1. Significant anti-tumour activity of adoptively transferred T cells elicited by intratumoral dendritic cell vaccine injection through enhancing the ratio of CD8+ T cell/regulatory T cells in tumour
- Author
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Kai-xia Zhang, Hong-yu You, C Yan, Z Wang, Fuying Liu, Shu-xia Song, and Jingmiao Wang
- Subjects
Adoptive cell transfer ,Time Factors ,Translational Studies ,medicine.medical_treatment ,T cell ,T-Lymphocytes ,Immunology ,CD4-CD8 Ratio ,Melanoma, Experimental ,CD8-Positive T-Lymphocytes ,Cancer Vaccines ,Immunotherapy, Adoptive ,T-Lymphocytes, Regulatory ,Interleukin-7 Receptor alpha Subunit ,Interleukin 21 ,Interferon-gamma ,Mice ,Immune system ,Cell Line, Tumor ,medicine ,Immunology and Allergy ,Cytotoxic T cell ,Animals ,Antigen-presenting cell ,business.industry ,Vaccination ,Dendritic cell ,Immunotherapy ,Dendritic Cells ,Combined Modality Therapy ,Hepatitis B Core Antigens ,Mice, Inbred C57BL ,medicine.anatomical_structure ,business ,Dinucleoside Phosphates - Abstract
Summary We have shown that immunization with dendritic cells (DCs) pulsed with hepatitis B virus core antigen virus-like particles (HBc-VLP) packaging with cytosine–guanine dinucleotide (CpG) (HBc-VLP/CpG) alone were able to delay melanoma growth but not able to eradicate the established tumour in mice. We tested whether, by modulating the vaccination approaches and injection times, the anti-tumour activity could be enhanced. We used a B16-HBc melanoma murine model not only to compare the efficacy of DC vaccine immunized via footpads, intravenously or via intratumoral injections in treating melanoma and priming tumour-specific immune responses, but also to observe how DC vaccination could improve the efficacy of adoptively transferred T cells to induce an enhanced anti-tumour immune response. Our results indicate that, although all vaccination approaches were able to protect mice from developing melanoma, only three intratumoral injections of DCs could induce a significant anti-tumour response. Furthermore, the combination of intratumoral DC vaccination and adoptive T cell transfer led to a more robust anti-tumour response than the use of each treatment individually by increasing CD8+ T cells or the ratio of CD8+ T cell/regulatory T cells in the tumour site. Moreover, the combination vaccination induced tumour-specific immune responses that led to tumour regression and protected surviving mice from tumour rechallenge, which is attributed to an increase in CD127-expressing and interferon-γ-producing CD8+ T cells. Taken together, these results indicate that repeated intratumoral DC vaccination not only induces expansion of antigen-specific T cells against tumour-associated antigens in tumour sites, but also leads to elimination of pre-established tumours, supporting this combined approach as a potent strategy for DC-based cancer immunotherapy.
- Published
- 2010