title: [Dendritic cells infected by recombinant adeno-associated virus with CEA gene to induce antigen-specific CTL response to CD44(+)CD24(-/low) cells from MCF-7 breast cancer cell line].
abstract: OBJECTIVE
  To infect dendritic cells (DC) by recombinant human adeno-associated virus (rh-AAV) vector with CEA gene to generate antigen-specific CTL cells in vitro and to assay the CEA specific cytotoxic T lymphocyte(CTL), response to CD44(+)CD24(-/low) breast cancer stem cells.
  
  
  METHODS
  Peripheral blood mononuclear cells were induced to generate DCs by cytokines interleukin-4(IL-4), granulocyte-macrophage colony-stimulating factor(GM-CSF)and tumor necrosis factor-alpha(TNF-α) while T lymphocytes were cultured with cytokines interleukin-2(IL-2). DCs were infected by CEA gene containing rh-AAV. After being matured, DCs were co-cultured with T cells to generate CTL cells. CD44(+)CD24(-/low) breast cancer stem cells were sorted out from MCF-7 and MDA-MB-231 cells. CEA specific CTL response to CD44(+)CD24(-/low) breast cancer stem cells was assayed by MTT method.
  
  
  RESULTS
  The percentages of CD44(+)CD24(-/low) breast cancer stem cells subsets in MCF-7 and MDA-MB-231 were 5.1% and 76.3% respectively. DCs transfected with CEA gene could induce CEA antigen CTLs response. The killing ratio of MCF-7 cells in CEA gene transfection group was 46.5% plusmn; 15.0% with significant difference (P=0.009) as compared with that of CEA gene untransfection group. As for CD44(+)CD24(-/low) breast cancer stem cells subset from MCF-7 cells, CEA gene transfection group resulted in a higher killing ratio of 44.7% ± 28.2% as compared with that of CEA untransfection group. While the inhibitory rate of non-breast cancer stem cells subset from MCF-7 cells in CEA gene transfection group was 50.6% ± 22.2% (P=0.05). CTL cells generated by DCs transfected with CEA gene did not show inhibitory activity to MDA-MB-231 breast cancer cells (without CEA expression) as compared with CEA gene untransfection group. It was the same in CD44(+)CD24(-/low) breast cancer stem cells subset and non-breast cancer stem cells subset from MDA-MB-231 breast cancer cells (P>0.05).
  
  
  CONCLUSIONS
  DCs infected by rh-AAV with CEA gene could induce antigen-specific CTL response to kill CEA expressing breast cancer cells involved in CD44(+)CD24(-/low) breast cancer stem cells subset. It suggests that immune therapy might be a potential treatment of breast cancer stem cells.
authors.affiliation: Peking University School of Oncology, Beijing Cancer Hospital, Beijing 100142, China.
authors.forename: Xiao-li
authors.initials: XL
authors.lastname: Wang
authors.forename: Bo
authors.initials: B
authors.lastname: Ma
authors.forename: Jun
authors.initials: J
authors.lastname: Jia
authors.forename: Yan-hua
authors.initials: YH
authors.lastname: Yuan
authors.forename: Ying
authors.initials: Y
authors.lastname: Yan
authors.forename: Li-jun
authors.initials: LJ
authors.lastname: Di
authors.forename: Guo-hong
authors.initials: GH
authors.lastname: Song
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Jun
authors.initials: J
authors.lastname: Ren
mesh_terms: D001943:Breast Neoplasms / Q000276:immunology / Q000473:pathology*; D051927:CD24 Antigen / Q000378:metabolism; D002272:Carcinoembryonic Antigen / Q000096:biosynthesis / Q000235:genetics*; D045744:Cell Line, Tumor; D003713:Dendritic Cells / Q000276:immunology*; D000229:Dependovirus / Q000235:genetics*; D005260:Female; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection
chemical_list: D051927:CD24 Antigen; D002272:Carcinoembryonic Antigen; D018960:Hyaluronan Receptors; D011993:Recombinant Fusion Proteins