Generation of dendritic cell-tumor cell hybrids by electrofusion for clinical vaccine application

• Published in: Cancer Immunology, Immunotherapy Vol. 53; no. 8; pp. 705 - 714
• Main Authors: TREVOR, Katrina T, COVER, Cathleen, RUIZ, Yvette W, AKPORIAYE, Emmanuel T, HERSH, Evan M, LANDAIS, Didier, TAYLOR, Rachel R, KING, Alan D, WALTERS, Richard E
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.08.2004; Springer Nature B.V; Springer-Verlag
• Subjects: Antigen Presentation; Antigen-Presenting Cells - immunology; Antigen-Presenting Cells - metabolism; Antigens, Neoplasm - immunology; Antigens, Neoplasm - metabolism; Antineoplastic agents; Biological and medical sciences; Cancer Vaccines - therapeutic use; CD8-Positive T-Lymphocytes - immunology; CD8-Positive T-Lymphocytes - metabolism; Cell Fusion; Cell Survival - immunology; Dendritic Cells - immunology; Dendritic Cells - metabolism; Electric Stimulation; gp100 Melanoma Antigen; HLA-A Antigens - immunology; HLA-A Antigens - metabolism; HLA-A2 Antigen; Humans; Hybrid Cells; Medical sciences; Membrane Glycoproteins - immunology; Membrane Glycoproteins - metabolism; Neoplasm Proteins - immunology; Neoplasm Proteins - metabolism; Neoplasms - immunology; Neoplasms - metabolism; Neoplasms - therapy; Original; Pharmacology. Drug treatments; T-Lymphocytes, Cytotoxic - immunology; Tumor Cells, Cultured - immunology; Tumor Cells, Cultured - metabolism; Tumors; Dendritic cell; Hybrids; Hybrid cell; Dendritic cells; Electrofusion; Antigen presenting cell; Immunotherapy; Vaccine; Tumor cell; Cancer
• ISSN: 0340-7004; 1432-0851
• DOI: 10.1007/s00262-004-0512-1

Vaccination with hybrids comprising fused dendritic cells (DCs) and tumor cells is a novel cancer immunotherapy approach designed to combine tumor antigenicity with the antigen-presenting and immune-stimulatory capacities of DCs. For clinical purposes, we have incorporated a large-scale process for the generation of clinical-grade DCs together with novel electrofusion technology. The electrofusion system provides for ease and standardization of method, efficient DC-tumor cell hybrid formation, and large-quantity production of hybrids in a high-volume (6-ml) electrofusion chamber. In addition, we have evaluated DC electrofusion with a variety of allogeneic human tumor cell lines with the rationale that these tumor cell partners would prove a ready, suitable source for the generation of DC-tumor cell hybrid vaccines. The DC production process can generate 6x10(8) to 2x10(9) DCs from a single leukapheresis product (approximately 180 ml). As determined by FACS analysis, electrofusion of 6x10(7) total cells (1:1 ratio of DC and tumor cells) resulted in a consistent average of 8-10% DC-tumor cell hybrids, irrespective of the tumor type used. Hybrids were retained in the population for 48 h postfusion and following freezing and thawing. Upon pre-irradiation of the tumor cell partner for vaccine purposes, the overall fusion efficiency was not altered at doses up to 200 Gy. Evaluation of DC-tumor cell hybrid populations for their ability to stimulate T-cell responses demonstrated that electrofused populations are superior to mixed populations of DCs and tumor cells in generating a primary T-cell response, as indicated by IFN-gamma release. Moreover, hybrids comprising HLA-A*0201 DCs and allogeneic melanoma tumor cells (Colo 829 cell line) stimulated IFN-gamma secretion by antigen-specific CD8+ T cells, which are restricted for recognition of a melanoma gp100 peptide antigen (gp100(209-217)) within the context of the DC HLA haplotype. Maturation of the DC-Colo 829 cell hybrid population served to further improve this T-cell gp100-specific response. Overall, our results are promising for the large-scale generation of electrofused hybrids comprising DCs and allogeneic tumor cells, that may prove useful in human vaccine trials.