Research Ingrid De Meester

Abstract

Chronic inflammation plays a significant role in both the onset and progression of many diseases, including, but not limited to, cardiovascular disease, chronic infections, cancer, and inflammatory organ diseases such as COPD, NAFLD, and IBD. Furthermore, acute infections may also trigger chronic inflammation and associated long lasting sequelae. As the prevalence of these diseases is increasing in Western societies and also emerging in other regions, research in this area can have a profound societal and scientific impact. Regulated cell death, barrier dysfunction, and immune modulation are key drivers of chronic inflammatory processes (Fig. 1). There is growing evidence for a limited number of common molecular pathways underpinning the regulation of these processes, and hence for a complex interplay in their pathophysiology. In this regard, Infla-Med brings together UAntwerp's leading basic and translational researchers in these three domains to form a bench-to-bedside and back consortium. The collaboration of complementary forces has enabled scientific breakthroughs in inflammation-focused research and has proven crucial in leveraging collaborations and funding in this competitive research field. For instance, Infla-Med's first 'stage' (2016-2019) resulted in more than € 23M in awarded funding with an overall stable 45% success rate since 2016. Moreover, halfway through Infla-Med's second 'stage' (2020-2022), we have already acquired the same amount of competitive grants. In terms of excellence, Infla-Med's principle investigators have achieved remarkable success in securing large, highly competitive grants for interdisciplinary research at local (BOF-GOA/IMPULS), national (FWO-EOS, iBOF), and international (ERA.Net, Innovative Medicines Initiative, coordination of H2020-MSCA-ITN and HE-MSCA-DN projects) levels. This shows that Infla-Med has established a very high-performing synergistic research framework among its principle investigators. The next 'stage' of Infla-Med will focus on discovering additional scientific breakthroughs and increasing our involvement in leading international research networks and acquiring international excellence funding (ERC). Four key strategic decisions support these ambitious aims for Infla-Med's next stage.

Researcher(s)

• Promoter: De Meyer Guido
• Co-promoter: Caljon Guy
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Benedicte
• Co-promoter: Francque Sven
• Co-promoter: Segers Vincent
• Co-promoter: Smet Annemieke
• Co-promoter: Vanden Berghe Tom
• Co-promoter: Van Der Veken Pieter
• Co-promoter: Wullaert Andy

Research team(s)

• Physiopharmacology (PHYSPHAR)

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a protease biomarker that is selectively expressed on activated fibroblasts. Strongly FAP+ fibroblasts are found in >90% of all tumors, in fibrotic tissue and in tissue remodelling. At UAntwerp, UAMC1110 was earlier discovered: a very potent and selective FAP inhibitor. Radiolabeled derivatives of UAMC1110, called FAPIs, can be used as diagnostics or as therapeutics ('theranostics'). Nowadays, a steeply increasing number of FAPIs is being synthesised. However, there are no good predictions for the in vivo behaviour of novel FAPIs and the understanding of the interactions between FAP and its inhibitors is still limited. Within this FWO-SB application, we will bridge the gap between the present in vitro biochemical evaluation and the in vivo preclinical experiments. In addition, we will provide an expansion of our knowledge about FAP-FAPI interactions. This increase in insights will be realised by: 1) FAPI-PLA, a highly interdisciplinary in vitro platform to accelerate the preclinical development of FAP-targeted theranostics. FAPI-PLA will enable a thorough evaluation of new FAPIs through a combination of biophysical characterization and assessment of their behaviour in a cellular context such that they may eventually be used as theranostics. 2) the elucidation of FAP-FAPI interactions by nanoscale structure determination to expand our knowledge on the interactions.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Elvas Filipe
• Co-promoter: Sterckx Yann
• Co-promoter: Van Der Veken Pieter
• Fellow: de Groot Anke

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Thymus specific serine protease (TSSP) is a serine protease first identified in the late nineties. It is highly expressed in the thymus and barely detectable in other organs. TSSP is the third member of the S28 group of serine proteases, along with prolyl carboxypeptidase (PRCP) and dipeptidyl peptidase II (DPPII). It is named a serine protease because of its predicted enzymatic activity due to the presence of three amino acids (serine, aspartate and histidine) at positions highly similar to the ones forming the catalytic site of PRCP. PRCP cleaves off C-terminal amino acids adjacent to a proline, while DPPII only cleaves short peptides after proline at the second position starting from the N-terminus, hence the name 'dipeptidyl'-peptidase. This difference in substrate specificity makes it hard to predict the cleavage specificity of the third member, TSSP. Why should TSSP be studied further? In the thymus, TSSP is highly expressed by the cortical epithelial cells (cTEC's) and at lower levels by thymic dendritic cells. Since the functional T-cell repertoire is shaped in the thymus by positive and negative selection through interactions with Major Histocompatibility Complex (MHC)-peptide complexes expressed by cTECs and bone marrow derived antigen-presenting cells, TSSP could possibly be involved in this process. Peptides for loading on MHC class II molecules are generated by sequential proteolysis of endosomal proteins. Furthermore, during T-cell maturation in the thymus, massive cell death occurs in the cortical region as thymocytes that recognize self-antigens have to be deleted. The molecular mechanisms underlying this 'thymocyte cleanup campaign' and the high expression of TSSP in this region remain outstanding questions in the field. On the long term, a better knowledge on the structure-function relationship of TSSP may contribute to a better insight in the T-cell selection processes in the thymus. It is hypothesized that a primary function of TSSP is to somehow limit central tolerance to increase the diversity of the functional CD4+ T cell repertoire. Clearly, further characterization of TSSP's enzymatic activity is an essential next step in the search for its function in the shaping of the immune repertoire. In this basic science project we want to start the biochemical study of this hitherto uncharacterized protein by 1) structure-guided recombinant production, purification and quality control of recombinant mouse TSSP (rmTSSP) and human TSSP (rhTSSP); 2) characterization of TSSP substrate specificity and comparison with DPPII and PRCP and 3) selection and development of antibodies and inhibitors as further tools to study TSSP biology. To increase the chance of obtaining valuable antibodies we will use two approaches: i) selection of camelid single domain antibodies (sdAbs) from a library and ii) generation of classical monoclonal antibodies (mAbs). As a first step in the development of potent and selective inhibitors, we will screen a protease inhibitor library of small molecules to select a lead compound that can be used as a starting point for follow-up research. It is astonishing that this thymus specific enzyme has not yet been studied in more detail. One reason may be that the recombinant production of well-folded active TSSP could not be achieved to date. The Laboratory of Medical Biochemistry (LMB) has a longstanding expertise in studying the other members of the serine protease family S28. Therefore, there is a momentum to build on recent AlphaFold 2-based structural knowledge and experimental expertise on related proteins to definitely unravel the catalytic activity of TSS.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Sterckx Yann
• Fellow: Van Meel Kim

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Radioligand therapy has recently received renewed attention as promising treatment option to improve cancer patient outcome. Compared to conventional cancer treatments, this strategy involves a more specific targeting of therapeutic radionuclides to the tumor, which aims to increase treatment efficacy. Despite recent progress, currently available treatments show insufficient tumor killing and normal tissue toxicity, and we hypothesize that a pretargeted click-to-release (C2R) strategy can bridge this gap. Within this strategy, we propose to explore Fibroblast Activation Protein (FAP) inhibitors as tumor targeting vectors, to deliver a therapeutic radionuclide fragment intracellularly using cell permeable, cleavable transcyclooctene (dcTCO) constructs and compare it with conventional dTCOs. To reinsure intracelular release, after C2R, we designed new structures containing an RGD peptide (with integrin αvβ3 binding specificity). Our molecular constructs also aim to prevent FAP efflux, by using a guanidinium and nicotinoyl residualizing groups. This project will evaluate the reactivity, in vitro stability, logD and radiochemical yield of the new molecules, and the C2R efficiency of the dcTCOs. A FAP inhibitor (dimer) will be weaponized with a tetrazine handle to be the targeting vector and biorthogonal pair of these new constructs, and it's affinity and selectivity will be evaluated in vitro, against other proteases. The dcTCOs and dTCOs with better reaction kinetics and C2R efficiency (dcTCOs) will be selected for the development of 18F- and 125I-radiolabeled probes. The celular uptake and internalization will be evaluated on tumor cells (FAP positive cells, integrin αvβ3 positive cells, both FAP and αvβ3 positive). This project is a innovative strategy to improve the radiation dose delivered to the tumor and improving treatment outcome, while reducing radiotoxicity and achieving better treatment tolerability.

