Pyroptosis is a recently discovered form of inflammatory programmed necrosis characterized by caspase1-mediated and gasdermin D-dependent cell death leading to the release of pro-inflammatory... Show morePyroptosis is a recently discovered form of inflammatory programmed necrosis characterized by caspase1-mediated and gasdermin D-dependent cell death leading to the release of pro-inflammatory cytokines such as Interleukin-1 beta (IL-18). Here, we evaluated whether pyroptosis could be exploited in DNA vaccination by incorporating a constitutively active variant of caspase-1 to the antigen-expressing DNA. In vitro, transfection with constitutively active caspase-1 DNA induced pro-IL-18 maturation and IL-18 release as well as gasdermin D-dependent cell death. To test active caspase-1 as a genetic adjuvant for the induction of antigen-specific T cell responses, mice were vaccinated intradermally with a DNA vaccine consisting of the active caspase-1 plasmid together with a plasmid encoding an ovalbuminderived CD8 T cell epitope. Active caspase-1 accelerated and amplified antigen-specific CD8 T cell responses when administered simultaneously with the DNA vaccine at an equimolar dose. Moreover, upon challenge with melanoma cells expressing ovalbumin, mice vaccinated with the antigen vaccine adjuvanted with active caspase-1 showed significantly better survival compared to the non-adjuvanted group. In conclusion, we have developed a novel genetic adjuvant that for the first time employs the pyroptosis pathway to improve DNA vaccination against cancer. (c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/). Show less
Pardieck, I.N.; Duikeren, S. van; Veerkamp, D.M.B.; Brasem, D.J.; Redeker, A.; Bergen, J. van; ... ; Arens, R. 2022
Human cytomegalovirus (HCMV) is an ubiquitous herpesvirus that can cause serious morbidity and mortality in immunocompromised or immune-immature individuals. A vaccine that induces immunity to CMV... Show moreHuman cytomegalovirus (HCMV) is an ubiquitous herpesvirus that can cause serious morbidity and mortality in immunocompromised or immune-immature individuals. A vaccine that induces immunity to CMV in these target populations is therefore highly needed. Previous attempts to generate efficacious CMV vaccines primarily focused on the induction of humoral immunity by eliciting neutralizing antibodies. Current insights encourage that a protective immune response to HCMV might benefit from the induction of virus-specific T cells. Whether addition of antiviral T cell responses enhances the protection by antibody-eliciting vaccines is however unclear. Here, we assessed this query in mouse CMV (MCMV) infection models by developing synthetic vaccines with humoral immunity potential, and deliberately adding antiviral CD8(+) T cells. To induce antibodies against MCMV, we developed a DNA vaccine encoding either full-length, membrane bound glycoprotein B (gB) or a secreted variant lacking the transmembrane and intracellular domain (secreted (s)gB). Intradermal immunization with an increasing dose schedule of sgB and booster immunization provided robust viral-specific IgG responses and viral control. Combined vaccination of the sgB DNA vaccine with synthetic long peptides (SLP)-vaccines encoding MHC class I-restricted CMV epitopes, which elicit exclusively CD8(+) T cell responses, significantly enhanced antiviral immunity. Thus, the combination of antibody and CD8(+) T cell-eliciting vaccines provides a collaborative improvement of humoral and cellular immunity enabling enhanced protection against CMV. Show less
Tondini, E.; Arakelian, T.; Oosterhuis, K.; Camps, M.; Duikeren, S. van; Han, W.D.; ... ; Ossendorp, F. 2019
High-risk Human Papilloma Virus (HPV) induced malignancies are an interesting target for immunotherapy as they invariably express the viral proteins E6 and E7 that allow specific recognition of... Show moreHigh-risk Human Papilloma Virus (HPV) induced malignancies are an interesting target for immunotherapy as they invariably express the viral proteins E6 and E7 that allow specific recognition of tumor cells without the risk of inducing autoimmunity. This thesis describes the preclinical development of pDNA vaccine candidates for the treatment of HPV16 induced malignancies. For this purpose gene-shuffled (SH) versions of HPV16 E6 and E7 were used to avoid the risk of transformation at the vaccination site. To improve the immunogenicity of E6SH and E7SH several optimizations strategies were evaluated. First it is shown that genetic fusion with Tetanus Toxin Fragment C (TTFC), results in a dramatic increase in immunogenicity. The resulting vaccine candidates TTFC-E6SH and TTFC-E7SH were also demonstrated to have lost their transforming potential. Secondly it is demonstrated that the mere addition of an endoplasmatic reticulum targeting sequence and a set of promiscuous CD4 helper epitopes results in an enormous increase of the immunogenicity of E6SH and E7SH. This design decreases the risk of raising competing carrier specific immune responses. Finally several nanoparticle based formulations of a model pDNA vaccine were evaluated and it is demonstrated that for in vivo applications it is essential to shield the cationic charge of such nanoparticles. Show less
Carstens, M.G.; Maaden, K. van der; Velden, D. van der; Ottenhoff, T.H.M.; Melief, C.J.; Ossendorp, F.; ... ; Jiskoot, W. 2011
This thesis introduces a novel T cell vaccination method that uses a tattoo machine to inject DNA in the skin of the vaccinee. In comparison to other experimental vaccination methods DNA tattooing... Show moreThis thesis introduces a novel T cell vaccination method that uses a tattoo machine to inject DNA in the skin of the vaccinee. In comparison to other experimental vaccination methods DNA tattooing is very strong: besides small laboratory animals also large animals mount strong T cell responses upon tattoo DNA vaccination. Show less
