Welcome to the website of the Laboratory of Cell Biology and Histology, interfaculty research group of the Faculty of Pharmaceutical, Biomedical and Veterinary Sciences and the Faculty of Medicine and Health Sciences.
Our core activities are concentrated on gaining a better understanding of the cell biology of human physiology and disease using high-end microscopy technologies. Check out our research topics.
Our Master Thesis Subjects
Serum amyloids along the gut-brain axis in Alzheimer’s disease
Tutor: Peter Verstraelen - Promoter: Winnok De Vos
Recent insights have challenged the traditional view of the brain being an immune-privileged organ, inert to peripheral immune activation. Epidemiological and preclinical studies have shown that the risk of developing Alzheimer’s Disease (AD), and hallmarks of neurodegeneration, can be exacerbated by inflammation in the gut. In this context, we have recently discovered that bacterial amyloids, produced by the enteric microbiome, are potent immune inducers in the gastro-intestinal tract and its enteric nervous system. Herein, serum amyloid A3 (SAA3) emerged as an important regulator that fuels a pro-inflammatory feed-forward response, typified by cytokine secretion and T-cell infiltration. Given their amyloidogenic properties, their long-range, blood-brain barrier-penetrant signaling potential, and elevated levels in AD patient brain, we hypothesize that serum amyloids represent important mediators of pathogenic gut-brain communication in AD. To test this hypothesis, we will make use of an APPnl-g-f/MAPT mouse model and study the effect of SAA overexpression and knockout on neuroinflammation and amyloid deposition. Using state-of-the-art microscopy and cellular models of the enteric and central nervous system, we will unravel the immune mechanisms that contribute to neurodegeneration in gut and brain.
Key words: Neurodegeneration, Enteric nervous system, Gut-brain axis, Inflammation, Microscopy
Studying the novel Mrgprb2/X2-mediated signaling pathway as driver of aberrant mast cell functioning in the colon and its resulting effects on visceral hypersensitivity associated with irritable bowel syndrome.
Tutor: Lana Lambeets – Promoter: Jean-Pierre Timmermans
Mast cells are immune cells that are typically associated with allergic reactions at mucosal surfaces. Here, mast cells form operating units with sensory nerves and can contribute to sensations of itch and pain. In the context of Irritable Bowel Syndrome (IBS), a frequently occurring gastrointestinal disorder characterized by abnormal pain signaling (i.e. visceral hypersensitivity), the involvement of abnormal mast cell functioning has been recognized, but the exact receptors and signaling mechanisms driving this aberrant mast cell functioning remain poorly understood. In this respect, the presence of a novel IgE-independent, ‘pseudo-allergic’ pathway of mast cell activation pathway in the colon, consisting of mouse Mrgprb2 and its human counterpart MRGPRX2, was recently discovered our lab. In this project, we will focus on the specific role of this novel Mrgprb2/X2-mediated signaling pathway as a driver of aberrant mast cell functioning in the pathophysiology of IBS and associated visceral hypersensitivity. In this way, this project might generate a novel paradigm in our understanding of IBS pathophysiology and may form a solid foundation for further studies into the therapeutic potential of this pathway in these conditions.
Keywords: Mast cell, Substance - Mrgprb2/X2 signalling, IBS, in vitro culture, translatome analysis, confocal imaging, VMR recordings, iPSC derived sensory neurons
Single cell-based staging of glioblastoma-infiltration in cerebral organoids
Tutor: Sarah De Beuckeleer – Promoter: Winnok De Vos, Tim Van De Looverbosch
With the advent of human induced pluripotent stem cell (iPSC) technology, it has now become possible to generate organoids that more faithfully capture part of the heterogeneity and three-dimensional context of the human brain. However, the complexity and optical inaccessibility of such tissue mimics hamper their adoption in a routine screening setting. We are developing an approach for in-depth cellular phenotyping of organoids, using multiplex staining, automated light sheet microscopy and deep learning. In this thesis we intend to apply this approach for staging the infiltration of glioblastoma (GBM) cells into cerebral organoids. To this end, we will seed iPSC-derived cerebral organoids with fluorescently labeled GBM cells with different invasive properties onto different types of organoids, ranging from immature to immune-competent. We will track GBM mobility and network formation as a function of time and characterize their cell cycle state, activation status and local context by means of post-hoc immunostaining to better understand the interplay of the GBM cells and the local microenvironment. Finally, we will evaluate the potential of candidate pharmacological agents to selectively interfere with GBM cell infiltration.
Key words: glioblastoma, organoids, morphological phenotyping, image analysis, light-sheet microscopy, deep learning
Tau-induced senescence in human mini-brains
Tutor: Johanna Van Den Daele – Promoter: Winnok De Vos, Johanna Van Den Daele
Defects in the microtubule associated protein tau typify a range of neurodegenerative disorders termed tauopathies, which includes Alzheimer’s disease. Recent studies point to the potential involvement of cellular senescence, an irreversible non-proliferative state, associated with inflammatory cytokine secretion, in disease development. However, the causality, timing, and afflicted cell types remain poorly characterized. The goal of this thesis is to define the exact causal relationship between senescence and tauopathy development in a human context. To achieve this, immune-competent cerebral organoids (containing neurons, astrocytes, and microglia) will be produced from human iPSC and pathology will be triggered by viral transduction and/or seeding of aggregation-prone tau variants. In-depth molecular characterization and microscopy-based spatial proteomics will help defining whether senescence is a driving factor in human tau pathology development.