Researcher(s)

• Promoter: Elvas Filipe
• Co-promoter: De Meester Ingrid
• Co-promoter: Van Der Veken Pieter
• Fellow: Da Silva Gustavo

Research team(s)

• Molecular Imaging and Radiology (MIRA)

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a protease biomarker that is selectively expressed on activated fibroblasts. Strongly FAP-positive fibroblasts are present in > 90% of all tumor types, in fibrotic disease lesions, and in other pathologies that involve tissue remodeling. Researchers at UAntwerpen earlier discovered UAMC1110: to date the most potent and selective FAP-inhibitor described. UAMC1110 is now used widely as the FAP-targeting vector of the so-called FAPIs: radiolabeled derivatives of UAMC1110. These FAPIs can be used as diagnostics or as therapeutics ('theranostics'), depending on the radiolabel. While these FAPIs have shown impressive clinical results in oncodiagnosis, radiotherapy applications are somewhat lagging. This is because the original FAPIs typically have short FAP-residence times, leading to short tissue retention and fast wash-out of radioactivity. To date, mainly optimization strategies that significantly discount on 'druglikeness' have been explored. Examples include the use of 'multi-valency' and the addition of lipophilic, albumin-binding moieties. Remarkably, only a very limited number of papers have focused on optimizing the UAMC1110 pharmacophore. Some of these again have led to very large molecules. Druglikeness is not a critical parameter for most oncology applications, because of the leaky tumor vasculature and loose tissue. In very dense tissue, such as in fibrosis, druglikeness can however be expected to become a key parameter. The host recently discovered several series of druglike, pharmacophore-optimized FAPIs, for which patent applications were submitted. For the last of these applications (submitted in August 2023), we would like to generate additional data that support and exemplify the claims. More specifically, we want to synthesize novel druglike FAPIs that are covered by the patent application's Markush Formula and associated biological data.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: Elvas Filipe

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Dipeptidyl-peptidase 9 (DPP9) is a post-proline cleaving serine protease. Lately, the enzyme captured the attention of immunology and oncology researchers, after it was shown that DPP9 inhibition causes pyroptosis (pro-inflammatory cell death), selectively in myeloid leukemia cells. To date, no selective DPP9 inhibitors have been reported. However, in early 2023 the host lab discovered a series of subnanomolar DPP9 inhibitors with selectivity indices > 103 against all other proline-selective proteases (unpublished data). These molecules will be structurally optimized and investigated toward three specific applications: 1) Inhibitors with maximal pyroptosis induction potency. Structural parameters will be investigated that maximally disrupt the protein-protein interaction (PPI) between DPP9 and the inflammasome sensors NLRP1 and CARD8. Disruption of these PPIs sets off pyroptosis induction. 2) Selective activity-based probes for DPP9. Proof-of-concept for these molecules will also be delivered by tracking active DPP9 inside live cells and quantifying it in cell lysate. 3) Inhibitors with optimized in vivo pharmacokinetics. This will maximize the impact and clinical translatability of our endeavors. Optimal molecules can become drug candidates, for example against myeloid leukemias.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Fellow: Peeters Sarah

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Dipeptidyl-peptidase 9 (DPP9) is a proline-selective serine protease. Recently, DPP9 inhibition has shown to cause pyroptosis selectively in acute myeloid leukemia cells. Pyroptosis is a lytic form of programmed cell death. The process typically recruits immune cells and inflammatory mediators, causing a localized activation of the innate immune system. This is appealing for leukemia treatment, because the immune-response to leukemic cells is typically subdued. Recent mechanistic insight shows that DPP9 suppresses pyroptosis through a stabilizing protein-protein interaction (PPI) with the NLRP1 and CARD8 inflammasome sensors. DPP9 inhibition mildly impairs the interaction, causing some NLRP1 and CARD8 release and induction of pyroptosis. We hypothesize that clearance of DPP9 from the cytoplasm could be a more effective way of causing pyroptosis than inhibition. To this end, PROTAC and AUTAC approaches will be pursued in this project. PROTACs and AUTACs are heterobifunctional molecules that mediate the degradation of a protein of interest (POI) by hijacking the cell's own proteasome and autophagic system, respectively. The project covers preparation and in depth biological investigation of the novel molecules. It can be expected to significantly advance the state-of-the art in the field of DPP9 research, targeted protein degradation and leukemia therapy.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: Martinet Wim
• Fellow: Nozal García Vanesa

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a cell surface marker of Cancer- Associated Fibroblasts (CAFs) in most sarcomas and in > 90% of carcinomas. Together with its negligible expression in most other tissues, this makes FAP a nearly-universal biomarker of tumors. During the past years, diagnostic and therapeutic targeting of FAP with so-called 'FAPIs' has attracted strong attention from nuclear medicine/oncology specialists. Noteworthy, all FAPIs owe their remarkable tumor homing potential to a potent and selective FAP-binding subunit: UAMC1110, reported by the applicants of this proposal. Because FAPIs require further optimization of tumor residence time, we aim to link multiple FAPIs or FAPI subunits to gold nanoparticles (AuNPs). In this way, we hope to obtain FAP-targeting AuNPs with unprecedented FAP affinity and tumor residence, due to the 'multivalency effect'. The nanoparticles will be investigated as cancer theranostics in a mouse model of colorectal cancer and as diagnostics in a lateral flow assay.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: Elvas Filipe
• Co-promoter: Sterckx Yann
• Co-promoter: Stroobants Sigrid

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Inflammation is an immune response in which the cytosolic multiprotein complexes, inflammasomes, are crucial signaling platforms. Only recently, a master inflammasome regulator has been uncovered: the widely distributed intracellular serine protease dipeptidyl peptidase 9 (DPP9). More specifically, DPP9 is a binding partner and a negative regulator of two related Pathogen Recognition Receptors (PRRs), named 'NLRP1' and 'CARD8'. Precise insight into the mechanism is lacking as no selective DPP9 inhibitors have been reported to date. Interestingly, our preliminary data indicate that there are some differences in DPP9 (co)localization/complex formation with these PRRs among different human blood cell types. UAntwerp developed promising DPP9 inhibitors (Benramdane S, submitted) and PROTACs (heterobifunctional molecules that target a protein to degradation), creating a momentum to characterize and validate them for use in a cellular context. This PhD's overarching goal is to apply the two best DPP9 inhibitors to visualize [DPP9-CARD8] and [DPP9-NLRP1] interactions in situ in primary human blood cells and, at the molecular level, to determine the binding parameters of these interactions, both in the absence and presence of the best DPP9 inhibitors. To check whether effects are 'on-target', control experiments using PROTACs and a DPP9-/- cell line will be included. Understanding DPP9-inflammasome-related protein interactions is required to evaluate their potential as drug-targets.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Sterckx Yann
• Co-promoter: Van Der Veken Pieter
• Fellow: Mertens Kathleen

