title: A transgene-encoded cell surface polypeptide for selection, in vivo tracking, and ablation of engineered cells.
abstract: An unmet need in cell engineering is the availability of a single transgene encoded, functionally inert, human polypeptide that can serve multiple purposes, including ex vivo cell selection, in vivo cell tracking, and as a target for in vivo cell ablation. Here we describe a truncated human EGFR polypeptide (huEGFRt) that is devoid of extracellular N-terminal ligand binding domains and intracellular receptor tyrosine kinase activity but retains the native amino acid sequence, type I transmembrane cell surface localization, and a conformationally intact binding epitope for pharmaceutical-grade anti-EGFR monoclonal antibody, cetuximab (Erbitux). After lentiviral transduction of human T cells with vectors that coordinately express tumor-specific chimeric antigen receptors and huEGFRt, we show that huEGFRt serves as a highly efficient selection epitope for chimeric antigen receptor(+) T cells using biotinylated cetuximab in conjunction with current good manufacturing practices (cGMP)-grade anti-biotin immunomagnetic microbeads. Moreover, huEGFRt provides a cell surface marker for in vivo tracking of adoptively transferred T cells using both flow cytometry and immunohistochemistry, and a target for cetuximab-mediated antibody-dependent cellular cytotoxicity and in vivo elimination. The versatility of huEGFRt and the availability of pharmaceutical-grade reagents for its clinical application denote huEGFRt as a significant new tool for cellular engineering.
authors.affiliation: Department of Cancer Immunotherapeutics & Tumor Immunology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA, USA.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Wang
authors.forename: Wen-Chung
authors.initials: WC
authors.lastname: Chang
authors.forename: ChingLam W
authors.initials: CW
authors.lastname: Wong
authors.forename: David
authors.initials: D
authors.lastname: Colcher
authors.forename: Mark
authors.initials: M
authors.lastname: Sherman
authors.forename: Julie R
authors.initials: JR
authors.lastname: Ostberg
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Forman
authors.forename: Stanley R
authors.initials: SR
authors.lastname: Riddell
authors.forename: Michael C
authors.initials: MC
authors.lastname: Jensen
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000235:genetics*; D017209:Apoptosis / Q000235:genetics*; D002469:Cell Separation / Q000379:methods*; D058948:Cell Tracking / Q000379:methods*; D002477:Cells / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D017930:Genes, Reporter; D041722:Genes, Transgenic, Suicide / Q000502:physiology; D018773:Genes, erbB-1; D006801:Humans; D053631:Interleukin Receptor Common gamma Subunit / Q000235:genetics; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D008822:Mice, Transgenic; D010455:Peptides / Q000235:genetics; D023822:Tissue Engineering / Q000379:methods*; D019076:Transgenes / Q000235:genetics*
chemical_list: D000954:Antigens, Surface; C507942:Il2rg protein, mouse; D053631:Interleukin Receptor Common gamma Subunit; D010455:Peptides