title: Donor lymphocytes expressing the herpes simplex virus thymidine kinase suicide gene: detailed immunological function following add-back after haplo-identical transplantation.
abstract: OBJECTIVE
  Haplo-identical hematopoietic stem cell transplantation (HSCT) with add-back of donor lymphocytes expressing the herpes simplex virus thymidine kinase suicide gene (TK cells) is one of the most widely applied promising new gene therapy approaches. However, the immunological status of added-back TK cells after HSCT has yet to be well characterized.
  
  
  METHODS
  We investigated TK cells through the use of flow cytometry, T-cell receptor (TCR) Vβ repertoire spectratyping and linear amplification-mediated polymerase chain reaction followed by insertion site analysis in a patient enrolled in our clinical trial.
  
  
  RESULTS
  A comparison of onset with remission of acute graft-versus-host disease confirmed that TK cells were predominantly eliminated and that proliferative CD8(+) non-TK cells were also depleted in response to ganciclovir administration. The TCR Vβ-chain repertoire of both TK cells and non-TK cells markedly changed after administration of ganciclovir, and, whereas the TCR repertoire of non-TK cells returned to a normal spectratype long after transplantation, that of TK cells remained skewed. With the long-term prophylactic administration of acyclovir, TK cells oligoclonally expanded and the frequency of spliced variants of TK cells increased. Known cancer-associated genes were not evident near the oligoclonally expanded herpes simplex virus (HSV)-TK insertion sites.
  
  
  CONCLUSIONS
  We demonstrate obvious differences in immunological status between TK cells and non-TK cells. In addition, we speculate that long-term prophylactic administration of acyclovir increases the risk of oligoclonal expansion of spliced forms of TK cells.
authors.affiliation: Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Hisayoshi
authors.initials: H
authors.lastname: Hashimoto
authors.affiliation: Department of Experimental Therapeutics, National Cancer Center Hospital, Tokyo, Japan; Division of Cancer Immunotherapy, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center, Tokyo, Japan.
authors.forename: Shigehisa
authors.initials: S
authors.lastname: Kitano
authors.affiliation: Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Shizuka
authors.initials: S
authors.lastname: Yamagata
authors.affiliation: Division of Pathology and Clinical Laboratories, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Miyagi Maeshima
authors.affiliation: Division of Molecular and Cellular Medicine, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Ueda
authors.affiliation: Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Ayumu
authors.initials: A
authors.lastname: Ito
authors.affiliation: Division of Cancer Immunotherapy, Exploratory Oncology Research and Clinical Trial Center, National Cancer Center, Tokyo, Japan; Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Tada
authors.affiliation: Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Fuji
authors.affiliation: Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Center for Cell and Gene Therapy, Takara Bio Inc, Tokyo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tomura
authors.affiliation: Center for Cell and Gene Therapy, Takara Bio Inc, Tokyo, Japan.
authors.forename: Ikuei
authors.initials: I
authors.lastname: Nukaya
authors.affiliation: Center for Cell and Gene Therapy, Takara Bio Inc, Tokyo, Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Mineno
authors.affiliation: Department of Hematopoietic Stem Cell Transplantation, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fukuda
authors.affiliation: Department of Hematology and Oncology, St Luke's International University and Hospital, Tokyo, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Mori
authors.affiliation: Research Planning and Management Department, St Luke's International University and Hospital, Tokyo, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Takaue
authors.affiliation: Immunotherapy and Cell Therapy Service, St Luke's International University and Hospital Tokyo, Japan; Laboratory for Joint Research and Development, St Luke's International University and Hospital, Tokyo, Japan. Electronic address: heiyuji@luke.ac.jp.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Heike
mesh_terms: D005260:Female; D005434:Flow Cytometry; D015774:Ganciclovir / Q000627:therapeutic use; D041722:Genes, Transgenic, Suicide; D015316:Genetic Therapy / Q000379:methods*; D006086:Graft vs Host Disease / Q000188:drug therapy / Q000276:immunology; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007938:Leukemia / Q000628:therapy*; D008875:Middle Aged; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism; D018139:Simplexvirus / Q000235:genetics; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D013937:Thymidine Kinase / Q000235:genetics*; D014019:Tissue Donors
chemical_list: D016693:Receptors, Antigen, T-Cell, alpha-beta; D013937:Thymidine Kinase; D015774:Ganciclovir
keywords: T-cell function; T-cell repertoire; haplo-identical hematopoietic stem cell transplantation; herpes simplex virus thymidine kinase suicide gene; insertional oncogenesis