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Europe has a high cancer burden: in 2020, 2.7 million EU citizens were diagnosed with the disease and 1.3 million lost their lives to it. This toll is expected to increase further, mainly because Europe's population is ageing: by 2035, cancer will be the leading cause of death in the EU. In 2021, the EC published its 'Europe's Beating Cancer Plan' (EBCP), calling for a big push in cancer research. Cancer diagnostics and therapeutics should rapidly become more effective and selective, patient-friendly and personalized. All these goals are directly addressed by developing better tumor targeting strategies. Typically, they consist of equipping diagnostics and therapeutics with a vector unit. The vector unit binds to a protein that is overexpressed on cancer cells or in the Tumor Micro-Environment (TME), causing the diagnostic or therapeutic payload to accumulate in the tumor. Over the last decades, huge effort has gone in approaches that use antibodies as vectors, but return-on-investment has overall been rather poor. Exciting, recent innovations rely on small molecule vectors that target TME proteases. Proteases are ideal candidates for tumor targeting: they are often strongly overexpressed in the TME and possess an active site that allows high-affinity anchoring of vectors. Members of this consortium have played a leading role in these developments. OncoProTools wants to force breakthroughs in cancer diagnosis and therapy by: 1) Exploring innovative venues for protease targeting in CAR T cell therapy. 2) Discovering novel vectorsthat bind to other TME proteases: cathepsins S, B, L and granzyme B 3) Personalize applications of protease targeting: deliver innovative diagnostics through deeper understanding of TME biology. At the same time, OncoProTools will deliver a training program that truly captures the MSCA values, to 10 Doctoral Candidates. They will be provided with all capabilities to become leaders of tomorrow's R&I in Europe

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: Elvas Filipe
• Fellow: Shikut Nikita
• Fellow: Thanopoulou Magdalini

Research team(s)

• Medicinal Chemistry (UAMC)

Project website

Project type(s)

• Research Project

Abstract

Dipeptidyl peptidase 9 (DPP9) is a cytosolic serine protease. It is related to, among others, the diabetes drug target DPP4 and to DPP8. Especially DPP8 is highly homologous with DPP9 and both enzymes generally occur simultaneously in the cells. Recent research shows that DPP9 is an NLRP1-inflammasome inhibitor and, most notably, that DPP9 inhibition leads to inflammatory cell death (pyroptosis) in most Acute Myeloid Leukemia (AML) cell lines. This effect is also reproduced in mouse models of AML, indicating that DPP9-inhibition could be an innovative strategy to treat AML and related hematological malignancies. To date, only non-selective DPP8/9-inhibitors have been reported and these compounds are known to have toxicity and stability issues, limiting their application to preclinical settings. Recent, preliminary data obtained by the hosting labs show that specific structural modifications of the marketed DPP4 inhibitor vildagliptin, yields molecules with unprecedented selectivity for DPP9 over all related proteases. These molecules will be further optimized in this project to obtain analogues with maximized DPP9 selectivity. All molecules will be evaluated for DPP9 potency/selectivity. Selected representatives will be further investigated in cells and for the most promising molecule, in vivo pharmacokinetics will be determined in healthy mice. Finally, the most promising inhibitor will also be used as a structural template for activity-based biomarker probes of DPP9.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Hans
• Fellow: Filippi Nicolò

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Preliminary evidence shows that the enzyme dipeptidyl peptidase 9 (DPP9), which is present in macrophages, plays a role in controlling the inflammatory response and associated cell death. Inflammation is a normal response of tissues against infections, chemical insults and physical injuries. However, in some cases, it becomes chronic and causes harm. A better understanding of the inflammatory process provides new therapeutic opportunities. In this project, we will focus on the role of the intracellular protease DPP9 in macrophages derived from human white blood cells. The crystal structure of DPP9 was recently solved, and can now be used to design DPP9 inhibitors. We will develop selective and potent DPP9 inhibitors and substrates. We will also engineer the human THP-1 cell line to eliminate DPP9. Using the DPP9 inhibitors and engineered cell lines, we will determine under which conditions DPP9 plays a key role in macrophage function. Finally, the molecular binding partners of DPP9 will be identified. We will look for natural substrates as well as non-substrate interaction partners of DPP9 in macrophages. The interactions will be characterized at the molecular level. Our fundamental biochemical findings and novel chemical tools will significantly advance the development of future therapies for diseases where DPP9 plays a role.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Van Der Veken Pieter

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

The Research Consortium of Excellence Infla-Med combines multidisciplinary expertise of eight research groups from two faculties to perform fundamental and translational research on inflammation, including: inflammatory gastrointestinal, cardiovascular, lung and kidney disorders, sepsis and allergies, as well as parasitic diseases, thereby focusing on specific inflammatory cell populations, including monocytes/macrophages, mast cells, basophils and lymphocytes. The approach of the Infla-Med consortium is twofold. Firstly, fundamental studies are performed to unravel the pathophysiological mechanisms underlying inflammatory conditions in order to enable more rational, targeted and effective intervention strategies. Secondly, Infla-Med aims to identify and validate novel therapeutic targets by screening chemical compounds in early drug discovery studies and by using an extensive platform of in vitro assays and in vivo models. The close collaboration with the Antwerp University Hospital (UZA) creates the opportunity to directly translate and clinically validate experimental findings. Thereby, Infla-Med contributes to two Frontline Research Domains of the University of Antwerp: 'Drug Discovery and Development' and 'Infectious Diseases'. Over the past four years, the multidisciplinary collaborations within Infla-Med have proven to be very successful and productive. By integrating the Infla-Med unique expertise on drug development, in vitro assays and clinically relevant animal models (validated with human samples), significant competitive funding has been acquired at European, national and UAntwerp levels with a success rate of more than 45%, which is far above the (inter)national average. Noteworthy, several Infla-Med projects have also made the transition towards valorization, demonstrating that Infla-Med results obtained from both fundamental research and well-designed preclinical studies can successfully be translated into clinical trials.

Researcher(s)

• Promoter: De Meyer Guido
• Co-promoter: Augustyns Koen
• Co-promoter: Caljon Guy
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Benedicte
• Co-promoter: Ebo Didier
• Co-promoter: Heidbuchel Hein
• Co-promoter: Vanden Berghe Tom

Research team(s)

• Physiopharmacology (PHYSPHAR)

Project website

Project type(s)

• Research Project

Abstract

This project represents a research contract awarded by the University of Antwerp. The supervisor provides the Antwerp University research mentioned in the title of the project under the conditions stipulated by the university.

Researcher(s)

• Promoter: De Meester Ingrid
• Promoter: Hendriks Dirk

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a protease biomarker that is selectively expressed on activated fibroblasts. Strongly FAP+ fibroblast are found in >90 of all tumors, in fibrotic tissue and in tissue remodeling. Researchers at UAntwerp earlier discovered UAMC1110: today the most potent and selective FAP inhibitor available. Radiolabeled derivatives of UAMC1110, called FAPIs, can be used as diagnostics or as therapeutics ('theranostics'). Nowadays, a steeply increasing number of FAPIs is being synthesized. This research proposal aims to bridge the current in vitro gap between FAPI design, synthesis and initial biochemical characterization on the one hand and the preclinical in vivo evaluation on the other. This will be realized by the development of FAPi-PLA, a test platform comprising: (1) a validated method for structure elucidation of FAP-FAPI complexes, (2) highly sensitive biosensor-based FAP-FAPI-binding assays for kinetic analyses of FAP-FAPI interactions and (3) a relevant cell-based assay to predict the FAPI-target residence time in a biological context. The project aims to obtain data for three existing FAPIs as reference compounds and at least two new FAPIs that are in the pipeline. To accelerate the development of FAPIs, there is an urgent need for such an efficient centralized platform. Within this project, we will develop the technology needed to create 'FAPi-PLA', a complete and modular in vitro FAPI test platform to accelerate FAPI development.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: de Groot Anke

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Various proteases play an important role in the tumor microenvironment (TME). Hence, tackling tumors by targeting these TME proteases is a very promising approach in the fight against cancer. FAPIs, highly potent and selective probes based on UAMC1110, an inhibitor developed at the UAntwerp, are currently evaluated in clinical studies. In contrast, the targeting of other highly relevant TME proteases is lagging behind. Granzyme B (GRZB) is the most abundant protease present in the granules of cytotoxic immune cells present in the TME and plays a role in the targeted tumor cell destruction. Despite decades of research, many aspects of GRZB immunobiology remain enigmatic. It is currently unknown which percentage of GRZB is active in the TME. To study whether imaging or measuring active GRZB levels has advantages over visualizing total GRZB, there is a need for selective and high affinity GRZB probes. Given the potential of GRZB in cancer diagnosis and treatment, this postdoc challenge aims to reinvigorate the quest for the generation of highly selective GRZB inhibitors starting from a literature-based lead compound. The postdoc will be challenged to determine the high-resolution structure of this inhibitor – GRZB complex to fuel rational ligand design. The labs participating in this call are involved in the recently funded OncoProTools (Protease-guided tumor targeting tools to revolutionize cancer diagnostics and treatment) HE-MSCA-Doctoral Network (granted upon first submission, UAntwerp as the lead applicant). UAntwerp will host two PhD students (PhD1 and PhD2) from January 2023 onwards. Since this international project will be the start of a new GRZB-research line within the 'Tumor Micro-environment Proteases' theme, support by a postdoc is highly desirable. The project will be supported by docking studies for in silico design of new inhibitors (UAMC, Hans De Winter). We will offer in-house access to granzyme activity assays, recombinant protein production and purification infrastructure, protein-ligand interaction assays and a lab fully equipped for structural biology (LMB, Y. Sterckx). The Postdoc candidate is expected to bring own experimental expertise with protein expression and structural biology into the GRZB theme and he/she will benefit from a dynamic international network of academic and industrial partners in the field of oncology.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: De Winter Hans
• Co-promoter: Elvas Filipe
• Co-promoter: Sterckx Yann
• Co-promoter: Van Der Veken Pieter
• Fellow: Pimenta Fernandes Andreia

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Dipeptidyl peptidase 9 (DPP9) is a cytosolic serine protease. The enzyme has lately attracted extensive international research attention, because of its recently discovered role in inflammatory cell death (pyroptosis). Among other things, it has been demonstrated that inhibition or knock-down of DPP9 leads to induction of pyroptosis in acute myeloid leukemia cells. Also in other oncology domains, DPP9 inhibition is currently investigated as a pyroptosis induction mechanism. In this form of programmed cell death, cancer cells are not only killed off, but they also release proteins that cause a strong, local upregulation of the innate immune system. This immunotherapeutic effect is generally seen as highly promising. To date, however, no clinically useful and selective DPP9 inhibitors have been reported. Very recently, however, the applicants discovered a series of low nanomolar small molecule DPP9 inhibitors with unprecedented selectivities toward all enzymes that are related to DPP9. Given the properties of these compounds and their significant valorisation potential, a patent application was submitted during June 2022. This IOF-POC project is expected to generate scientific data that should corroborate further the submitted patent application. In addition, these data should convince industrial partners to take a licence on the submitted patent. Next to new chemical data, this project application covers pharmacokinetic, pharmacodynamic and in vitro phenotypic research toward new inhibitors.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: Caljon Guy
• Co-promoter: De Meester Ingrid

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a serine protease expressed on stromal cells of > 90% of all epithelial cancers, whereas its expression is almost undetectable in normal tissues. In addition, FAP expression is highly restricted and transiently increased in adult tissues during wound healing, inflammation, or fibrosis in activated fibroblasts. The highly focal expression makes FAP a promising diagnostic marker and an attractive therapeutic target, not only in cancer, but also in fibrotic and cardiovascular diseases. UAntwerp has an approved patent for the only highly potent, selective and orally bioavailable small molecule inhibitors of FAP known to date (US9346814 and EP2804859). One of the compounds in this patent (UAMC1110) has received widespread attention as the structural basis for FAP-targeted positron emission tomography (PET) radiotracers and FAP-targeted radiopharmaceutical therapies, which are currently heavily investigated and in high demand by the pharmaceutical industry. Also, at UAntwerp, research is ongoing that aims at producing UAMC1110 derivatives, with main applications in the in vitro diagnostics field. In addition, in the scope of a former IOF-POC project the applicants of this proposal have collaborated on the discovery of 18F-labeled UAMC1110 derivatives that can be used as PET diagnostics in oncology, fibrosis and related domains, and in cardiovascular disease. Recently, we have developed a small library of 18F-labeled probes that show promising stability, pharmacokinetics and tumour-targeting properties in human glioblastoma cancer xenografts. Based on this preliminary data a patent application has been filed. However, there is still room for improvement by reducing the accumulation of these probes in non-targeted organs, which is especially relevant in the context of radionuclide therapy. Through structural optimization (increasing the polarity of the probes), this POC project aims to expand this library and deliver compounds having high metabolic stability and less or no accumulation in liver and gastrointestinal tract. Following the proof-of-concept, these optimized probes will be included in the patent that will be filed in early June 2022, which should strengthen the industrial development of these probes as PET-diagnostics and theranostics.

Researcher(s)

• Promoter: Elvas Filipe
• Co-promoter: De Meester Ingrid
• Co-promoter: Stroobants Sigrid
• Co-promoter: Van Der Veken Pieter

Research team(s)

• Molecular Imaging and Radiology (MIRA)

Project type(s)

• Research Project

Abstract

This proposal is situated in the field of drug discovery and has the overall objective of further validating and implementing a proof-of-concept high-throughput screening (HTS) assay we have developed in-house. The acronym EVZYM refers to our findings that extracellular vesicles (EVs) represent a novel source for native, active target enzymes against which small-molecule compounds can be screened for their potential to inhibit target enzyme activity. This poses a significant advantage in the quest for novel drug candidates as the availability of active enzyme preparations is essential for successful HTS assay outcome; i.e., large compound libraries are screened for their inhibitory potential and the identified "hits" form the starting point for further optimization. A first goal of the project encompasses upscaling EV isolation, and determining optimal storage conditions that guarantee EV stability such to maximally enhance their application in industrial settings. The second goal consists of further validating and implementing our in-house EVZYM-based HTS assay for a target protease which is naturally present and enriched in EVs. This target protease is TMPRSS2, a human serine-type protease present on the cell surface of which the activity enhances corona- and influenzavirus infections, thereby making it an attractive target for the development of anti-viral chemotherapeutics. Within this second objective, we also aim to obtain a recombinant version of TMPRSS2, which represents an added value because i) this represents an alternative source of target protease for HTS assay validation and ii) no documented highquality preparations of recombinant TMPRSS2 are currently available on the market.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Sterckx Yann

Research team(s)

• Medical Biochemistry

Project website

Project type(s)

• Research Project

Abstract

The coronavirus SARS-CoV-2, causative of COVID-19, currently causes an unprecedented pandemic. Human SARS-CoV-2 infections are enabled by two events that occur at the host-virus interface. First, viral attachment to host cells is mediated by an interaction between the SARS-CoV-2 'spike' protein and its host receptor angiotensin converting enzyme 2 (ACE2).Next, the virus is "primed" for host cell entry through proteolytic cleavage of SARS-CoV-2-spike protein by other surface-exposed host proteases such as TMPRSS2. Inhibition of TMPRSS2-enabled "priming" negatively impacts SARS-CoV-2 infectivity. Unfortunately, the currently available TMPRSS2 inhibitors (such as camostat) are nonspecific. For the development of inhibitors with an increased specificity and high potency, a better knowledge of the characteristics of the protease are urgently needed. This project aims to lay the indispensable foundation for the rational design of specific TMPRSS2 inhibitors in the battle against SARS-CoV-2 and COVID-19. This will be realized in two work packages (WPs) and 6 interrelated and measurable deliverables (D). The project will focus on following research questions: (1) What is the extended substrate specificity of TMPRSS2? and (2) What is the correlation between TMPRSS2 inhibition and neutralization of SARSCoV- 2 infectivity in vitro? The deliverables of the project include the availability of active recombinant human TMPRSS2, methods to quantify its activity, data on the extended substrate specificity and on the inhibitory potency of a set of 100 compounds from the library of protease inhibitors of the UAntwerp research group on Medicinal Chemistry (UAMC). The correlation of the inhibitory potency of these compounds with their effect on in vitro infectivity of SARS-CoV-2, together with data on extended TMPRSS2 substrate specificity, are an indispensable prerequisite for optimal planning of larger collaborative projects on host protease targeting as a therapeutic approach in the fight against COVID-19. Moreover, given the recently acquired expertise in structural biology in our lab, this project will lay a solid foundation for future structural studies of hit compounds in complex with TMPRSS2, which can in turn fuel rational drug design to generate more potent and specific compounds.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Bracke An
• Co-promoter: Sterckx Yann

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Fibroblast activation protein (FAP) is a serine type protease that is expressed on stromal cells of > 90% of all epithelial cancer types, and also in pathological lesions associated with other diseases characterized by tissue remodeling. It is virtually absent in healthy adult tissues. FAP is being studied both as a therapeutic target and a biomarker/diagnostics target: not only in oncology, but also in, e.g., different fibrosis types and cardiovascular disease. UAntwerp has an approved patent for the only highly potent, selective and orally bioavailable small molecule inhibitors of FAP known to date (US9346814 and EP2804859). One of the compounds in this patent (UAMC1110) receives widespread attention as a potential therapeutic and as the structural basis for diagnostic probes. Also at UAntwerp, research is ongoing that aims at producing UAMC1110 derivatives, with main applications in the diagnostics field. A VLAIO-funded O&O project was recently initiated with HistoGeneX, under which fluorescent and colorigenic UAMC1110 derivatives are used to characterize oncology biopsy samples. The applicants of this project now want to apply their expertise in the domain of FAP ligand design for the discovery of new, FAP-targeting PET probes that can be used in diagnostics.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: Elvas Filipe
• Co-promoter: Stroobants Sigrid

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

Despite the presence of a sound expertise, structural biology is currently not well-embedded within the University of Antwerp. Hence, UAntwerp researchers are dependent on collaborations with external partners to be productive and competitive in this field. Structural biology at UAntwerp will only successfully come of age by investing in the acquisition of basic infrastructure that will adequately support the existing expertise. In this project proposal, funding is requested for the purchase of the Mosquito Xtal3, a state-of-the-art crystallization robot that has become an indispensable workhorse in any structural biology laboratory. The Mosquito Xtal3 allows fast, robust and high-throughput crystallization of biological macromolecules, which is a basic requirement for structure determination through macromolecular X-ray crystallography.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Cappoen Davie
• Co-promoter: De Winter Hans
• Co-promoter: Sterckx Yann
• Co-promoter: Van Ostade Xaveer

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

There is compelling evidence that the enzyme dipeptidyl peptidase (DPP) 9 is involved in inflammation and cell death in macrophages. However, large gaps in our understanding of the exact underlying mechanisms remain. Research has mainly been limited to macrophage cell lines and murine primary macrophages. Therefore, our first objective is to study the effect of the DPP8/9 inhibitor 1G244, currently the most selective inhibitor available, on the production and secretion of cytokines and chemokines by human peripheral blood mononuclear cells, monocyte-derived macrophages, M1, M2 and M4 macrophages. The effect on cell viability will also be evaluated in these primary cells. Our second objective includes the identification of DPP9 interaction partners in the monocytic cell line THP-1 and human primary macrophages. Pull-down experiments using recombinant human DPP9 as a bait, followed by LC-MS/MS identification, as well as proximity ligation assays will be applied. We foresee to identify at least one additional interaction partner apart from the FIIND domain in NLRP1/CARD8. The third objective is to characterize the interaction between DPP9 and the bindings partner(s) identified in objective 2 at the molecular level, using isothermal titration calorimetry and grating-coupled interferometry. After the initial characterization of the interactions, we will use anti-DPP9 antibodies with known epitopes in order to identify the regions in DPP9 that are involved in the interaction.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Sterckx Yann
• Fellow: De Loose Joni

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Immunotherapy shows great potential in the treatment of cancer. Unfortunately, primary resistance is frequently occurring, hence the urgent need for biomarkers. Fibroblast activation protein (FAP), an enzyme that is selectively expressed in cancer-associated fibroblasts in 90% of all human epithelial tumors, may become a promising predictive biomarker for immunotherapy resistance. However, to date, there are no validated, specific tools to determine FAP expression and/or activity within the tumor microenvironment (TME). Therefore, the first goal of this project, is the development of specific tools and accurate methods to detect FAP within the TME. We will develop 2 fluorescent FAP-assays, one based on a fluorescently labelled inhibitor and the other on a fluorescently labelled anti-FAP antibody. The third assay is based on a FAP-specific substrate for histochemistry that allows in situ amplification of the signal. Secondly, early detection of metastasis remains a major hurdle in diagnosis and there is an urgent need to explore new biomarkers of early metastasis. Recently, it is suggested that circulating FAP +cCAFs within the blood of metastatic patients could be interesting for that purpose. Nonetheless, no specific, accurate tools and techniques are available for identification and enrichment of FAP +cCAFs. Consequently, the second goal of this project is to develop new tools and methods to identify and enrich FAP+cCAFs in the peripheral blood of metastatic cancer patients

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Van Der Veken Pieter
• Fellow: Van Rymenant Yentl

