title: Dual targeting of ErbB2 and MUC1 in breast cancer using chimeric antigen receptors engineered to provide complementary signaling.
abstract: OBJECTIVE
  Chimeric antigen receptor (CAR) engineered T-cells occupy an increasing niche in cancer immunotherapy. In this context, CAR-mediated CD3ζ signaling is sufficient to elicit cytotoxicity and interferon-γ production while the additional provision of CD28-mediated signal 2 promotes T-cell proliferation and interleukin (IL)-2 production. This compartmentalisation of signaling opens the possibility that complementary CARs could be used to focus T-cell activation within the tumor microenvironment.
  
  
  METHODS
  Here, we have tested this principle by co-expressing an ErbB2- and MUC1-specific CAR that signal using CD3ζ and CD28 respectively. Stoichiometric co-expression of transgenes was achieved using the SFG retroviral vector containing an intervening Thosea asigna peptide.
  
  
  RESULTS
  We found that "dual-targeted" T-cells kill ErbB2(+) tumor cells efficiently and proliferate in a manner that requires co-expression of MUC1 and ErbB2 by target cells. Notably, however, IL-2 production was modest when compared to control CAR-engineered T-cells in which signaling is delivered by a fused CD28 + CD3ζ endodomain.
  
  
  CONCLUSIONS
  These findings demonstrate the principle that dual targeting may be achieved using genetically targeted T-cells and pave the way for testing of this strategy in vivo.
authors.affiliation: King's College London, King's Health Partners Integrated Cancer Center, Department of Research Oncology, Guy's Hospital Campus, Great Maze Pond, London, SE1 9RT, UK.
authors.forename: Scott
authors.initials: S
authors.lastname: Wilkie
authors.forename: May C I
authors.initials: MC
authors.lastname: van Schalkwyk
authors.forename: Steve
authors.initials: S
authors.lastname: Hobbs
authors.forename: David M
authors.initials: DM
authors.lastname: Davies
authors.forename: Sjoukje J C
authors.initials: SJ
authors.lastname: van der Stegen
authors.forename: Ana C Parente
authors.initials: AC
authors.lastname: Pereira
authors.forename: Sophie E
authors.initials: SE
authors.lastname: Burbridge
authors.forename: Carol
authors.initials: C
authors.lastname: Box
authors.forename: Suzanne A
authors.initials: SA
authors.lastname: Eccles
authors.forename: John
authors.initials: J
authors.lastname: Maher
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000276:immunology*; D001943:Breast Neoplasms / Q000276:immunology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D016219:Immunotherapy, Adoptive; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D018396:Mucin-1 / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D015398:Signal Transduction / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C413364:ERBIN protein, human; D007376:Interleukin-2; C060192:MUC1 protein, human; D018396:Mucin-1; D011948:Receptors, Antigen, T-Cell; D007371:Interferon-gamma