title: Bacillus Calmette-Guérin cell-wall skeleton enhances the killing activity of cytotoxic lymphocyte-activated human dendritic cells transduced with the prostate-specific antigen gene.
abstract: To determine whether dendritic cells (DC) transduced with the prostate-specific antigen (PSA) gene can induce PSA-specific cytotoxic lymphocytes (CTL) against prostate cancer cells, and whether bacillus Calmette-Guérin (BCG) cell-wall skeleton (CWS) can enhance the maturation of DC-PSA and the killing activity of subsequently induced PSA-specific CTL. MATERIALS AND METHODS; We generated an adenovirus encoding the PSA gene (AxCA-PSA) using the cosmid-terminal protein complex method. DC were infected with AxCA-PSA using the centrifugal method. The ability of CTL to lyse target cells expressing PSA, i.e the PSA-positive prostate cancer cell line, LNCap, and PSA-transduced autologous phytohaemagglutinin (PHA) blasts expressing PSA, was assessed using the 51Cr-release assay. The maturation of DC-PSA stimulated by BCG-CWS was assayed by flow cytometry. The cytotoxic activity enhanced by BCG-CWS was assessed by the 51Cr-release assay.
  
  
  RESULTS
  DC-PSA induced PSA-specific CTL with 85% cytotoxic activity against LNCaP (effector: target ratio, E:T, of 50:1). However, the cytotoxic activity against PSA-negative cells was very low. Anti-CD8 and anti-major histocompatibility (MHC) class I antibodies blocked PSA-specific cytotoxicity. The PSA-specific killing was reproducible against autologous PHA blast cells expressing PSA, independently of human leukocyte antigen haplotype. Furthermore, the combination of DC-PSA with BCG-CWS remarkably enhanced the PSA-specific cytotoxicity against PHA blasts expressing PSA (15-30% at an E:T ratio of 50:1).
  
  
  CONCLUSIONS
  These findings suggest that DC-PSA can induce MHC class I-restricted PSA-specific CD8+ CTL responses and that DC-PSA matured by BCG-CWS enhance PSA-specific cytotoxicity. The combination of DC-PSA with BCG-CWS might be a useful approach for treating advanced prostate cancer.
authors.affiliation: Departments of Urology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Reona
authors.initials: R
authors.lastname: Fujii
authors.forename: Makoto
authors.initials: M
authors.lastname: Iwahashi
authors.forename: Kazuro
authors.initials: K
authors.lastname: Kikkawa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Inagaki
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kohjimoto
authors.forename: Toshiyasu
authors.initials: T
authors.lastname: Ojima
authors.forename: Takashi
authors.initials: T
authors.lastname: Mori
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kuramoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nishizawa
authors.forename: Ichiro
authors.initials: I
authors.lastname: Azuma
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamaue
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Shinka
authors.forename: Isao
authors.initials: I
authors.lastname: Hara
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D016827:CD8 Antigens / Q000276:immunology; D045744:Cell Line, Tumor; D017358:Cell Wall Skeleton / Q000276:immunology / Q000494:pharmacology*; D003713:Dendritic Cells / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D008297:Male; D009163:Mycobacterium bovis; D017430:Prostate-Specific Antigen / Q000235:genetics*; D011471:Prostatic Neoplasms / Q000628:therapy*; D013602:T-Lymphocytes, Cytotoxic / Q000502:physiology*; D014161:Transduction, Genetic
chemical_list: D016827:CD8 Antigens; D017358:Cell Wall Skeleton; D015395:Histocompatibility Antigens Class I; D017430:Prostate-Specific Antigen