title: Listeria Monocytogenes Activated Dendritic Cell Based Vaccine for Prevention of Experimental Tumor in Mice
abstract: The use of dendritic cells (DCs) as a cellular adjuvant provides a promising approach in immunotherapy of cancer. It has been demonstrated that Listeria monocytogenes activated DCs pulsed ex vivo with tumor antigens trigger a systemic Th1-biased specific immune response and a single dose of this vaccine will cause a considerable anti tumor immunity.
  
  
  
  The present study was designed to evaluate the ability of multiple doses of tumor antigen-pulsed DCs, matured in the presence of Listeria monocytogenes components in induction of a potent anti-tumor response and the prevention of tumor formation in an experimental model.
  
  
  
  Bone-marrow derived DCs (BMDCs) were cultured in the presence of GM-CSF and IL-4. After 5 days, tumor lysates with/without Listeria monocytogenes lysate were added to the culture media for another 2 days. Mice received mature and tumor antigen pulsed dendritic cells subcutaneously in 3 groups. Tumor growth was monitored and two weeks after immunotherapy, cytotoxic activity of CD8+ T cells was evaluated in different groups.
  
  
  
  According to the findings, repeated doses of vaccine did not lead to a significant increase in the activity of cytotoxic T cells and decreased tumor growth of immunized animals.
  
  
  
  The current study suggests that increased doses of vaccine do not have sufficient efficiency for prevention of tumor induction. Generation of T regulatory responses upon repeated doses of such vaccines should be considered in future investigations.
authors.affiliation: Department of Immunology, School of Medicine, Medical Sciences/University of Tehran, Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Khamisabadi
authors.forename: Samaneh
authors.initials: S
authors.lastname: Arab
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Motamedi
authors.forename: Nematollah
authors.initials: N
authors.lastname: Khansari
authors.forename: Seied Mohammad
authors.initials: SM
authors.lastname: Moazzeni
authors.forename: Zahra
authors.initials: Z
authors.lastname: Gheflati
authors.forename: Jamshid
authors.initials: J
authors.lastname: Hadjati
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D000951:Antigens, Neoplasm / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000276:immunology*; D045744:Cell Line, Tumor; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology / Q000382:microbiology; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D016219:Immunotherapy, Adoptive; D008089:Listeria monocytogenes; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D009374:Neoplasms, Experimental / Q000276:immunology* / Q000517:prevention & control*
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines