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.

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…

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

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.

Promotor: Prof.dr. J. Kuiper

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…

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

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

Wiskunde en Natuurwetenschappen

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.

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.

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

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…

The emergence of complex diseases resulting from abnormal cell-cell signaling and the spread of infectious diseases caused by pathogens are significant threats to humanity. Unraveling the dynamic mechanisms underlying cell-cell signaling and infectious disease spreading is crucial for effective disease…

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.

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.

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.

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.

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

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

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…

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

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.

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.

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…

Linnartz

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

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…

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…

This thesis is largely an experimental study on the formation of solid-state simple and complex organic molecules in the H2O-rich and CO-rich ice phases of dense interstellar clouds and dark cores.

Multiple stars, that is two or more stars composing a gravitationally bound system, are common in the universe.

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…

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…

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.

With the rise of multi-drug resistant bacterial pathogens, the possibility of a post-antibiotic world is quickly becoming reality.

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

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.

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

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: G.A. van der Marel, Co-promotor: J.D.C. Codée

Advanced mass spectrometry of glycosphingolipids takes the central stage in this thesis. Investigations focus on characterization of glycosphingolipid metabolism in health and disease with emphasis to the detection and accurate quantitation of known and so far unknown glycosphingolipids and closely…

To address the fundamental questions of how life on Earth emerged and how common life may be in the Universe, it is crucial to know the chemical composition of the planet-forming material.

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