The aim of this thesis is to explore the use of Bioorthogonal Antigens to study the cross-presentation pathway.

The research described in this thesis focused on the use of bioorthogonal antigens to investigate immunological processes in antigen presenting cells. Bioorthogonal antigens are antigenic proteins produced through recombinant expression in a methionine auxotrophic E. coli strain.

In order to be able to develop effective medicine and treatments to prevent or cure autoimmune diseases or cancer we need to understand the mechanisms how they arise and what drives their course.Unravelling the fundamental molecular mechanisms influencing the onset and course of diseases such as allergies,…

This thesis describes the development of a variety of mannosylated conjugates. Antigen presenting cells bear mannoside recognizing receptors that actively transport antigen into the cell. This thesis exploits this feature for the development of improved vaccines.

MHC class I and MHC class II molecules present peptides to the immune system to drive proper T cell responses. Pharmacological modulation of T-cell responses can offer treatment options for a range of immune-related diseases.

The first steps are made in personalised cancer vaccination strategies, which aim to induce a more specific immune response with fewer side effects. The activation of cytotoxic T cells is crucial for an effective immune response.

Nanoparticles can be used as delivery systems for both small molecules and macromolecules such as proteins, peptides or oligonucleotides. This thesis focuses on the use of liposomes, nanometric vesicles formed by a lipid bilayer enclosing an aqueous core. Liposomes are highly versatile delivery syst…

The intradermal administration route is attractive for vaccine delivery, because of the highly populated antigen-presenting cells in the skin. However, the skin’s main physical barrier, the stratum corneum, prevents vaccines from entering the skin.

This thesis describes the design, synthesis, and immunological evaluation of varying (neo)antigenic peptide conjugates containing either a TLR2 or a TLR7 agonist.

Cationic peptide amphiphile nanoparticles are employed for co-delivery of immune modulator CpG and antigen. This results in better targeting to the antigen presenting cells and eliciting strong Th1 response, which is effective against the intracellular pathogens.

Atherosclerosis is the main underlying pathology of cardiovascular disease. Atherosclerosis is caused by an immune response which is directed against (modified) lipoproteins which accumulate in the vessel wall.

For effective cancer immunotherapy by vaccination, co-delivery of tumour antigens and adjuvants to dendritic cells and subsequent activation of antigen-specific cytotoxic T cells (CTLs) is crucial. In this study, a synthetic long peptide (SLP) harbouring the model CTL epitope SIINFEKL was encapsulated…

Mycobacterium tuberculosis (Mtb), the pathogen causing tuberculosis (TB), is the leader among all pathogens responsible for the most human deaths today and it is considered as one of the top 10 causes of death worldwide. There is an increasing occurrence of multidrug-resistant and even totally drug-resistant…

Tuberculosis (TB) is a major global health problem caused by the bacterium Mycobacterium tuberculosis (Mtb). In 2015, there were estimated to be 10.4 million new cases and 1.8 million deaths ascribed to TB, making it one of the top 10 causes of death worldwide. Unfortunately, the only current registered…

Antibiotic resistance, caused by widespread use of antibiotics, leads to bacterial infections that are difficult, if not impossible, to treat and is a major worldwide health concern.

Promotores: W. Jiskoot, F. Ossendorp

The current hepatitis B vaccines need to be stored and transported under refrigerated conditions (2-8 degrees C). This dependence on a cold-chain is highly challenging in areas where hepatitis B virus infections are endemic.

Poly(lactic-co-glycolic acid) (PLGA) particles have been extensively studied as biodegradable delivery system to improve the potency and safety of protein-based vaccines. In this study we analyzed how the size of PLGA particles, and hence their ability to be engulfed by dendritic cells (DC), affects…

The objective is to develop in vitro antigen degradation assays in order to mimic the fate of the antigen in vivo.

In summary, the collective results described in this thesis show that nanoparticulate vaccines can be delivered intradermally by coated and hollow microneedles and evoke antigen-specific immune responses.

Transcutaneous vaccination is attractive because it is non- or minimally invasive, pain free and the site of administration (skin) is easily accessible. What’s more, transcutaneous immunization can lead to a strong immune response owing to the presence of immune-competent cells in the skin.

