Work

203 Dual targeting of uPAR and MICA/B with multiplexed-engineered CAR T cells offers a unique therapeutic strategy in fibrotic disease

Year: 2026

Type: conference-abstract

Abstract: Background Urokinase plasminogen activator receptor (uPAR) is a key contributor of pathological tissue remodeling and cancer metastasis. MHC class I polypeptide-related sequence A/B (MICA/B) are stress ligands expressed in fibrotic, senescent and tumor cells. A dual uPAR and MICA/B-targeting approach was explored using chimeric antigen receptor (CAR) T-cell technology, and the level of molecular precision in targeting such complex pathologies was evaluated. Employing an in vivo model of radiation induced pulmonary fibrosis (RIPF) and preclinical assays related to the genesis of the fibrotic tumor microenvironment (TME), we assessed the mitigation and reversion of fibrosis and elimination of cancer with a novel dual-antigen targeting strategy combing anti-uPAR and anti-MICA/B CAR (α-umCAR) T cells.Methods Focal radiation was delivered to the left lung of C57BL/6 mice to induce fibrosis. Following treatment with murine uPAR-targeted CAR T cells, lung tissue was evaluated for collagen deposition and expression of uPAR, MULT1, and F4/80. To evaluate dual uPAR and MICA/B targeting, α-umCAR T cells were generated through multiplexed-engineering of induced pluripotent stem cells (iPSCs) with CAR and hnCD16 to enable antibody-dependent cellular cytotoxicity. Engineered iPSC lines were then differentiated into T cells.Results In a murine model of RIPF, uPAR-targeted CAR T cells administered six days post-irradiation reduced fibrotic burden and decreased the frequency of uPAR +, MULT1+, and F4/80+ cells within the irradiated region (figure 1A). Irradiation co-upregulated uPAR and the MICA/B functional analogue MULT1. Importantly, this pattern was conserved in human disease, where IHC staining revealed uPAR and MICA/B were similarly co-upregulated in malignant cells and fibrotic TME (figure 1B), with radiation exposure of fibroblast (figure 1C), and cancer cell lines (figure 1D) in vitro. In a 3D-spheroid killing assay recapitulating the structural heterogeneity of solid tumors, both fibroblast and cancer cell populations were effectively targeted in a CAR- or hnCD16-dependent manner (figure 1E). Finally, dual- targeting by α-umCAR T cells conferred more potent and durable target clearance relative to single-CAR controls, underscoring the therapeutic advantage of this combinatorial strategy for eliminating complex fibrotic disease (figure 1F).Conclusions This work demonstrates the therapeutic potential of targeting uPAR and MICA/B – antigens that are co-upregulated in both cancer and fibrotic disease. Targeting uPAR ameliorates fibrosis and a combination strategy with MICA/B targeting significantly broadens CAR T-cell potency and disease recognition. We are currently investigating the potential of this dual targeting approach with the development of α-umCAR T cells that incorporate additional genetic edits for improved performance in fibrotic settings.Ethics Approval The animal studies within were reviewed and approved by the Institutional Animal Care and Use Committee (IACUC).Abstract 203 Figure 1Dual targeting of uPAR and MICA/B with multiplexed-engineered CAR T cells offers a unique therapeutic strategy in fibrotic disease. (A) Trichrome, uPAR, MULT1, and macrophage (F4/80) staining of murine lungs. Human uPAR or MICA/B expression in (B) tumor tissue or (C-D) cell lines. Dual targeting in (E) 3D fibroblast/tumor spheroid or (F) ovarian targets

Source: Journal for ImmunoTherapy of Cancer

DOI: 10.1136/jitc-2026-sitc2026.0203