IF a uPAR-specific chimeric antigen receptor is stably transduced into allogeneic human Vγ9Vδ2 γδ T cells (anti-uPAR CAR-γδ T cells), generating an inherently dual-sensing "AND-gate" senolytic living drug, and this product is administered as a single intravenous infusion (~5×10⁶ cells per mouse) to naturally aged (24-month-old) male and female C57BL/6 mice,

THEN durable multi-tissue clearance of uPAR⁺ senescent cells (≥60% reduction in p21⁺/p16⁺ co-positive cells by IHC at 6 months post-infusion) will be observed across the liver, visceral adipose tissue, lung, kidney, and hippocampal subgranular zone, accompanied by: restoration of hippocampal neurogenesis (≥40% increase in BrdU⁺/DCX⁺ cells in the SGZ); improved systemic metabolic function (reduced glucose tolerance AUC vs. aged controls); and a markedly safer cytokine release profile compared to conventional anti-uPAR αβ CAR-T cells — with no detectable graft-versus-host disease (GvHD), no grade ≥2 cytokine release syndrome, and no on-target off-tumor toxicity in uPAR-low healthy tissues —

BECAUSE the following causal chain is supported by cross-paper synthesis:

1. uPAR (PLAUR) is broadly and robustly upregulated on the surface of senescent cells across liver, lung, adipose, kidney, heart, and brain in aged mice, confirmed across three independent senescence models by comparative RNA-seq and protein profiling, providing a pan-tissue surface target for engineered cytolytic cells (uPAR broadly induced on senescent cells across tissues)[https://doi.org/10.1038/s41586-020-2403-9].

2. Conventional αβ CAR-T cells targeting uPAR achieve durable clearance of senescent cells, form long-lived memory populations after a single infusion, and prevent age-related metabolic dysfunction in aged and prophylactically treated mice — establishing the proof-of-principle for a one-time "living senolytic" approach (uPAR CAR-T cells establish persistent memory and long-lasting efficacy)[https://doi.org/10.1038/s41586-020-2403-9].

3. However, uPAR is expressed at low baseline levels on activated macrophages, endothelial cells, and other non-senescent populations, creating a residual on-target off-tumor risk with conventional single-antigen CAR-T cells that relies on antigen-density thresholding alone [SPECULATIVE risk, acknowledged in Amor et al. 2020]; engineering a dual-recognition requirement substantially reduces this risk without requiring complex synthetic logic-gate circuits.

4. Vγ9Vδ2 γδ T cells natively and independently recognize NKG2D ligands (MICA, MICB, ULBP1-3) and phosphoantigens via their γδ TCR — ligands that are co-upregulated on senescent cells as part of the SASP-associated stress response — creating an inherent biological AND-gate: a CAR-γδ T cell is fully activated only when a target cell co-presents high-density uPAR (CAR signal) AND NKG2D ligands/phosphoantigens (native γδ TCR signal), a combinatorial requirement that healthy uPAR-low cells cannot satisfy (γδ T cells selectively kill s...

SENS category: GlycoSENS

Key references: • doi.org/10.1038/s41586-020-2403-9]. • doi.org/10.1101/2025.05.05.652251]. • doi.org/10.1016/j.stemcr.2021.12.010]. • doi.org/10.1038/s41467-020-18039-x]. • doi.org/10.1038/s41598-021-99852-2].