Ex vivo activation of the GCN2 pathway metabolically reprograms T cells, leading to enhanced adoptive cell therapy

Cell Rep Med. 2024 Mar 19;5(3):101465. doi: 10.1016/j.xcrm.2024.101465. Epub 2024 Mar 8.


The manipulation of T cell metabolism to enhance anti-tumor activity is an area of active investigation. Here, we report that activating the amino acid starvation response in effector CD8+ T cells ex vivo using the general control non-depressible 2 (GCN2) agonist halofuginone (halo) enhances oxidative metabolism and effector function. Mechanistically, we identified autophagy coupled with the CD98-mTOR axis as key downstream mediators of the phenotype induced by halo treatment. The adoptive transfer of halo-treated CD8+ T cells into tumor-bearing mice led to robust tumor control and curative responses. Halo-treated T cells synergized in vivo with a 4-1BB agonistic antibody to control tumor growth in a mouse model resistant to immunotherapy. Importantly, treatment of human CD8+ T cells with halo resulted in similar metabolic and functional reprogramming. These findings demonstrate that activating the amino acid starvation response with the GCN2 agonist halo can enhance T cell metabolism and anti-tumor activity.

Keywords: 4-1BB; CD8(+) T cell; GCN2; Halofuginone; adoptive Cell therapy; autophagy; immunometabolism; immunotherapy.

MeSH terms

  • Amino Acids
  • Animals
  • CD8-Positive T-Lymphocytes*
  • Humans
  • Immunotherapy
  • Immunotherapy, Adoptive / methods
  • Mice
  • Neoplasms* / pathology


  • Amino Acids