NKG2D-CAR T cells eliminate senescent cells in aged mice and nonhuman primates.
Level 5 - mechanism / opinion, no new human data
Preclinical in vitro and animal model study (mice and nonhuman primates)
PubMed 37585504 · doi:10.1126/scitranslmed.add1951
What was done
NKG2D ligand (NKG2DL) expression was assessed across senescent cells in vitro and in tissues from aged mice and nonhuman primates. Researchers developed chimeric antigen receptor (CAR) T cells targeting NKG2DLs and tested their selectivity against human cells induced into senescence by oncogenic stress, replicative exhaustion, DNA damage, or p16INK4a overexpression. In vivo efficacy and safety were evaluated using mouse NKG2D-CAR T cells in irradiated and naturally aged mice, as well as autologous NKG2D-CAR T cells in aged nonhuman primates.
What was found
NKG2DLs were up-regulated in senescent cells across induction stimuli and in aged animal tissues. Human NKG2D-CAR T cells depleted senescent cells in vitro. In irradiated and aged mice, mouse NKG2D-CAR T cells reduced aging-associated pathologies and improved physical performance. In aged nonhuman primates, autologous NKG2D-CAR T cells deleted naturally occurring senescent cells with no observed adverse effects. The abstract reported no exact numbers, effect sizes, or quantitative measures.
Why it matters
This study demonstrates that NKG2D ligands can serve as targets for senolytic CAR T cells and provides proof-of-concept efficacy and short-term tolerability data in nonhuman primates.
Limits
The study is entirely preclinical with no human clinical data. The abstract reports no quantitative values, sample sizes, or duration of follow-up. Long-term safety and off-target cytotoxicity against healthy tissues expressing basal NKG2D ligands require evaluation in human trials.
Cited by
- supports Senescent cells express ligands on their surface that are recognized by natural killer cells, triggering the innate immune system to clear them.