Key words: Tauopathy, Cell biology, iPSC, senescence, Microscopy
Nuclear envelope stress in the development of glioblastoma multiforme
Tutor: Sarah Peeters - Promoter: Winnok De Vos
Glioblastoma multiforme (GBM) is one of the most lethal tumors, due to its high heterogeneity, extensive infiltration, and cell state plasticity. Recurrence is almost universal, and there is no cure, thus urging for novel research angles. GBM cells experience significant confinement owing to the high cell density and limited migration space in the brain, which alters their nuclear mechanics and might sensitize them to nuclear envelope (NE) stress. This process promotes DNA damage, which may contribute to genome instability, tumour invasion and aggressiveness. With this project, we will investigate the contribution of NE stress to the development of GBM. To this end, we will characterize the composition and fragility of the NE in a panel of patient derived GBM cells of varying aggressiveness (using qPCR, westerns and microscopy) and study the short-term and long-term effects of NE stress in a physiologically relevant 3D context (organotypic slices and organoids).
Key words: Glioblastoma, Cell biology, Nuclear envelope, DNA damage, Live cell imaging
Super-resolved analysis of clustered DNA damage repair in glioblastoma multiforme
Tutor: Mirthe Vandenputte - Promoter: Winnok De Vos
Glioblastoma multiforme is one of the most lethal cancers worldwide. Despite intensive multimodal therapy, including fractionated irradiation, recurrence is almost universal due to persistence of glioma stem-like cells (GSC) with strong intrinsic or acquired radioresistance. More targeted and efficient high-LET radiation regimens are under investigation, but limited insight into the complex DNA damage and repair hamper routine implementation. A better understanding of the behavior of GSC post-irradiation, demands an accurate quantification of repair pathways and their interactions, ideally at the level of the individual lesion. That is why we will develop an expansion microscopy to quantify the recruitment and dissolution of repair factors at DNA damage sites with close-to-nano-scale resolution. The established technique will be applied to a panel of patient-derived GSC with varying characteristics exposed to low- and high-LET radiation. We will directly relate the individual response to radiation to the cellular phenotype, tumor qualification and transcriptional data. Altogether, we intend to improve our mechanistic understanding into the molecular rewiring of gliomas causing treatment resistance and recurrence.
Key words: DNA damage, Radiation, Cancer, Expansion microscopy
Pathogen-immune interactions in Pseudomonas aeruginosa and Staphylococcus aureus pneumonia
Tutor: An Hotterbeekx – Promoter: Samir Kumar-Singh
Ventilator associated pneumonia (VAP) caused by Pseudomonas aeruginosa (PA) and Staphylococcus aureus (SA) is a major contributor to high mortality and morbidity in the intensive care unit. In an immune-humanized mouse model we previously showed that both pathogens interact differently in the presence of a human or mouse immune system. Here the student will further investigate the pathogen-immune interactions in in vitro cell-culture based assays. To do so, the student will perform bacterial cultures, measure bacterial interspecies competition and host cell responses, perform RNA extraction and quantitative PCR and will investigate structural changes using microscopy.
Key words: Pneumonia, Pseudomonas aeruginosa, virulence factors, biofilm, antibiotic resistance
Hyperthermia as a potential therapy in pancreatic ductal adenocarcinoma treatment
Tutor: Robin Colenbier - Promoters: John-Paul Bogers and Jean-Pierre Timmermans
Pancreatic ductal adenocarcinoma (PDAC) is the cancer type with the worst prognosis and very high resistance to conventional chemotherapeutic drugs. As a result, patients are in need of novel and efficacious treatments. Initial in vitro and in vivo experiments on the effect of moderate hyperthermia (up to 41.5 °C) have demonstrated synergism between hyperthermal treatment and some routinely used chemotherapeutic drugs for PDAC. Nevertheless, most in vitro evaluations have been performed on 2D monocultures. These models do not closely resemble the complex tumour environment, limiting the translational value of these results into clinical practise. During this project, the student will exploit our recently optimised chorio-allantoic membrane xenograft model to investigate several combinations of whole-body hyperthermia treatment (WBHT) with chemotherapeutic drugs in this chicken embryo-based in vivo/in ovo model. The aim is to discover a safe treatment protocol with improved anti-tumour efficacy, potentially allowing dose-reduction of the chemotherapeutic drugs. Aside from routine cell culture techniques, the student will be offered an active role in the planning and execution of the in ovo experiments, including (immuno-)histological analysis of the xenografted tumours and chick organs of interest. As the CAM model is relatively little used in the investigation of solid tumours, further optimisation and novel techniques are also being investigated.
Key words: pancreatic cancer, therapy resistance, whole-body hyperthermia, chorio-allantoic membrane model, tumour histology
