Mechanistic and pharmacodynamic studies of DuoBody-CD3x5T4 in preclinical tumor models

Life Sci Alliance. 2022 Sep 8;5(11):e202201481. doi: 10.26508/lsa.202201481. Print 2022 Nov.


CD3 bispecific antibodies (bsAbs) show great promise as anticancer therapeutics. Here, we show in-depth mechanistic studies of a CD3 bsAb in solid cancer, using DuoBody-CD3x5T4. Cross-linking T cells with tumor cells expressing the oncofetal antigen 5T4 was required to induce cytotoxicity. Naive and memory CD4+ and CD8+ T cells were equally effective at mediating cytotoxicity, and DuoBody-CD3x5T4 induced partial differentiation of naive T-cell subsets into memory-like cells. Tumor cell kill was associated with T-cell activation, proliferation, and production of cytokines, granzyme B, and perforin. Genetic knockout of FAS or IFNGR1 in 5T4+ tumor cells abrogated tumor cell kill. In the presence of 5T4+ tumor cells, bystander kill of 5T4- but not of 5T4-IFNGR1- tumor cells was observed. In humanized xenograft models, DuoBody-CD3x5T4 antitumor activity was associated with intratumoral and peripheral blood T-cell activation. Lastly, in dissociated patient-derived tumor samples, DuoBody-CD3x5T4 activated tumor-infiltrating lymphocytes and induced tumor-cell cytotoxicity, even when most tumor-infiltrating lymphocytes expressed PD-1. These data provide an in-depth view on the mechanism of action of a CD3 bsAb in preclinical models of solid cancer.

MeSH terms

  • Antibodies, Bispecific* / pharmacology
  • CD3 Complex / pharmacology
  • CD8-Positive T-Lymphocytes
  • Cytokines
  • Cytotoxicity, Immunologic
  • Granzymes / pharmacology
  • Humans
  • Neoplasms* / drug therapy
  • Perforin / pharmacology
  • Programmed Cell Death 1 Receptor


  • Antibodies, Bispecific
  • Granzymes
  • CD3 Complex
  • Perforin
  • Programmed Cell Death 1 Receptor
  • Cytokines