This thesis describes the design and synthesis of fragments of various cell wall carbohydrates of the Streptococcus species, including the branched Group B-specific antigen (GBC) of Group B Streptococcus, glycerol phosphate (GroP) modified group A carbohydrate (GAC), and the O-acetylated type 1 capsular…

The aim of this work was to study the applicability of antigen-coated pH-sensitive microneedle arrays for effective vaccination strategies. Therefore, a model antigen (ovalbumin) was coated onto pH-sensitive (pyridine-modified) microneedle arrays to test pH-triggered antigen release by applying the…

Promotoren: G.F.A. Kersten, W. Jiskoot, Co-promotor: J-P. Amorij

One of the main challenges in the development of an effective anti-cancer vaccine is the generation of an adequate and directed cellular immune response.

Vaccines are an extraordinary category of biopharmaceuticals. They are usually prophylactic and come in many types, from whole bacteria to peptides and nucleic acids. They are very cost effective and almost every human on the planet is vaccinated. The latter mandates that vaccines have to be extremely…

Vaccination via the skin or the mucosae

Traditionally, vaccines are administered intramuscularly using conventional hypodermic needles, which cause pain and distress. Microneedles are very short needles (smaller than 1 mm) that are practically invisible to the naked eye.

The current resurgence of whooping cough is alarming, and improved pertussis vaccines are thought to offer a solution. Outer membrane vesicle vaccines (omvPV) are potential vaccine candidates, but omvPV-induced humoral responses have not yet been characterized in detail.

Lipid nanoparticles (LNPs) have enabled the success of mRNA vaccines but remain limited in broader therapeutic use by challenges in delivery efficiency, targeting, and mechanistic understanding.

The Skin Barrier and Vaccination group is led by Prof. Joke Bouwstra. One of the key functions of the skin is its barrier function, which is located in the uppermost layer of the skin, the stratum corneum. The stratum corneum consists of enucleated dead cells (corneocytes) embedded in a lipid matrix.…

This thesis has described novel synthetic methods to produce a variety of (glyco)peptides and their application in the study of various immunological processes.

Promotor: Prof.dr. W. Jiskoot, Co-promotor: A. Kros

Influenza CD8(+) T-cell epitopes are conserved amongst influenza strains and can be recognized by influenza-specific cytotoxic T-cells (CTLs), which can rapidly clear infected cells. An influenza peptide vaccine that elicits these CTLs would therefore be an alternative to current influenza vaccines,…

Because of their large surface area and immunological competence, mucosal tissues are attractive administration and target sites for vaccination.

Despite the fact that gold nanoparticles (GNPs) are one of the most studied nanoparticles, there is still a necessity for new approaches allowing for effective protective coating to enable wider use of GNPs in biomedical applications.

Promotores: Wim Jiskoot; Ferry Ossendorp

This thesis focuses on using liposomes in two different treatment strategies; vaccination (or immunotherapy) and delivery of a small molecule, and in two different disease models; cancer and atherosclerosis.

Seasonal influenza vaccines provide protection against matching influenza A virus (IAV) strains mainly through the induction of neutralizing serum IgG antibodies. However, these antibodies fail to confer a protective effect against mismatched IAV. This lack of efficacy against heterologous influenza…

Atherosclerosis is a chronic inflammatory disease affecting millions of people world-wide.

This thesis investigates innovative and classical strategies in glycoconjugate vaccine development to address the growing threat of multidrug-resistant bacterial infections.

Atherosclerosis is the most prominent underlying pathology of cardiovascular disease and an important cause of major adverse cardiovascular events.

Tuberculosis is a major global health problem caused by the Mycobacterium tuberculosis complex, claiming more than a million lives annually.

Promotores: Prof.dr. J. A. Bouwstra, Prof.dr. W. Jiskoot

In the near future oral polio vaccine (OPV) will be replaced by inactivated polio vaccine (IPV) as part of the eradication program of polio. For that reason, there is a need for substantial amount of safe and more affordable IPV for low-income countries. Bioneedles, which are biodegradable mini-implants,…

Dissolving microneedles are a subgroup of microneedle types that completely dissolve within the skin. During this dissolving process the vaccine, stored in the needle matrix, is released into the skin.

The Immune Activation and Tolerance group is headed by Dr. Bram Slütter. Vaccination is an experimental, but promising, treatment strategy for atherosclerosis. Previous work has shown that immunization of mice with modified LDL particles can reduce atherosclerotic lesion development, however such vaccines…

In this book liposomes are explored as delivery system for allergen-specific immunotherapy. Both cationic and anionic formulations are prepared with Bet v 1, one of the allergens in birch pollen.