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Immunotherapy is revolutionizing the clinical management of multiple cancer types including DNA mismatch repair-deficient tumors (Galluzi et al., 2018). However, even in this preselected group of patients, good and complete response are achieved in only one fifth of the patients (Le et al., 2016; Le et al., 2017). Thus, there are still enormous opportunities for improvement. The presence of an immunosuppressive tumor environment may be key to further optimization of immunotherapy (Jiang et al., 2016). Extracellular matrix accumulation and rigidity, and neo-expression of matrix proteins may be involved in T cell exclusion from the proximity of cancer cells or impaired T cell functionality. Cancer-associated fibroblasts (CAF) create an imbalanced biomechanical force in the tumor by the deposition of extracellular matrix, and by their contractility and proteolytic activity. CAF are abundant in mismatch repair-deficient tumors and their presence is associated with poor disease outcome (Kalluri 2016). Clinical targeting of CAF has been challenging due to its heterogeneous nature. We propose to target CAF making use of commonly expressed fibroblast growth factor receptor (FGFR) and platelet-derived growth factor receptor (PDGFR) or protease activity by fibroblast-activation protein (FAP). The advantage of FGFR/PDGFR inhibitors and FAP inhibitors is their complementary targeting of CAF biology either growth/differentiation vs proteolysis. Thus, we will evaluate whether impeding immune cell infiltration/functionality by CAF could explain non-responsiveness to immune checkpoint inhibitors in patients with DNA mismatch repair-deficient tumors. To test this hypothesis we will make use of three work packages: Workpackage 1: Human DNA mismatch repair-deficient tumors will be analyzed for the spatial localization and organization of collagen fibers, CAF and T-cells and data will be correlated with clinicopathological parameters. Workpackage 2: Patient-derived CAF will be treated with FGFR/PDGFR inhibitors or FAP inhibitors and outcomes such as (neo)matrix deposition, collagen rearrangement, and contractility will be evaluated and the consequent functional impact on T-cell chemotaxis, proliferation and differentiation will be tested. Workpackage 3: Syngeneic mouse tumor models will be used to evaluate if CAF targeting may improve efficacy of immune checkpoint inhibitors (such as anti-PD-1). We anticipate that CAF targeting combined with immunotherapy will synergistically induce and sustain the anti-tumor immune response, resulting in durable tumor regression in a larger population. Encouraging data in the preclinical study will enable fast translation into a clinical phase I/II trial.

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

(This research project aims to acquire dedicated knowledge on the protein 'Fibroblast activation protein alpha', further called 'FAP', in the context of personalized immune therapy. We will investigate whether FAP can be a biomarker for resistance to immunotherapy in urothelial carcinomas. In addition, we explore the presence of FAP in urine (as a non-invasive biological biomatrix) to monitor or predict the response to therapy for urothelial carcinomas.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Van Der Veken Pieter

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Analysis of off-target effects of experimental compounds following the agreement between the Antwerp University and the university of Helsinki. Further details are confidential------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Physical and functional interactions between biomolecules play pivotal roles in all aspects of human health and disease. Gaining a greater understanding of these biomolecular interactions will further expand our understanding of diseases such as cancer, metabolic diseases and neurodegeneration. At UAntwerp, 7 research groups have joined forces to obtain the absolutely necessary equipment to measure these interactions with a Biomolecular Interactions Platform (BIP). This will allow to detect interactions and precisely determine binding affinities between any kind of molecule, from ions and small molecules to high-molecular weight and multi-protein complexes. The BIP will also allow to identify collateral off- targets, crucial in the drug discovery field. Access to a BIP will strongly support ongoing research projects and bring research within the BIP-consortium to a higher level. Since biomolecular interactions are highly influenced by the methodology, it is recommended to measure the interaction by several, independent techniques and continue with the most appropriate one. For this reason, the consortium aims at installing a BIP, consisting of several complementary instruments that each measure biomolecular interactions based on different physical principles. They wish to expand the existing Isothermal Titration Calorimetry with two complementary state-of-the- art techniques: MicroScale Thermophoresis and Grating- Coupled waveguide Interferometry.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Delputte Peter
• Co-promoter: De Wael Karolien
• Co-promoter: Dewilde Sylvia
• Co-promoter: De Winter Hans
• Co-promoter: Kooy Frank
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Maudsley Stuart
• Co-promoter: Van Der Veken Pieter
• Co-promoter: Van Ostade Xaveer

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

The requested infrastructure (comprehensive liquid chromatograph-ion mobility-quadrupole time of flight mass spectrometer LCxLC-IM-QTOFMS) combines several state-of-the-art technologies into one platform which aims at bringing metabolomics research to the next level. As such, the infrastructure will deliver a combined five-dimension separation and detection technology, the first of its kind in Belgium. This instrument will be dedicated to metabolomics research, the science of endogenous metabolites in cells, tissues or organisms. The infrastructure will be able to optimally separate, detect and identify the very broad and complex chemical space of metabolites ranging from very polar (e.g. amino acids) to non-polar (e.g. lipids and hormones) at low nanomolar concentration range. Within UA, there is a growing need to combine the currently scattered efforts in metabolomics, an Emerging Frontline Research Domain in the UA research scene. Research ranges from drug discovery (mode of action and pharmacokinetic profiling), biomarker and toxicity studies to advanced data-analysis and systems biology approaches, but a dedicated metabolomics infrastructure to strengthen these studies is currently missing. As such, the investment in a core facility together with the gathering of nine research groups from five departments and two faculties would centralize the metabolomics research. This will position UA as a key player in the academic metabolomics research in the BeNeLux and worldwide.

Researcher(s)

• Promoter: Covaci Adrian
• Co-promoter: Augustyns Koen
• Co-promoter: Baggerman Geert
• Co-promoter: Bervoets Lieven
• Co-promoter: De Meester Ingrid
• Co-promoter: De Meyer Guido
• Co-promoter: Hermans Nina
• Co-promoter: Laukens Kris
• Co-promoter: Lemière Filip
• Co-promoter: Maes Louis
• Co-promoter: van Nuijs Alexander

Research team(s)

• Toxicological Centre

Project type(s)

• Research Project

Abstract

Inadequate perfusion, oxygen limitation and cell metabolic changes, are key factors contributing to the formation of an acidic microenvironment in tumors.1 Two pivotal adaptations of tumor cells, related to maintaining intracellular pH and homeostasis in an acidic environment, have recently received significant attention: (1) the presence of chronic autophagy and (2) the overexpression of carbonic anhydrases (CAs), mainly CA IX and CA XII. Aiming to counter these essential tumor survival processes, the proposal deals with discovering and thoroughly evaluating novel autophagy inhibitors and and dual [autophagy-CA] inhibitors. The following three Work Packages will be elaborated during the course of the project: 1) Biopharmaceutical optimization of the host's Atg4B-inhibitor set. 2) Design and synthesis of dual [Atg4B-CA] inhibitors. 3) Biological characterization of Atg4B- and hybrid [Atg4B-CA] inhibitors in acidic cancer cell cultures and in an animal model of colorectal cancer.

Researcher(s)

• Promoter: Van Der Veken Pieter
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Hans
• Co-promoter: Lambeir Anne-Marie
• Fellow: Vrijdag Johannes

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

IBS affects around 18% of the general population. It is one of the most common disorders seen by physicians. However, the IBS market is commercially weak due to the limited understanding of its pathophysiology and the availability of limited treatment options. In fact, IBS is largely seen as a syndrome rather than a disease. By increasing the understanding of the underlying mechanisms of IBS coupled to validation of therapeutic and diagnostic targets, we have the ambition to turn IBS "from a syndrome into a disease". To achieve this, we want to establish an academic knowledge platform and an industrial network in Flanders that is able to tackle the major challenges in the IBS field, to identify and validate novel therapeutic and diagnostic targets and to develop them into novel therapeutic and diagnostic solutions. When available, this network will put Flanders at the forefront of innovation in the emerging IBS field.

Researcher(s)

• Promoter: Augustyns Koen
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Benedicte
• Co-promoter: Lambeir Anne-Marie

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

The complex mechanism involved in the pathogenesis of these metabolic disorders remains poorly understood. Recent findings indicate that the enzyme prolyl carboxypeptidase (PRCP) plays a role in body weight control and glucose homeostasis by inactivating melanocyt-stimulating hormone MSH, a neuropeptide which causes a loss of appetite. We aim to investigate whether 'peripheral' (outside the central nervous system) actions of PRCP also contribute to this function. Our preliminary experiments have identified apelin, which also regulates feeding behaviour and glucose metabolism, as a novel PRCP substrate. Firstly, we will characterize this cleavage in vitro and investigate whether truncation by PRCP alters the function of apelin and other peptide substrates. Secondly, the role of PRCP on in vivo cleavage of peripheral apelin will be investigated. The effect of pharmacological inhibition of PRCP will be studied with emphasis on apelin activity.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: De Hert Emilie

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

The complex mechanism involved in the pathogenesis of these metabolic disorders remains poorly understood. Recent findings indicate that the enzyme prolyl carboxypeptidase (PRCP) plays a role in body weight control and glucose homeostasis by inactivating melanocyt-stimulating hormone MSH, a neuropeptide which causes a loss of appetite. We aim to investigate whether 'peripheral' (outside the central nervous system) actions of PRCP also contribute to this function. Our preliminary experiments have identified apelin, which also regulates feeding behaviour and glucose metabolism, as a novel PRCP substrate. Firstly, we will characterize this cleavage in vitro and investigate whether truncation by PRCP alters the function of apelin and other peptide substrates. Secondly, the role of PRCP on in vivo cleavage of peripheral apelin will be investigated.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Fellow: De Hert Emilie

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project represents a formal research agreement between UA and on the other hand the client. UA provides the client research results mentioned in the title of the project under the conditions as stipulated in this contract.

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project represents a research contract awarded by the University of Antwerp. The supervisor provides the Antwerp University research mentioned in the title of the project under the conditions stipulated by the university.

Researcher(s)

• Promoter: Augustyns Koen
• Co-promoter: Apers Sandra
• Co-promoter: Cos Paul
• Co-promoter: Delputte Peter
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Hans
• Co-promoter: D'Haese Patrick
• Co-promoter: Hermans Nina
• Co-promoter: Kiekens Filip
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Maes Louis
• Co-promoter: Pieters Luc
• Co-promoter: Van Der Veken Pieter
• Fellow: Joossens Jurgen
• Fellow: Pauwels Maxim
• Fellow: Verhoeven Kristien

Research team(s)

• Medicinal Chemistry (UAMC)

Project type(s)

• Research Project

Abstract

The Infla-Med consortium performs fundamental research on the pathophysiological processes of inflammatory diseases (cardiovascular, gastrointestinal, renal and infectious disease) by using a multidisciplinary approach (pathophysiology, pharmacology, biochemistry and medicinal chemistry). The consortium is embedded within the research priorities 'Drug Research' and 'Infectious Diseases' of the University of Antwerp. Recently, the University of Antwerp assigned the Infla-Med consortium as Research Consortium of Excellence.

Researcher(s)

• Promoter: De Meyer Guido
• Co-promoter: Augustyns Koen
• Co-promoter: De Meester Ingrid
• Co-promoter: De Winter Benedicte
• Co-promoter: D'Haese Patrick
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Maes Louis
• Co-promoter: Vrints Christiaan

Research team(s)

• Physiopharmacology (PHYSPHAR)

Project type(s)

• Research Project

Abstract

Acute lung injury remains the third major cause of mortality worldwide, and it is assumed that excessive inflammatory responses could be involved. The precise role of dipeptidyl peptidases (DPPs; a family of enzymes that cleave off dipeptides from the amino terminus of peptides) in the pathophysiology of acute lung injury is poorly understood. Taken broadly, the DPP family consists of DPPIV, fibroblast activation protein alpha (FAP), prolyl oligopeptidase (PREP), DPP8 and DPP9. DPPIV inhibitors are used in the treatment of diabetes type 2, but evidence for other roles of DPPIV is also emerging. Despite a presumed role of individual peptidases in lung disease, knowledge on DPPs in acute lung injury remains limited. Previously, we have shown that DPPIV inhibitors protect against lung ischemia-reperfusion induced injury. Apart from that, we discovered that DPP9 has a role in macrophage activation, which is an important component of acute lung injury. The current project aims to explore the hypothesis that DPPIV, DPP9 and related peptidases play a role in the pathophysiology of acute lung injury. We will study the expression of DPPs in both an infectious and a non-infectious mouse model of acute lung injury. Subsequently, we will determine the effect of DPPIV inhibition on the outcome, and will assess whether DPPs have a role in lung macrophages. We will compare the animal findings with measurements in human tissue to study the translational potential of our results.

Researcher(s)

• Promoter: Adriaensen Dirk
• Co-promoter: De Meester Ingrid
• Co-promoter: Kumar-Singh Samir
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Van Schil Paul

Research team(s)

• Laboratory of cell biology and histology

Project type(s)

• Research Project

Abstract

In a first part of the project we will investigate the protein expression and enzymatic activity of PRCP in the circulation. Thereafter, we will perform in vitro experiments to study the cleavage of apelin and enterostatin by PRCP and compare cleavage efficiency with other known PRCP substrates. A third objective is to investigate apelin and enterostatin cleavage by PRCP in vivo and to find out whether PRCP influences their effect on body weight and metabolism. Understanding how peptide hormones are degraded by PRCP may open new approaches for therapeutic intervention.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Fellow: Kehoe Kaat

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project fits in the study of the role and expression of DPP9 in lung pathophysiology with an emphasis on lung fibrosis. However, DPP9 is part of a larger family of DPPs with structural similarities and overlapping substrate specificities. Initially, we want to establish a DPP atlas of the lung to provide context to the study of DPP9 specifically. Our second and main objective is to form a picture of DPP9's role and expression in the lung, starting from our current knowledge of DPP9 in human macrophages, towards a broader take on DPP9 and lung fibrosis.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Fellow: Vliegen Gwendolyn

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Ocular Surface diseases (OSD) such as dry eye syndrome (DES) show an estimated prevalence between 15 and 29%. The only FDA approved and on subscription dry-eye treatment is cyclosporine 0.05% (Restasis®), but this formulation is not available in the EU. Novel therapies for OSD are therefore needed. The expertise within ADDN fosters a unique opportunity to set up a preclinical platform on OSD leading to an increased collaboration with industrial partners.

Researcher(s)

• Promoter: Cos Paul
• Co-promoter: Augustyns Koen
• Co-promoter: De Meester Ingrid
• Co-promoter: Joossens Jurgen
• Co-promoter: Kiekens Filip
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Maes Louis
• Co-promoter: Van Der Veken Pieter

Research team(s)

• Laboratory for Microbiology, Parasitology and Hygiene (LMPH)

Project type(s)

• Research Project

Abstract

The effect of vaccination during pregnancy on bioactive components in breast milk (antibodies against pertussis and influenza, the total amount of SIgA and its subclasses and lactoferrin) will be examined. In addition, we will study the influence of storage conditions on the bioactive components. The differences between breast milk from mothers of preterm and term infants will be investigated in cooperation with the department of Neonatology at UZA.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Van Damme Pierre
• Fellow: De Schutter Sara

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

In a first part of the project we will investigate the protein expression and enzymatic activity of PRCP in the circulation. Thereafter, we will perform in vitro experiments to study the cleavage of apelin and enterostatin by PRCP and compare cleavage efficiency with other known PRCP substrates. A third objective is to investigate apelin and enterostatin cleavage by PRCP in vivo and to find out whether PRCP influences their effect on body weight and metabolism. Understanding how peptide hormones are degraded by PRCP may open new approaches for therapeutic intervention.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Fellow: Kehoe Kaat

