title: [Cloning, expression and antitumor effect of mouse costimulatory molecule 4-1BBL].
abstract: OBJECTIVE
  To clone mouse 4-1BBL gene, construct its eukaryotic expression vector, and evaluate antitumor activity of the expression product.
  
  
  METHODS
  RT-PCR was used to amplify mouse 4-1BBL gene from total RNA of C57BL/6 splenocytes stimulated by PHA. Then m4-1BBL cDNA was subcloned into eukaryotic expression vector pcDNA3.1(+) and transfected into mouse hepatocellular carcinoma cell line Hepa1-6. The expression of m4-1BBL in transfected cells was detected by RT-PCR, indirect immunofluorescence staining, and flow cytometry. Non-adherent splenocytes from non-immunized C57BL/6 mice were incubated with mitomycin-treated non-transfected Hepa1-6(Hepa1-6-wt) or transfected Hepa1-6 cells (Hepal-6-m4-1BBL), respectively. Then the lymphocytes were tested for cytotoxic activity to Hepa1-6-wt cells.
  
  
  RESULTS
  The Hepa1-6 cells transfected by pcDNA3.1(+)-m4-1BBL could efficiently express m4-1BBL. As compared with Hepa1-6-wt cells,Hepa1-6-m4-1BBL cells could induce more efficiently cytotoxic activity of lymphocytes to Hepa1-6-wt cells (P<0.01).
  
  
  CONCLUSIONS
  The expression of m4-1BBL by tumor cells is effective in inducing antitumor immune response.
authors.affiliation: Department of Hepatobiliary Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Cheng-li
authors.initials: CL
authors.lastname: Liu
authors.forename: Ke-feng
authors.initials: KF
authors.lastname: Dou
authors.forename: Bang-fu
authors.initials: BF
authors.lastname: Zhu
authors.forename: Xiao-xia
authors.initials: XX
authors.lastname: Zang
authors.forename: Yu-bo
authors.initials: YB
authors.lastname: Chai
authors.forename: Ke-jun
authors.initials: KJ
authors.lastname: Du
authors.forename: Su-min
authors.initials: SM
authors.lastname: Chen
mesh_terms: D053330:4-1BB Ligand; D000818:Animals; D019496:Cancer Vaccines / Q000276:immunology; D003001:Cloning, Molecular; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000276:immunology*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000235:genetics* / Q000502:physiology
chemical_list: D053330:4-1BB Ligand; D019496:Cancer Vaccines; D012333:RNA, Messenger; C505975:Tnfsf9 protein, mouse; D014409:Tumor Necrosis Factor-alpha