Unlike small molecules, large molecules including proteins and nucleic acids are unable to penetrate the cellular membrane. However, effectively delivering proteins and nucleic acids into cells could enable the treatment of a number of previously incurable diseases. Here, the PI proposes to create natural small lipid vesicles that contain pores. These will allow large molecules to be transported directly into cells. To load these small lipid vesicles with therapeutic molecules, biomaterials composed of nucleic acids will be engineered. To ensure that the lipid vesicles will only target specific cells, the vesicles will be decorated with molecules that can detect diseased cells. This research is expected to have broad impact across several scientific disciplines including biomaterials, nucleic acid and drug delivery, nanotechnology, and cell-mimicking materials. The fundamental knowledge gained from the proposal will significantly change the way that membrane-impermeable compounds are delivered to cells, especially for large molecules. This has important implications for human health because these carriers should allow diseases that are currently undruggable to be treated more safely and efficiently. The project will also enhance the nation's education infrastructure by developing a new biomaterials curriculum for graduate students and by delivering interactive teaching modules to high schools. Further, this project seeks to establish a mentoring-intensive program that will foster biomaterials research for minority and female undergraduate students. It will also establish a network of support for biomaterials graduate, undergraduate, and high school students.
TECHNICAL In this CAREER proposal, the PI plans to develop a novel class of cell-mimicking carriers, termed poresomes. These poresomes will be used to deliver macromolecules to the cytoplasm while bypassing endosomes. Despite tremendous progress in nanoscience, the cytoplasmic delivery of membrane-impermeable compounds such as negatively charged RNA remains challenging. This is because a significant fraction of the RNA that is delivered remains trapped in the endosomes, where it ultimately degrades. The objective of this CAREER proposal is to overcome these challenges by engineering cell-mimicking RNA-loaded lipid vesicles that are equipped with pores composed of connexin membrane channels. It is hypothesized that microRNA(miRNA)-loaded poresomes will connect to the connexin membrane channels of recipient cells to form gap junctions. In this way, miRNAs will be directly delivered into the cytoplasm whilst bypassing the degradative endosomal and lysosomal environments (Objective 1). Further, to effectively load poresomes with therapeutic cargo, the PI proposes to synthesize EXOmers, RNA-based sequences that are capable of exploiting the cellular trafficking machinery used to actively sort macromolecules into poresomes. Structure activity analyses will be performed to develop highly efficient sequences (Objective 2). Third, multifunctional poresomes that target non-internalizing receptors will be engineered to mediate cellular anchoring and facilitate miRNA transport through gap junctions (Objective 3). The educational goals are to (i) increase participation of underrepresented students through more understandable, relatable, and accessible science and (ii) improve biomaterials and nanoscience education for graduate, undergraduate, and high school students. We will harness the learning advantages provided by visualization and animation to teach complex scientific subject matter. The integrative nature of our education outreach program should improve the communication skills of both graduate and undergraduate students.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
