Clinical scale electroloading of mature dendritic cells with melanoma whole tumor cell lysate is superior to conventional lysate co-incubation in triggering robust in vitro expansion of functional antigen-specific CTL
Highlights
► Generate potent DC in eliciting specific CD8+ T cells. ► Lower tumor lysate amount required for generating potent DC ► Use automated, scalable and closed FDA-approved manufacturing technology.
Introduction
The advantage of DC vaccine has been revealed, especially through the FDA's approval of Dendreon's Provenge. Enhancing further the potency of DC vaccines and perfecting antigen loading procedure are highly demanded. Generally, three ways are used to deliver antigen to DC: peptide pulsing (targeting DC membrane HLA molecules), passive delivery through co-incubation of antigen with immature DC (imDC) to make use of the endogenous endocytosis function of DC, and the active delivery of antigen through transfection/infection methods [1], [2], [3], [4]. Specific or non-specific whole antigens have been used. Loading synthetic mRNA encoding one or a few specific antigens dramatically increasing the antigen concentration inside DC and loading whole molecule antigens derived from synthetic mRNA, tumor whole cell lysates, or tumor cell apoptotic bodies become more favorable [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15]. Active delivery of antigens through transfection of antigen-encoding mRNA demonstrated the efficiency in antigenicity, but the lack of GMP-compliant system with capacity of delivery of large number of cell overburdens the vaccine development/production process, therefore it limits the development of DC vaccine. The comparison study of active [3] and passive deliveries with whole antigens [16], [17], [18] by a GMP-compliant procedure at a clinical scale level is urgently needed to make the full use of the advantage of DC vaccine approach.
In this report, we applied our previous understanding of whole antigen approach in mouse DC study [3] to matured human DC and used a GMP-compliant electroporation-based system with scalable capacity from a fraction of millions of cells to dozens of billions of cells in transfection. We showed that the active delivery was more efficient than passive co-culture delivery, needs less material than passive co-culture delivery, is superior in antigen-specific-CD8-T-cell generation to passive co-culture delivery, and is scalable linearly from 15 million cells to 1 billion of cells, a commonly reported clinical comparable level.
Section snippets
Media and cytokines
Therapeutic grade AIM-V medium was purchased from Invitrogen (Carlsbad, CA, cat. no. 87-0112DK). Research grade recombinant human IL-4 was purchased from CellGenix (Antioch, IL, cat. no. 1403). Clinical grade recombinant human GM-CSF was purchased from Bayer (Leukine®). The following additional cytokines were also used in this study: rhIL-2 (Peprotech, Rocky Hill, NJ, cat. no. 200-02); rhIL-7 (Peprotech, cat. no. 200-07); TNF-α (Peprotech, cat. no. 300-01A); PGE-2 (Sigma-Aldrich, cat. no.
Robust level of M1 protein is detected in melanoma tumor cell lines electroloaded with plasmid DNA encoding influenza virus M1 protein
In clinical practice, autologous tumor cell lysates are frequently used to pulse patients' DCs with tumor antigens. In our studies, to establish proof of concept, we used an allogeneic melanoma tumor cell line, JCOCB, to prepare whole cell lysates and DCs from healthy volunteer donors. This tumor cell line was determined to express abundant MART-1 protein (Fig. 1A). However, previous attempts by others to expand MART-126–35-specific CD8+ T cell populations have met with varying degrees of
Discussion
The focus of this study was to translate our previously reported pre-clinical studies using whole tumor cell lysate-electroloaded murine DCs to develop a robust, efficient and regulatory-compliant process for human clinical and commercial applications. The aims of this study were: [1] to provide proof of concept that loading human DCs with cell lysates using electroporation is superior to the current practice of lysate co-incubation; and [2] to demonstrate that this process is reproducible and
References (28)
- et al.
Cytoplasmic transduction peptide (CTP): new approach for the delivery of biomolecules into cytoplasm in vitro and in vivo
Exp Cell Res
(2006) - et al.
Side-by-side comparison of lentivirally transduced and mRNA-electroporated dendritic cells: implications for cancer immunotherapy protocols
Mol Ther
(2004) - et al.
An improved RNA amplification procedure results in increased yield of autologous RNA transfected dendritic cell-based vaccine
Biochim Biophys Acta
(2005) - et al.
Antigen loading of dendritic cells with whole tumor cell preparations
J Immunol Methods
(2003) - et al.
Early events in dendritic cell maturation induced by LPS
Microbes Infect
(1999) - et al.
Dendritic cells are specialized accessory cells along with TGF- for the differentiation of Foxp3+ CD4+ regulatory T cells from peripheral Foxp3 precursors
Blood
(2007) - et al.
Indoleamine 2,3-dioxygenase-expressing mature human monocyte-derived dendritic cells expand potent autologous regulatory T cells
Blood
(2009) - et al.
Noncanonical NF-kappaB signaling in dendritic cells is required for indoleamine 2,3-dioxygenase (IDO) induction and immune regulation
Blood
(2007) - et al.
Dendritic cells transduced with tumor-associated antigen gene elicit potent therapeutic antitumor immunity: comparison with immunodominant peptide-pulsed DCs
Oncology
(2005) - et al.
Immunodominance across HLA polymorphism: implications for cancer immunotherapy
J Immunother
(1998)
Efficient responses in a murine renal tumor model by electroloading dendritic cells with whole-tumor lysate
J Immunother
Messenger RNA-electroporated dendritic cells presenting MAGE-A3 simultaneously in HLA class I and class II molecules
J Immunol
Electroporation of immature and mature dendritic cells: implications for dendritic cell-based vaccines
Gene Ther
Highly efficient gene delivery by mRNA electroporation in human hematopoietic cells: superiority to lipofection and passive pulsing of mRNA and to electroporation of plasmid cDNA for tumor antigen loading of dendritic cells
Blood
Cited by (0)
- 1
Co-first authors/these authors contributed equally.
- 2
Current address: Amplimmune, Inc., Rockville, MD, 20850, USA.