Date of Award
5-14-2024
Degree Name
Doctor of Philosophy (PhD)
Degree Type
Dissertation
Abstract
Immunoengineering continues to revolutionize healthcare, generating new approaches for treating previously intractable diseases. In chronic inflammatory diseases such as rheumatoid arthritis (RA), a chronic autoimmune disease characterized by joint inflammation and destruction, anti-cytokine treatments have previously been at that forefront of therapeutic innovation. However, while many of the existing anti-cytokine treatments are successful for a subset of patients, these treatments can also pose severe adverse events and off-target effects from systemic administration of anti-inflammatory drugs at constant high dosages or a lack of disease-specific targets. These limitations have motivated the development of new treatment strategies that are well-controlled, precise, safe, and efficacious. To address these challenges, cell therapies have emerged as a promising approach for targeted drug delivery systems as recent advances in the field of synthetic biology and genome editing have enabled rapid and precise engineering of the cellular genome. As macrophages are one of the key denominators of both the initiation and progression of chronic inflammation in RA, this thesis explores their potential as a cell therapy for RA. The first aim of this thesis focused on the development and characterization of engineered macrophages for targeted anti-inflammatory drug delivery. We explored the use of two clinically used biologics, soluble tumor necrosis factor (TNF) receptor 1 and interleukin-1 (IL-1) receptor antagonist. Two unique approaches, CRISPR-Cas9 and lentiviral gene therapy, were utilized to create engineered macrophages that sense and respond to their biochemical environment in a pre-programmed manner. Both murine induced pluripotent derived macrophages and bone marrow derived macrophages (BMDMs) were engineered to examine the effect of origin on the potential for macrophage cell therapy. Macrophages genetically engineered with the CRISPR or lentiviral systems could detect dynamic cues from the environment and used a negative feedback loop to produce their prescribed biologic therapy in a transient and autoregulated manner to mediate their own inflammatory activation. In the second aim, as the lentiviral BMDM system possessed a larger therapeutic effect, this system was further examined for therapeutic potential in co-culture with key inflammatory responsive cells in an RA joint. Engineered BMDMs, through robust production of therapeutic IL-1Ra, were able to protect synovial fibroblasts and tissue engineered cartilage from inflammatory dysregulation as well as cytokine-induced degradation in both direct and transwell co-culture. Finally, in the last aim we used both an acute joint injury model as well as the well-established K/BxN serum transfer arthritis mouse model to confirm the presence and homing capacity of engineered macrophages upon delivery. In the K/BxN model of RA, mice treated with therapeutic macrophages demonstrated moderate disease mitigation as well as decreased pain and inflammation. This work will provide novel insights into the therapeutic potential of macrophage-based drug delivery strategies and emphasize the strength of macrophages as therapeutic systems in controlling chronic inflammation.
Language
English (en)
Chair
Farshid Guilak