CTLA-4 tail fusion enhances CAR-T antitumor immunity

Nat Immunol. 2023 Sep;24(9):1499-1510. doi: 10.1038/s41590-023-01571-5. Epub 2023 Jul 27.


Chimeric antigen receptor (CAR)-T cells are powerful therapeutics; however, their efficacy is often hindered by critical hurdles. Here utilizing the endocytic feature of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) cytoplasmic tail, we reprogram CAR function and substantially enhance CAR-T efficacy in vivo. CAR-T cells with monomeric, duplex or triplex CTLA-4 cytoplasmic tails (CCTs) fused to the C terminus of CAR exhibit a progressive increase in cytotoxicity under repeated stimulation, accompanied by reduced activation and production of proinflammatory cytokines. Further characterization reveals that CARs with increasing CCT fusion show a progressively lower surface expression, regulated by their constant endocytosis, recycling and degradation under steady state. The molecular dynamics of reengineered CAR with CCT fusion results in reduced CAR-mediated trogocytosis, loss of tumor antigen and improved CAR-T survival. CARs with either monomeric (CAR-1CCT) or duplex CCTs (CAR-2CCT) have superior antitumor efficacy in a relapsed leukemia model. Single-cell RNA sequencing and flow cytometry analysis reveal that CAR-2CCT cells retain a stronger central memory phenotype and exhibit increased persistence. These findings illuminate a unique strategy for engineering therapeutic T cells and improving CAR-T function through synthetic CCT fusion, which is orthogonal to other cell engineering techniques.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abatacept
  • CTLA-4 Antigen / genetics
  • Cell Line, Tumor
  • Cytokines / metabolism
  • Immunotherapy, Adoptive / methods
  • Receptors, Antigen, T-Cell / genetics
  • Receptors, Chimeric Antigen* / genetics
  • Receptors, Chimeric Antigen* / metabolism
  • T-Lymphocytes


  • Receptors, Chimeric Antigen
  • CTLA-4 Antigen
  • Cytokines
  • Abatacept
  • Receptors, Antigen, T-Cell