title: Immunization with aspartate-β-hydroxylase-loaded dendritic cells produces antitumor effects in a rat model of intrahepatic cholangiocarcinoma.
abstract: Dendritic cells (DCs) capture and process proteins and present peptides on the cell surface in the context of major histocompatibility complex I and II molecules to induce antigen-specific T cell immune responses. The aims of this study were to (1) employ an expanded and purified DC population and load them with aspartate-β-hydroxylase (ASPH), a highly expressed tumor-associated cell surface protein, and (2) to determine if immunization induced antitumor effects in an orthotopic rat model of intrahepatic cholangiocarcinoma. Splenocytes were incubated with ASPH-coated beads and passed through a magnetic field to yield an 80% pure DC OX62+ population. This DC subset was stimulated with granulocyte-macrophage colony-stimulating factor, interleukin-4, CD40L, and interferon-γ, resulting in a 40-fold increase in interleukin-12A messenger RNA expression to subsequently generate a T helper 1-type immune response. After incubation with the cytokine cocktail, DCs were found to have matured, as demonstrated by increased expression of CD40, CD80, and CD86 costimulatory molecules. Immunization with ASPH-loaded DCs induced antigen-specific immunity. A clone of the parental tumorigenic rat BDEneu cholangiocyte cell line, designated BDEneu-CL24, was found to have the highest number of cells expressing this surface protein (97%); it maintained the same phenotypic characteristics of the parental cell line and was used to produce intrahepatic tumors in immunocompetent syngeneic Fisher-344 rats. Immunization with ASPH-loaded DCs generated cytotoxicity against cholangiocarcinoma cells in vitro and significantly suppressed intrahepatic tumor growth and metastasis, and was associated with increased CD3+ lymphocyte infiltration into the tumors.
  
  
  CONCLUSIONS
  These findings suggest that immunization with ASPH-loaded DCs may constitute a novel therapeutic approach for intrahepatic cholangiocarcinoma, because this protein also appears to be highly conserved and expressed on human hepatobiliary tumors.
authors: The Liver Research Center, Department of Medicine, Rhode Island Hospital and Brown Medical School, Providence, RI 02903, USA.
authors: Takehiro
authors: T
authors: Noda
authors: Masafumi
authors: M
authors: Shimoda
authors: Vivian
authors: V
authors: Ortiz
authors: Alphonse E
authors: AE
authors: Sirica
authors: Jack R
authors: JR
authors: Wands
mesh_terms: D019264:Adoptive Transfer / Q000379:methods*; D000818:Animals; D001216:Asparagine / Q000031:analogs & derivatives* / Q000235:genetics / Q000276:immunology; D001650:Bile Duct Neoplasms / Q000276:immunology / Q000628:therapy*; D001653:Bile Ducts, Intrahepatic; D002455:Cell Division / Q000276:immunology; D002478:Cells, Cultured; D018281:Cholangiocarcinoma / Q000276:immunology / Q000628:therapy*; D003713:Dendritic Cells / Q000166:cytology / Q000201:enzymology / Q000276:immunology*; D004195:Disease Models, Animal; D006801:Humans; D007114:Immunization / Q000379:methods; D018664:Interleukin-12 / Q000276:immunology / Q000378:metabolism; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D011994:Recombinant Proteins; D018664:Interleukin-12; C024848:beta-aspartylhydroxamic acid; D001216:Asparagine