Efficient lysis of epithelial ovarian cancer cells by MAGE-A3-induced cytotoxic T lymphocytes using rAAV-6 capsid mutant vector

Vaccine. 2014 Feb 12;32(8):938-43. doi: 10.1016/j.vaccine.2013.12.049. Epub 2014 Jan 6.

Abstract

MAGE-A3 is highly expressed in epithelial ovarian cancer (EOC), making it a promising candidate for immunotherapy. We investigated whether dendritic cells (DCs) transduced with a rAAV-6 capsid mutant vector Y445F could elicit effective MAGE-A3-specific anti-tumor cytotoxic T lymphocyte (CTL) responses in vitro. MAGE-A3 was cloned and rAAV-6-MAGE-A3 purified, followed by proviral genome detection using real-time PCR. Immunofluorescence detection of rAAV-6-Y445F-MAGE-A3-transduced DCs demonstrated 60% transduction efficiency. Fluorescent in situ hybridization analysis confirmed chromosomal integration of rAAV vectors. Flow cytometric analysis of transduced DCs showed unaltered expression of critical monocyte-derived surface molecules with retention of allo-stimulatory activity. Co-culture of autologous T lymphocytes with MAGE-A3-expressing DCs produced CTLs that secreted IFN-γ, and efficiently killed MAGE-A3+ EOC cells. This form of rAAV-based DC immunotherapy, either alone or more likely in combination with other immune-enhancing protocols, may prove useful in the clinical setting for management of EOC.

Keywords: Adeno-associated Virus 6; Capsid tyrosine mutant; Cytotoxic T lymphocytes; Dendritic cells; Epithelial ovarian cancer; MAGE-A3.

MeSH terms

  • Antigens, Neoplasm / immunology*
  • Capsid
  • Carcinoma, Ovarian Epithelial
  • Cell Line, Tumor
  • Dendritic Cells / cytology
  • Dendritic Cells / immunology
  • Dependovirus / genetics
  • Genetic Vectors
  • Humans
  • Immunotherapy*
  • Interferon-gamma / immunology
  • Lymphocyte Culture Test, Mixed
  • Mutation
  • Neoplasm Proteins / immunology*
  • Neoplasms, Glandular and Epithelial / pathology*
  • Ovarian Neoplasms / pathology*
  • T-Lymphocytes, Cytotoxic / immunology*
  • Transduction, Genetic

Substances

  • Antigens, Neoplasm
  • MAGEA3 protein, human
  • Neoplasm Proteins
  • Interferon-gamma