The aim of this thesis is to study cell-cell interactions and the development of an assay to explore and quantify the exchange of membrane compounds.

This work describes the use of click-to-release chemistry to get spatiotemporal control over immunocytokine activity. Until now, immunocytokines (cytokines coupled to a tumor-targeting-moiety) remained active throughout the body, being able to bind their respective receptors, causing mild to severe…

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.

Despite being the object of intense study, embryonic development has been difficult to model due to a number of reasons. First, complex tissues can be comprised of many cell types, of which we probably only know a subset.

In this thesis, we describe the potential of cell mechanical phenotyping for immune cell characterization, diagnosis, drug testing, as well as treatment of disease.

A new type of tripodal squaramide-based supramolecular hydrogels is developed and studied.

Mechanical interactions between cells and their environment play an important role in many biological processes.

Promotor: Prof.dr. J. Kuiper

This thesis describes the synthesis, analysis of various tetrazine bearing compounds and use in bioorthogonal chemistry.

In deze opleiding, verzorgd door het Leiden Institute of Chemistry, zoek je naar oplossingen voor complexe, maatschappelijke problemen in volksgezondheid en milieuvraagstukken. We bieden op maat gemaakte, individuele studieprogramma’s, en je hebt de mogelijkheid om onderzoek te doen in het buitenland…

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.

The aim of this thesis was to study phage infection in Streptomyces, focused on cell wall-deficient cells. Bacteriophages (or phages in short) attach to the cell wall of bacteria after which they replicate and lyse the host cell.

Cell-based medicinal products (CBMPs), such as CAR T cells, are highly complex biopharmaceutical products offering various treatment options for serious illnesses such as cancer or autoimmune diseases.

Cardiovascular disease is a major global burden and atherosclerosis is the main underlying pathological process.

Promotor: Prof.dr.ir. J.G.E.M. Fraaije, Co-promotor: A. Kros

Epithelial-mesenchymal plasticity (EMP) and tumor cell migration play an important role in cancer progression, and an improved understanding of the mechanisms underlying these concepts is essential for developing new targeted approaches.

There is a need for alternative methods to replace, reduce and refine (3R) animal experimentation. Combining experimental data from high-throughput in vitro studies with in silico modeling is a promising approach to unravel the effect of chemicals on living cells and to gain a better understanding of…

This thesis advances our understanding of lipid uptake, a vital first step in lipid metabolism, by developing innovative click chemistry-based tools to study how immune cells internalize lipids.

Synthetic hydrogels that mimic the natural extracellular matrix in the biophysical and biochemical cues it provides to cells are in high demand, however the cell phenotypes as they are observed in vivo in numerous cases have yet to be attained.

During embryonic growth, cells proliferate, differentiate, and collectively migrate to form different tissues at the right position and time in the body.

Almost all bacteria are enveloped by a cell wall that provides cellular protection.

If mankind wants to survive into the 22nd century, we will need to change the way we live drastically. The human impact on our planet is everywhere, we are changing the atmosphere, the oceans and the land, leading to global warming, climate change, loss of biodiversity and pervasive pollution. There…

In a typical glycosylation reaction, a donor is activated to form a (variety of) electrophilic species which can react with a nucleophilic acceptor, following a reaction mechanism having both SN1 and SN2 character.

Aspergillus niger is an important industrial producer of organic acids and enzymes producing large amounts of spent fungal biomass.

This dissertation aims to advance understanding of amoeboid single cell migration under the influence of changing physicochemical environmental properties. The particular focus is on the relatively unknown influence of differing physical properties in the extracellular environment, such as the migratory…

Acute cardiovascular syndromes, including myocardial infarction or stroke, are the principal cause of death in the Western society. The main underlying pathology of cardiovascular diseases is atherosclerosis, which is caused by the accumulation of lipids and inflammatory cells in the vessel wall, in…

Traditional drug discovery approaches have been hampered by (in vitro) cell-culture models that poorly represent the situation in the human body.

In this research project, we aimed to obtain more insight in the role of mast cells in the immune driven disorders rheumatoid arthritis and atherosclerosis.

In this thesis, we have studied cell images from two types of cells, including pollen grains and the immune cells, neutrophils. These images are captured using a bright field microscope and a confocal microscope.

This thesis focuses on two processes involved in fighting infections: metabolism and immune cell motility and navigation.

There is an urgent need for more physiologically relevant cell culture methods to guide compound selection in pre-clinical stages of the drug development pipeline.

This thesis systematically studies the physicochemical properties of non-planar, propeller-shaped, polycyclic aromatic hydrocarbons. The synthesis of several so-called propellerenes is described on a gram scale, using optimized procedures aimed at using less hazardous reagents and reducing the amount…

Light-Harvesting Complex II (LHCII) is responsible for light absorption and excitation energy transfer in plants and photosynthetic algae, while in high light it undergoes conformational changes by which it quenches excitations to prevent photodamage.

The bacterial cell wall is a nearly universal structure that offers protection and gives the cell its shape. However, environmental stressors, such as cell wall-targeting antibiotics and hyperosmotic conditions, can induce bacteria to shift to a wall-deficient state. It is unknown whether the lack of…

Plant-microbe interaction resulted in different physio/chemical responses by host plant and interacting rhizobacteria.

CONCLUSION: This study demonstrates that human macrophages can be induced to exert direct anti-tumor activity against osteosarcoma cells. Our observation that the induction of macrophage anti-tumor activity by L-MTP-PE required IFN-gamma may be of relevance for the optimization of L-MTP-PE therapy in…

Biopolymer sequencing with graphene edge-based tunnel junctions has the potential to overcome current limitations with the third generation of sequencing based on biological nanopores.

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…

In order to gain a better insight into the basis of the rapid jasmonic acid (JA)-mediated stress response, an integrated approach using a targeted high-resolution mass spectrometry-based (HRMS) platform, was conducted to monitor the metabolism of JA using the model system of cell suspension cultures…

Bacteria have the ability to alter their morphology in order to adapt to changing environments.

In this thesis the combinatorial use of bioorthogonal labelling and Electron Microscopy (EM)-based imaging techniques is explored to enable observations of specific molecular targets in their ultrastructural context within the cell.

Promotores: Prof.dr. G.F.A. Kersten, W. Jiskoot, Co-promotor: J-P. Amorij

Streptomyces are multicellular, Gram-positive bacteria in the phylum of actinobacteria which produce a high amount of bioactive natural products of which the expression is tightly coordinated with the life cycle.

Laboratory, observation and modeling work on the dissociation of polycyclic aromatic hydrocarbons in interstellar environments and the formation of new molecular species through the fragmentation process.

Promotor: C.A.J. Knibbe, Co-promotor: J.J. Boelens, R.G.M. Bredius

Cytotoxic T-cells (CTLs) are involved in the clearance of viruses and killing of tumor cells.

Promotor: Prof.dr. R. Verpoorte, Co-Promotores: N.R. Mustafa, A.E. Schulte

In het schoolvak scheikunde is de concept-context benadering ingevoerd. Hans Vogelzang onderzocht of de Scrum-methodologie kan helpen bij het vormgeven van lessen met deze benadering.

This dissertation contains four works during my PhD. Different biomaterials have been designed based on coiled-coil peptides. These biomaterials have a range of applications, inclusing drug delivery, cell sorting to cell-cell fusion.