Tailored designs and applications of soft nanomaterials for advancing chimeric antigen receptor macrophage engineering
Creators: name: Chuang, Skylar T.
Publisher: name: No Publisher Supplied
Year: 2024

description: Cellular immunotherapy, a revolutionary approach in the field of cancer treatment, has garnered significant attention in recent years. This innovative strategy involves utilizing the patient's own immune system or genetically modified immune cells to identify and eliminate malignant cells, offering a promising alternative to conventional therapies. In particular, chimeric antigen receptor (CAR) T-cell therapy and adoptive transfer of stem cells have emerged as two prominent therapies, demonstrating remarkable success in the treatment of hematological malignancies and solid tumors. Despite the unparalleled potential, challenges persist, including managing adverse immune reactions and optimizing the efficacy and durability of the immune response. This dissertation details research efforts in engineering approaches for cellular immunotherapy in combination with nanotechnology. In the first chapter, we highlighted the recent breakthroughs in cellular immunotherapy, addressed the underlying mechanisms and clinical applications, and discussed ongoing research efforts aimed at expanding its scope and enhancing its safety and efficacy profile. Understanding the intricacies of cellular immunotherapy is imperative for advancing personalized medicine and paving the way for a transformative paradigm in cancer treatment. In the second and third chapters, we discussed the combinatorial approach of synthetic nanomaterials with non-viral genetic engineering to stimulate and generate CAR macrophages (CAR-Ms). The immunosuppressive tumor microenvironment (TME) represents a major hurdle to successful chimeric antigen receptor (CAR) T-cell immunotherapy for solid tumors. As a potential strategy to mitigate the TME, we engineered macrophages with CAR-Ms using poly beta amino ester nanoparticles (PBAE NPs). PBAE NPs enabled the co-delivery of the CAR transposon and transposase for sustained expression, as well as priming of the transfected macrophages. PBAE NPs elicited a pro-inflammatory phenotype in the macrophages upon transfection, supported by the upregulated expression of pro-inflammatory cytokines and unconventional integrin receptors CD11a and CD11c. In addition, metabolic profiling showed a reprogramming of these macrophages with metabolites characteristic of pro-inflammatory macrophages. Further, we developed a nonviral approach for optimizing the co-transfection of CAR using PBAE NPs in macrophages, utilizing the combined adjuvant effect of PBAE and target specificity of CAR for enhanced phagocytosis in a pancreatic cancer model. Our results enable a better design of synthetic nanocarriers for in vivo CAR-M immunotherapy.In the latter chapters, we explored the potential of CAR-Ms for chronic inflammatory disease application, using atherosclerosis as a proof-of-concept demonstration. Atherosclerosis is a chronic inflammatory disease defined by the continual infiltration of plasma monocytes, the release of pro-inflammatory cytokines and reactive oxygen species (ROS), and the accumulation of apoptotic cells. The removal of dying cells, which is known as efferocytosis, is an indispensable part of ending inflammation and is a crucial step in the apoptotic process. On the other hand, the inflammatory microenvironment of the atherosclerotic plaque frequently affects the biology of both apoptotic cells and resident phagocytes, rendering efferocytosis dysfunctional. To overcome this problem, we developed an immune-engineered scavenger platform that combines a nano-drug delivery system (NDDS) with cell therapy to improve efferocytosis. More specifically, macrophages modified with chimeric antigen receptors (CAR) could specifically target and engulf phagocytosis-resistant apoptotic cells. In both normal and inflammatory circumstances, CAR macrophages (CAR-Ms) exhibit activity equivalent to antibody blockage. The surface of CAR macrophages was modified with ROS-responsive therapeutic nanoparticles to improve their cell effector activities. Nanoparticles synthesized by nanoprecipitation can slowly disintegrate in the presence of ROS, allowing extended drug release and activation of the liver X receptor (LXR) pathway. The combination of immunoengineering and nano-drug delivery systems (NDDSs) activates lipid efflux pumps, which clear cell debris and reduce inflammation. We further demonstrated that undifferentiated CAR macrophages could travel through a micro-fabricated vessel system, suggesting the potential therapeutic utility of our platform. We believe that this cell therapy platform, combined with NDDSs, could lead to the development of next-generation cardiovascular disease therapeutics. Specifically, this innovative platform can potentially address the unmet need for more targeted and effective treatment options for patients with cardiovascular disease. In addition, by leveraging the unique properties of NDDSs, we can enhance the therapeutic potential of this cell therapy platform and improve patient outcomes. With further research and development, we are optimistic about the potential of this approach to revolutionize the treatment of cardiovascular disease and improve the lives of millions of patients worldwide.