thorough fundamental understanding of charged polymers and their interactions with key therapeutic biomolecules such as DNA and RNA. The multidisciplinary nature of this experimental/theoretical project will allow for a well-rounded training of students in Massachusetts and Colorado, at the high school, undergraduate, and graduate levels, in areas of molecular simulation, polymer synthesis, and gene delivery.
