GNTI-823: Engineered Allogeneic Tissue Regulatory T Cells Ameliorate AKI via Immune Modulation and Tissue Repair

Background: Regulatory T cells (Tregs) are essential for immune tolerance and tissue homeostasis. A specialized subset of thse cells, dubbed Tissue Tregs, reside in non-lymphoid organs where they regulate immune homeostasis and support repair through direct (e.g. expression of repair cytokines) and indirect (e.g. modulating macrophage subsets) in response to the inflammatory microenvironemnt. Acute kidney injury (AKI) and chronic kidney disease (CKD), marked by uncontrolled inflammation and faulty repair processes, remains a significant clinical challenge with limited treatment options. Methods: We engineered GNTI-823, an allogeneic Tissue EngTreg, from peripheral blood CD4 T cells using CRISPR-based editing to induce stable FOXP3 expression, a rapamycin-inducible IL-2 signaling complex, and an alarmin-responsive transgene. An allogeneic murine surrogate (mEngTreg) was created from CB6F1 derived CD4 T cells. In vivo efficacy was assessed in the unilateral ischemia-reperfusion injury with D7 contralateral nephrectomy (uNxIR) and cisplatin-induced AKI models in C57BL/6 mice. Results: GNTI-823 expressed canonical Treg markers (e.g. FOXP3, CD25, CTLA4) and following IL-33 co-culture, upregulated expression of key homing receptors (e.g. CCR4, CCR8) and tolerogenic mediators (CD39, TIGIT). GNTI-823 sequestered pro-inflammatory cytokines in vitro (e.g. TNF, IL-2), and upregulated repair cytokines (e.g. IL-13). In a D7 uNxIR model, mEngTreg treated mice exhibited significantly reduced serum Kim-1 levels, and normalization of the renal macrophage subsets by F4/80 (IHC) and CD64, MHCII (flow cytometry). Histopathology analysis revealed improvements in clinically relevant readouts including, tubular degeneration, cast formation, tubular dilation, and fibrosis. In the cisplatin model, mEngTreg treated animals showed improvement in BUN, NGAL, Kim-1, and albumin levels. Finally, metanalysis of kidney injury models with mEngTregs revealed an improvement in survival compared to disease control groups. Conclusion: Engineered allogeneic Tissue EngTregs (GNTI-823) effectively modulate inflammation and promote renal repair in preclinical AKI models. These findings support the development of an off-the-shelf cell therapy for acute inflammatory diseases, including acute ischemic and immune-mediated kidney diseases. Funding: Commercial Support - T1D Fund, Breakthrough T1D, RA Capital, Orbimed, Novartis Venture Fund, Private Foundation Support