Maegan Hoover, MS: No relevant disclosure to display
Introduction/Rationale: Tregs play a key role in establishing and maintaining immune tolerance and homeostasis but despite progress, current Treg therapies face challenges of unstable phenotypes, lack of IL-2 support, and tissue specificity.
Methods: We present a strategy to address these challenges by harnessing a gene editing platform with dual AAV to engineer human regulatory T cells (EngTreg) from bulk CD4+ T cells resulting in the stable expression of FOXP3 and a chemically inducible cytokine signaling complex providing IL-2 signaling support. Additionally, a novel hypoimmune approach improves allogeneic cell persistence by preventing T, B, and NK cell mediated rejection, making possible an off-the-shelf approach. This modular engineering allows for indication specific, interchangeable tissue specific targeting including TCRs, CARs, or inflammation tuned alarmin receptors.
Results: We present transcriptomic and flow cytometry analyses showing EngTregs express higher levels of core Treg and FOXP3 synergy genes, stability markers and tolerogenic proteins compared to cultured Tregs. EngTregs have been tailored for multiple indications: GNTI-122 targets IGRP for T1D, showing strong bystander suppression and disease prevention in mouse models. CAR19 EngTregs target B-cell driven autoimmune diseases with better safety compared to CAR-T cells. Gut epithelium targeting EngTregs ameliorate disease in murine IBD models. Tissue EngTregs target alarmin mediated inflammation and show efficacy in models of lung injury, AKI, and stroke.
Conclusion: Together, these data support EngTregs as a potent, stable, and versatile cell therapy platform for autoimmune, inflammatory, and ischemic diseases.