Viral hemorrhagic fever (VHF) is a group of acute diseases caused by highly infectious viruses including Ebola, Lassa, Dengue viruses. Its high mortality rate poses high risk to public health,... Show moreViral hemorrhagic fever (VHF) is a group of acute diseases caused by highly infectious viruses including Ebola, Lassa, Dengue viruses. Its high mortality rate poses high risk to public health, however, studies on VHF have been hampered due to the non-availability of proper models and incomplete knowledge on its mechanism. In order to fill this gap, this thesis presented new bioanalytical, lab-on-chip and single-cell assays to investigate changes in vascular biology and macrophage immunometabolism induced by VHF viruses. Firstly, an organ chip was developed to mimic the hemorrhagic shock syndrome caused by VHF viruses in vitro and test experimental drug candidates. In addition, acoustic force spectroscopy was applied to investigate the effect of Dengue on the cellular viscoelastic properties of endothelial cells at single-cell level. Then, metabolic profiling of endothelial cells and macrophages upon Ebola viral protein exposure was performed on bulk-level. Finally, the immunometabolism of human macrophages upon polarization was investigated by live single-cell metabolomics, setting the stage for future host-pathogen studies at single-cell level. Overall, this thesis will facilitate the understanding of VHF viruses and the development of treatment strategies. More importantly, the technologies developed here expectedly open up opportunities to combat the viruses that threaten global society. Show less
Ebola virus can trigger a release of pro-inflammatory cytokines with subsequent vascular leakage and impairment of clotting finally leading to multiorgan failure and shock after entering and... Show moreEbola virus can trigger a release of pro-inflammatory cytokines with subsequent vascular leakage and impairment of clotting finally leading to multiorgan failure and shock after entering and infecting patients. Ebola virus is known to directly target endothelial cells and macrophages, even without infecting them, through direct interactions with viral proteins. These interactions affect cellular mechanics and immune processes, which are tightly linked to other key cellular functions such as metabolism. However, research regarding metabolic activity of these cells upon viral exposure remains limited, hampering our understanding of its pathophysiology and progression. Therefore, in the present study, an untargeted cellular metabolomic approach was performed to investigate the metabolic alterations of primary human endothelial cells and M1 and M2 macrophages upon exposure to Ebola virus-like particles (VLP). The results show that Ebola VLP led to metabolic changes among endothelial, M1, and M2 cells. Differential metabolite abundance and perturbed signaling pathway analysis further identified specific metabolic features, mainly in fatty acid-, steroid-, and amino acid-related metabolism pathways for all the three cell types, in a host cell specific manner. Taken together, this work characterized for the first time the metabolic alternations of endothelial cells and two primary human macrophage subtypes after Ebola VLP exposure, and identified the potential metabolites and pathways differentially affected, highlighting the important role of those host cells in disease development and progression. Show less
Cardiovascular disease (CVD) is a major cause of death worldwide. The underlying cause of most CVD is atherosclerosis. Atherosclerosis is characterized by progressive plaque build-up in the... Show moreCardiovascular disease (CVD) is a major cause of death worldwide. The underlying cause of most CVD is atherosclerosis. Atherosclerosis is characterized by progressive plaque build-up in the arterial wall.Noncoding RNAs (ncRNAs) are RNAs that are not translated into protein. This thesis focuses on two types: microRNAs and small nucleolar RNAs (snoRNAs). MicroRNAs inhibit the production of proteins and act on multiple proteins simultaneously. In CVD, many different proteins are involved. Changing expression of one microRNA can therefore have a major impact.Numerous snoRNAs have been associated with diseases, including CVD. The function of half of the human C/D box snoRNAs, however, is unknown.The first aim of this thesis is to investigate inhibition of microRNA-494-3p in advanced atherosclerosis. The second aim is to elucidate the function of SNORD113-6, a snoRNA that is involved in CVD.The thesis shows that inhibition of microRNA-494-3p halts plaque progression and increases stability of advanced plaques. This reduces the risk of e.g. a myocardial infarction.Furthermore, SNORD113-6 influences the function of fibroblasts, scar cells, and thus plays a role in maintaining function of our blood vessels.These insights may open up new therapeutic possibilities in future treatment of CVD. Show less
