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- Fotaki, Grammatiki, et al.
(författare)
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Cancer vaccine based on a combination of an infection-enhanced adenoviral vector and pro-inflammatory allogeneic DCs leads to sustained antigen-specific immune responses in three melanoma models
- 2018
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Ingår i: Oncoimmunology. - 2162-4011 .- 2162-402X. ; 7:3
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Tidskriftsartikel (refereegranskat)abstract
- Autologous patient-derived dendritic cells (DCs) modified ex vivo to present tumor-associated antigens (TAAs) are frequently used as cancer vaccines. However, apart from the stringent logistics in producing DCs on a patient basis, accumulating evidence indicate that ex vivo engineered DCs are poor in migration and in fact do not directly present TAA epitopes to naïve T cells in vivo. Instead, it is proposed that bystander host DCs take up material from vaccine-DCs, migrate and subsequently initiate antitumor T-cell responses. We used mouse models to examine the possibility of using pro-inflammatory allogeneic DCs (alloDCs) to activate host DCs and enable them to promote antigen-specific T-cell immunity. We found that alloDCs were able to initiate host DC activation and migration to draining lymph node leading to T-cell activation. The pro-inflammatory milieu created by alloDCs also led to recruitment of NK cells and neutrophils at the site of injection. Vaccination with alloDCs combined with Ad5M(gp100), an infection-enhanced adenovirus encoding the human melanoma-associated antigen gp100 resulted in generation of CD8+ T cells with a T-cell receptor (TCR) specific for the gp10025-33 epitope (gp100-TCR+). Ad5M(gp100)-alloDC vaccination in combination with transfer of gp100-specific pmel-1 T cells resulted in prolonged survival of B16-F10 melanoma-bearing mice and altered the composition of the tumor microenvironment (TME). We hereby propose that alloDCs together with TAA- or neoepitope-encoding Ad5M can become an “off-the-shelf” cancer vaccine, which can reverse the TME-induced immunosuppression and induce host cellular anti-tumor immune responses in patients without the need of a time-consuming preparation step of autologous DCs.
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2. |
- Fotaki, Grammatiki, et al.
(författare)
-
Pro-inflammatory allogeneic DCs promote activation of bystander immune cells and thereby license antigen-specific T-cell responses
- 2018
-
Ingår i: Oncoimmunology. - 2162-4011 .- 2162-402X. ; 7:3
-
Tidskriftsartikel (refereegranskat)abstract
- Accumulating evidence support an important role for endogenous bystander dendritic cells (DCs) in the efficiency of autologous patient-derived DC-vaccines, as bystander DCs take up material from vaccine-DCs, migrate to draining lymph node and initiate antitumor T-cell responses. We examined the possibility of using allogeneic DCs as vaccine-DCs to activate bystander immune cells and promote antigen-specific T-cell responses. We demonstrate that human DCs matured with polyI:C, R848 and IFN-γ (denoted COMBIG) in combination with an infection-enhanced adenovirus vector (denoted Ad5M) exhibit a pro-inflammatory state. COMBIG/Ad5M-matured allogeneic DCs (alloDCs) efficiently activated T-cells and NK-cells in allogeneic co-culture experiments. The secretion of immunostimulatory factors during the co-culture promoted the maturation of bystander-DCs, which efficiently cross-presented a model-antigen to activate antigen-specific CD8+ T-cells in vitro. We propose that alloDCs, in combination with Ad5M as loading vehicle, may be a cost-effective and logistically simplified DC vaccination strategy to induce anti-tumor immune responses in cancer patients.
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