title: Preclinical Assessment of CD171-Directed CAR T-cell Adoptive Therapy for Childhood Neuroblastoma: CE7 Epitope Target Safety and Product Manufacturing Feasibility.
abstract: OBJECTIVE
  The identification and vetting of cell surface tumor-restricted epitopes for chimeric antigen receptor (CAR)-redirected T-cell immunotherapy is the subject of intensive investigation. We have focused on CD171 (L1-CAM), an abundant cell surface molecule on neuroblastomas and, specifically, on the glycosylation-dependent tumor-specific epitope recognized by the CE7 monoclonal antibody.
  
  
  METHODS
  CD171 expression was assessed by IHC using CE7 mAb in tumor microarrays of primary, metastatic, and recurrent neuroblastoma, as well as human and rhesus macaque tissue arrays. The safety of targeting the CE7 epitope of CD171 with CE7-CAR T cells was evaluated in a preclinical rhesus macaque trial on the basis of CD171 homology and CE7 cross reactivity. The feasibility of generating bioactive CAR T cells from heavily pretreated pediatric patients with recurrent/refractory disease was assessed.
  
  
  RESULTS
  CD171 is uniformly and abundantly expressed by neuroblastoma tumor specimens obtained at diagnoses and relapse independent of patient clinical risk group. CD171 expression in normal tissues is similar in humans and rhesus macaques. Infusion of up to 1 × 108/kg CE7-CAR+CTLs in rhesus macaques revealed no signs of specific on-target off-tumor toxicity. Manufacturing of lentivirally transduced CD4+and CD8+CE7-CAR T-cell products under GMP was successful in 4 out of 5 consecutively enrolled neuroblastoma patients in a phase I study. All four CE7-CAR T-cell products demonstrated in vitro and in vivo antitumor activity.
  
  
  CONCLUSIONS
  Our preclinical assessment of the CE7 epitope on CD171 supports its utility and safety as a CAR T-cell target for neuroblastoma immunotherapy. Clin Cancer Res; 23(2); 466-77. ©2016 AACR.
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Annette
authors.initials: A
authors.lastname: Künkele
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.|Fred Hutchinson Cancer Research Center, Seattle, Washington.|Seattle Children's Hospital, Department of Pediatrics, University of Washington, Seattle, Washington.
authors.forename: Agne
authors.initials: A
authors.lastname: Taraseviciute
authors.affiliation: Seattle Children's Hospital, Department of Pathology, University of Washington, Seattle, Washington.
authors.forename: Laura S
authors.initials: LS
authors.lastname: Finn
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Johnson
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, Washington.|Department of Medicine, University of Washington, Seattle, Washington.
authors.forename: Carolina
authors.initials: C
authors.lastname: Berger
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Olivia
authors.initials: O
authors.lastname: Finney
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Cindy A
authors.initials: CA
authors.lastname: Chang
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Lisa S
authors.initials: LS
authors.lastname: Rolczynski
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Christopher
authors.initials: C
authors.lastname: Brown
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Mgebroff
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, Washington.
authors.forename: Michael
authors.initials: M
authors.lastname: Berger
authors.affiliation: Seattle Children's Hospital, Department of Pediatrics, University of Washington, Seattle, Washington.
authors.forename: Julie R
authors.initials: JR
authors.lastname: Park
authors.affiliation: Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington. michael.jensen@seattlechildrens.org.|Seattle Children's Hospital, Department of Pediatrics, University of Washington, Seattle, Washington.|University of Washington, Department of Bioengineering, Seattle, Washington.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Jensen
mesh_terms: D000818:Animals; D000074322:Antineoplastic Agents, Immunological / Q000008:administration & dosage / Q000276:immunology; D045744:Cell Line, Tumor; D000939:Epitopes / Q000276:immunology; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D016219:Immunotherapy, Adoptive; D016086:Lentivirus / Q000235:genetics; D008253:Macaca mulatta; D009364:Neoplasm Recurrence, Local / Q000276:immunology / Q000473:pathology / Q000628:therapy; D039842:Neural Cell Adhesion Molecule L1 / Q000235:genetics / Q000276:immunology*; D009447:Neuroblastoma / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000074322:Antineoplastic Agents, Immunological; D000939:Epitopes; D039842:Neural Cell Adhesion Molecule L1; D011948:Receptors, Antigen, T-Cell