Project Summary: The general scientific community already separates different layers or subcellular fractions (i.e., membrane vs. cytoplasm vs. nucleus) as well as subcomponent organelles/machinery (such as mitochondria, lysosomes, etc.) in order to study and better understand cell function. This Trailblazer research proposal seeks to discover how we might repurpose such components, with major emphasis presently on nuclear transfer or exchange as part of a new synthetic biology approach in creating cell-based therapies. Such efforts will lead to the development of a massively expanded toolbox of interventional therapies with a wide array of potential downstream applications in biomedicine (i.e., treatments for cancer, genetic and infectious disease, autoimmunity, and tissue injury and repair). This will be achieved through the following: 1) Generate methods to efficiently isolate nuclei from macrophage and T cells for fusion into enucleated red blood cells and platelets. Methods for nuclear isolation will first be optimized using drug and density centrifugation-induced cellular blebbing and fractionation to isolate nuclei- vs. cytoplasmic component- containing vesicles, called karyoplasts and cytoplasts, respectfully. Karyoplasts will be derived from innate immune macrophage and adaptive immune T cells, and then fused (with PEG) into naturally enucleated RBCs and platelets, and derived cell constructs will be monitored for viability and function over time. 2) Develop storage, freezing, and thawing requirements to maintain viability of cell-derived cytoplasts and karyoplasts, and fusion constructs. This will be done by exploring different freezing media types, constituent chemical concentrations, or altered protocol temperature kinetics to both store (short vs. long- term) as well as thaw cells or their components with preserved structure and function (Figure 1, middle). 3) Characterize macrophage- & T cell-derived cytoplasts, as well as new variant cells following nuclear exchange between enucleated macrophage and T cell bodies. Prior enucleation studies show modified cell behavior, therefore it is not only of interest to investigate nuclear exchange but also what happens to enucleated cells. In addition, nuclear exchange will be attempted with both fresh as well as frozen karyoplast and cytoplast components, with all fusion constructs tested for morphology/viability, proliferation, cytokine expression, and behaviors either derived or distinct from donor cells. This approach will also allow us to determine how constructs may be tunable as part of a larger plug and play system. 4) Test new constructs in functional assays in vitro and in a therapeutic cancer model in vivo. This strategy will provide a platform to create new cell behaviors related to functional activities like macrophage- related adherence and phagocytosis, as well as T cell-mediated perforin/granzyme cytolysis. Therefore, constructs will be tested in vitro in adhesion, migration, and co-culture (cytolysis) assays as well as for anti-tumor activity in vivo in mice.

Project Narrative: This innovational Trailblazer research project seeks to discover how we might re-purpose cellular subcomponents such as the nucleus in a way that makes them readily available in lipid bilayer vesicles for immediate recombination efforts into different cell types. This work also involves efforts to store and subsequently reconstitute these individual components to keep them alive and viable, to be mixed and matched as part of a new synthetic biology approach in creating new cell-like therapeutic platforms. In so doing, we can vary the donor and recipient cells (i.e., mouse or human macrophage and T cell lines) of these components to not only understand how basic behaviors of a cell are affected by organelle contribution and alteration at a much higher level than is presently available but to also create new cell entities with either hybrid functions (i.e., from two different donor cells) or perhaps with improved functionality (behavior and/or magnitude) over that which already exists in nature as a result of mechanisms of selection that have occurred throughout evolution. This will lead to the development of a massively expanded toolbox of interventional therapies with a wide array of potential downstream applications in biomedicine (i.e., treatments for cancer, genetic and infectious disease, autoimmunity, and tissue injury and repair).