title: A caspase 8-based suicide switch induces apoptosis in nanobody-directed chimeric receptor expressing T cells.
abstract: In accordance with the two-step hypothesis of T cell activation and the observation that stimulation through the T cell receptor (TCR) alone may lead to anergy, we focused on the introduction of co-stimulatory signaling to this type of receptors to achieve optimal activation. Enhanced mRNA and cell surface receptor expression via the co-stimulatory gene fragment (OX40) was confirmed by RT-PCR and flow cytometry. Inclusion of the OX40 co-stimulatory signaling region in series with the TCR led to enhanced antigen-induced IL-2 production after stimulation by MUC1-expressing cancer cell lines as compared to the chimeric receptor without OX40. Moreover, with the aim of maintaining high efficiency, while providing a means of controlling any possible unwanted proliferation in vivo, a regulation system was used. This controls the dimerization of a membrane-bound caspase 8 protein. Toward that goal, pFKC8 and CAR constructs were co-transfected into Jurkat cells, and the level of apoptosis was measured. 24 h after addition of the dimerizer, a 91% decrease in transfected cells was observed.
authors.affiliation: Department of Medical Biotechnology, School of Medical Sciences, Tarbiat Modares University, PO Box: 14115-331 Tehran, Iran.
authors.forename: Sepideh
authors.initials: S
authors.lastname: Khaleghi
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Rahbarizadeh
authors.forename: Davoud
authors.initials: D
authors.lastname: Ahmadvand
authors.forename: Mohammad J
authors.initials: MJ
authors.lastname: Rasaee
authors.forename: Philippe
authors.initials: P
authors.lastname: Pognonec
mesh_terms: D000818:Animals; D017209:Apoptosis; D053181:Caspase 8 / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D018396:Mucin-1 / Q000235:genetics / Q000276:immunology*; D041681:NIH 3T3 Cells; D012333:RNA, Messenger / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D014162:Transfection
chemical_list: D007376:Interleukin-2; C060192:MUC1 protein, human; D018396:Mucin-1; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell; D011993:Recombinant Fusion Proteins; D053181:Caspase 8