RNA Loading of Leukemic Antigens into Cord Blood–Derived Dendritic Cells for Immunotherapy

• Published in: Biology of blood and marrow transplantation Vol. 12; no. 8; pp. 855 - 867
• Main Authors: Hsu, Andy K.W., Kerr, Beverley M., Jones, Kathryn L., Lock, Richard B., Hart, Derek N.J., Rice, Alison M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2006
• Subjects: Animals; Antigen Presentation - genetics; Antigen Presentation - immunology; Antigens, Neoplasm - genetics; Antigens, Neoplasm - immunology; Cell Line, Tumor; Cytotoxic T lymphocyte; Dendritic cells; Dendritic Cells - cytology; Dendritic Cells - immunology; Electroporation; Electroporation - methods; Fetal Blood - cytology; Fetal Blood - immunology; Humans; Immunotherapy; Immunotherapy - methods; Lymphocyte Activation - genetics; Lymphocyte Activation - immunology; Mice; Neoplasm Transplantation - methods; Neoplasms, Experimental - genetics; Neoplasms, Experimental - immunology; Neoplasms, Experimental - therapy; Precursor Cell Lymphoblastic Leukemia-Lymphoma - genetics; Precursor Cell Lymphoblastic Leukemia-Lymphoma - immunology; Precursor Cell Lymphoblastic Leukemia-Lymphoma - therapy; RNA, Neoplasm - genetics; RNA, Neoplasm - immunology; RNA, Neoplasm - isolation & purification; T-Lymphocytes, Cytotoxic - cytology; T-Lymphocytes, Cytotoxic - immunology; Transplantation, Heterologous; Electroporation; Dendritic cells; Cytotoxic T lymphocyte; Immunotherapy
• ISSN: 1083-8791; 1523-6536
• DOI: 10.1016/j.bbmt.2006.05.004

The manipulation of dendritic cells (DCs) ex vivo to present tumor-associated antigens for the activation and expansion of tumor-specific cytotoxic T lymphocytes (CTLs) attempts to exploit these cells’ pivotal role in immunity. However, significant improvements are needed if this approach is to have wider clinical application. We optimized a gene delivery protocol via electroporation for cord blood (CB) CD34 + DCs using in vitro–transcribed (IVT) mRNA. We achieved > 90% transfection of DCs with IVT-enhanced green fluorescent protein mRNA with > 90% viability. Electroporation of IVT-mRNA up-regulated DC costimulatory molecules. DC processing and presentation of mRNA-encoded proteins, as major histocompatibility complex/peptide complexes, was established by CTL assays using transfected DCs as targets. Along with this, we also generated specific antileukemic CTLs using DCs electroporated with total RNA from the Nalm-6 leukemic cell line and an acute lymphocytic leukemia xenograft. This significant improvement in DC transfection represents an important step forward in the development of immunotherapy protocols for the treatment of malignancy.