Enhanced Dendritic Cell Antigen Presentation in RNA-Based Immunotherapy

doi:10.1006/jsre.2002.6435

Journal of Surgical Research

Volume 105, Issue 1, 1 June 2002, Pages 17-24

Presented at the Annual Meeting of the Association for Academic Surgery, Milwaukee, Wisconsin, November 15–17, 2001

https://doi.org/10.1006/jsre.2002.6435 Get rights and content

Abstract

Background. Dendritic cells pulsed with mRNA provide a unique approach to tumor immunotherapy. We hypothesized that increased mRNA transfection efficiency and dendritic cell maturation would improve antigen processing and presentation as well as T-cell costimulation, resulting in enhanced induction of antimelanoma immune responses.

Methods. Immature monocyte-derived dendritic cells were transfected with mRNA by passive pulsing, lipofection, or electroporation. Dendritic cells were either left untreated or matured using the double-stranded RNA poly(I:C). T-Cell cultures were generated by stimulation of naı̈ve T-cells with each set of dendritic cells. Specific antigen presentation and specific effector T-cell generation were analyzed by an IFN-γ release Elispot assay.

Results. Greatest intracellular green fluorescent protein was observed by flow cytometry following dendritic cell electroporation with green fluorescent protein mRNA. DC presentation of Mart-1/Melan A peptide, as measured by Elispot assay using a specific T-cell clone, was greatest following transfection with Mart-1/Melan A mRNA by electroporation. Maturation of dendritic cells further improved antigen presentation regardless of transfection technique. Specific Mart-1/Melan A effector T cells were produced after culture of naı̈ve T cells with dendritic cells that were electroporated with Mart-1/Melan A mRNA and then matured, but not for dendritic cells that remained immature.

Conclusions. Efficient mRNA transfection by electroporation as well as dendritic cell maturation results in increased levels of Mart-1/Melan A antigen presentation and enhanced production of antigen-specific effector T cells. This combination of strategies may be used to enhance immune responses to RNA-based dendritic cell vaccines.

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Electroporation with mRNA has been explored elaborately in dendritic cells (DCs) because of their possible use in vaccination strategies (see the discussion later). Loading DCs with mRNA encoding different tumor associated antigens (TAAs) proved to be efficient, transfecting up to 50% of treated cells [86,87]. The transfection efficiencies reported by Bontkes et al. were even higher (up to 75%) [88].
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^☆: M.F.K. and M.W.O. contributed equally to this article.

¹: Supported by a National Research Service Award.

²: Supported by a Lustgarten Foundation Grant.

³: To whom correspondence should be addressed. Fax: (919) 684-8060. E-mail: [email protected].

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Regular ArticleEnhanced Dendritic Cell Antigen Presentation in RNA-Based Immunotherapy☆

Abstract

Curr. Opin. Immunol.

Hum. Immunol.

Blood

Blood

J. Immunol. Methods

Immunol. Lett.

J. Immunol. Methods

Blood

Blood

Dendritic cells and the control of immunity

Nature

The dendritic cell system and its role in immunogenicity

Annu. Rev. Immunol.

Vaccination of melanoma patients with peptide- or tumor lysate-pulsed dendritic cells

Nat. Med.

Vaccination of patients with B-cell lymphoma using autologous antigen-pulsed dendritic cells

Nat. Med.

Immunotherapy of cancer with dendritic-cell-based vaccines

Cancer Immunol. Immunother.

Human dendritic cells transfected with RNA encoding prostate-specific antigen stimulate prostate-specific CTL responses in vitro

J. Immunol.

Induction of primary carcinoembryonic antigen (CEA)-specific cytotoxic T lymphocytes using human dendritic cells transfected with RNA

Nat. Biotechnol.

Clonal expansion versus functional clonal inactivation: a costimulatory signalling pathway determines the outcome of T cell antigen receptor capacity

Annu. Rev. Immunol.

T cell activation determined by T cell receptor number and tunable thresholds

Science

Dendritic cells pulsed with RNA are potent antigen-presenting cells in vitro and in vivo

J. Exp. Med.

Delivery of liposome-encapsulated HIV type 1 proteins to human dendritic cells for stimulation of HIV type 1-specific memory cytotoxic T lymphocyte responses

AIDS Res. Hum. Retroviruses

Optimization of methods to achieve mRNA-mediated transfection of tumor cells in vitro and in vivo employing cationic liposome vectors

Cancer Gene Ther.

Regular Article
Enhanced Dendritic Cell Antigen Presentation in RNA-Based Immunotherapy☆