CAR-T cells secreting BiTEs circumvent antigen escape without detectable toxicity

Nat Biotechnol. 2019 Sep;37(9):1049-1058. doi: 10.1038/s41587-019-0192-1. Epub 2019 Jul 22.


Chimeric antigen receptor (CAR)-T-cell therapy for solid tumors is limited due to heterogeneous target antigen expression and outgrowth of tumors lacking the antigen targeted by CAR-T cells directed against single antigens. Here, we developed a bicistronic construct to drive expression of a CAR specific for EGFRvIII, a glioblastoma-specific tumor antigen, and a bispecific T-cell engager (BiTE) against EGFR, an antigen frequently overexpressed in glioblastoma but also expressed in normal tissues. CART.BiTE cells secreted EGFR-specific BiTEs that redirect CAR-T cells and recruit untransduced bystander T cells against wild-type EGFR. EGFRvIII-specific CAR-T cells were unable to completely treat tumors with heterogenous EGFRvIII expression, leading to outgrowth of EGFRvIII-negative, EGFR-positive glioblastoma. However, CART.BiTE cells eliminated heterogenous tumors in mouse models of glioblastoma. BiTE-EGFR was locally effective but was not detected systemically after intracranial delivery of CART.BiTE cells. Unlike EGFR-specific CAR-T cells, CART.BiTE cells did not result in toxicity against human skin grafts in vivo.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Bispecific / therapeutic use*
  • Antigens, Neoplasm / immunology*
  • Antigens, Neoplasm / metabolism
  • Cell Differentiation
  • ErbB Receptors
  • Glioblastoma / immunology
  • Glioblastoma / metabolism
  • Glioblastoma / therapy*
  • Humans
  • Mice
  • Neoplasms, Experimental
  • Receptors, Chimeric Antigen*
  • T-Lymphocytes / physiology


  • Antibodies, Bispecific
  • Antigens, Neoplasm
  • Receptors, Chimeric Antigen
  • epidermal growth factor receptor VIII
  • ErbB Receptors