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project will focus on the role of dipeptidyl-peptidase 9 (DPP9) in leukocytes. This enzyme is capable of cutting a dipeptide off a peptide after a proline at the penultimate position. However, its physiological role remains elusive. We want to solve the answer to this problem by tackling three key questions. Where exactly do we find DPP9 in leukocytes? It is important to know where in the cell DPP9 resides and if it moves upon cellular activation. Also, do we find equal amounts of DPP9 in different types of leukocytes? Can we identify interaction partners of this large intracellular protein? To determine the function of DPP9, it helps to know with which proteins it interacts. If the function of those proteins is known, it is likely that DPP9 has a function in the same pathway. Can we change cellular functions by changing the expression and/or enzyme activity of DPP9? We can inhibit DPP9 function by either inhibiting its formation or its enzymatic activity. Both methods might lead to (different) effects on the cellular level and indicate in which cellular roles DPP9 is involved. With these three approaches the physiological role of DPP9 in leukocytes might finally be revealed.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Waumans Yannick

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project aims to unravel the effects of DPP4 inhibition on collagen and collagen-derived dipeptide metabolism. We will develop and validate methods to quantify, in biological matrices, dipeptides resulting from DPP4 mediated cleavage. Next, the effects of DPP4 inhibition on the collagen metabolism and the dipeptide profile will be studied in vitro in fibroblast and osteoblast cultures. The in vivo relevance of our findings will be evaluated by studying the effects of long-term DPP4 inhibition in vivo in a rat model of type 2 diabetes. The focus will be on cardiac and renal collagen metabolism and dipeptide levels in plasma, urine and tissues.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Behets Geert
• Co-promoter: Covaci Adrian

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project will focus on the role of dipeptidyl-peptidase 9 (DPP9) in leukocytes. This enzyme is capable of cutting a dipeptide off a peptide after a proline at the penultimate position. However, its physiological role remains elusive. We want to solve the answer to this problem by tackling three key questions. Where exactly do we find DPP9 in leukocytes? It is important to know where in the cell DPP9 resides and if it moves upon cellular activation. Also, do we find equal amounts of DPP9 in different types of leukocytes? Can we identify interaction partners of this large intracellular protein? To determine the function of DPP9, it helps to know with which proteins it interacts. If the function of those proteins is known, it is likely that DPP9 has a function in the same pathway. Can we change cellular functions by changing the expression and/or enzyme activity of DPP9? We can inhibit DPP9 function by either inhibiting its formation or its enzymatic activity. Both methods might lead to (different) effects on the cellular level and indicate in which cellular roles DPP9 is involved. With these three approaches the physiological role of DPP9 in leukocytes might finally be revealed.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Waumans Yannick

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Dipeptidyl peptidases are enzymes that cleave N-terminal dipeptides from peptides with proline at the penultimate position. Dipeptidyl peptidase IV is by far the most extensively studied member of this family of serine proteases. Recently, Zhai et al [1] described a decrease in ischemia/reperfusion injury after lung transplantation by flushing and storage of the graft in a solution with the irriversible DPPIV inhibitor, AB192. [2] The goal of this doctoral thesis is to investigate this positive effect on cellular level by measuring the expression of dipeptidyl peptidases (activity-, protein- and mRNA-level) in primarily islolated lung microvascular endothelial cells and the effect of reduced oxygen tension on the expression levels. Secondly, other possible targets of AB192 are investigated and the therapeutically available DPPIV inhibitors (vildagliptin and sitagliptin) are tested for the same positive effects during ischemia-reperfusion injury.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Matheeussen Veerle

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project aims to better understand the effects of chronic dipeptidyl peptidase (DPP) inhibition on pre-defined aspects of cardiovascular, renal and bone (patho)physiology. Inhibitors with defined selectivity profiles will be developed as tools. Expression and inhibition of DPP4 and related peptidases will be studied on the molecular level, in cultured cells and in rat models of ischemia/reperfusion injury of heart and kidney.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Augustyns Koen
• Co-promoter: De Keulenaer Gilles
• Co-promoter: D'Haese Patrick
• Co-promoter: Lambeir Anne-Marie

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

this research project studies proline selective peptidases. It has the following aims : 1. Characterization of inhibitors and selection of potent and specific inhibitors of DPP4 related enzymes DPP8, DPP9 and FAP. 2. Study of the expression of the DPPP mambers in endothelia of different origin and this under normoxia as well as hypoxia. 3. In vitro study of the effect of selective ans not selective inhibition on endothelial cell activation. 4. The in vitro study of the effect of selective and non-selective DPP inhibition on collagen metabolism of fibroblasts.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Scharpe Simon

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Dipeptidyl peptidases are enzymes that cleave N-terminal dipeptides from peptides with proline at the penultimate position. Dipeptidyl peptidase IV is by far the most extensively studied member of this family of serine proteases. Recently, Zhai et al [1] described a decrease in ischemia/reperfusion injury after lung transplantation by flushing and storage of the graft in a solution with the irriversible DPPIV inhibitor, AB192. [2] The goal of this doctoral thesis is to investigate this positive effect on cellular level by measuring the expression of dipeptidyl peptidases (activity-, protein- and mRNA-level) in primarily islolated lung microvascular endothelial cells and the effect of reduced oxygen tension on the expression levels. Secondly, other possible targets of AB192 are investigated and the therapeutically available DPPIV inhibitors (vildagliptin and sitagliptin) are tested for the same positive effects during ischemia-reperfusion injury.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Matheeussen Veerle

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This project concerns the molecular and biochemical study of new human dipeptidyl peptidases (DPPs). The project aims to (1) determine which dipeptidyl peptidases are present in human leucocytes besides DPPIV, (2) identify and characterize these peptidases physicochemically, (3) study which substrates are cleaved by these peptidases and (4) test known inhibitors of dipeptidyl peptidases for selectivity.

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

This research plan aims to answer the following specific questions concerning FAP, DPPII, DP8 and DP9. The experimental objectives can be grouped around 3 themes: chromogenic and fluorogenic substrates, peptide substrates and inhibitors. The experimental results will be interpreted with the aid of available structural information (crystal structure of DPIV is published recently; DP8 and 9 show primary sequence homology, DPPII does not) in order to obtain a better insight in substrate binding and catalysis by the members of this family of serine type peptidases.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie
• Co-promoter: Scharpe Simon

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Maes Marie-Berthe

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

During the study of CD26/DPPIV in human leucocytes, it appeared that some of the X-Pro-releasing activity wasn't inhibited by DPPIV specific inhibitors. Preliminary experiments showed that at least some of the X-Pro-releasing activity was due to several other dipeptidylpeptidases. Primarily human dipeptidyl peptidase II (DPPII) will be purified, followed by a biochemical and enzymological characterization (synthetical substrates and natural occuring peptides). Human leucocyte cellines and periferal blood mononuclear cells will be screened on the presence of DPPII. Following biological evaluation of new DPPII inhibitors (collaboration with the laboratory of farmaceutical chemistry, Prof. A. Haemers and Prof. K. Augustyns), the function of DPPII in human leucocytes will be studied.

Researcher(s)

• Promoter: De Meester Ingrid
• Fellow: Maes Marie-Berthe

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

The AVANTI J-20XP refrigerated centrifuge is a high performance centrifuge that accomodates a number of rotors allowing forces to 82,000 x g. The swinging bucket rotor accomodates 1 liter bottles and microplates. New technology allows fast accel and decel times and shorter overall run times. Optionally the centrifuge may be equiped with a elutriator rotor or JCF-Z continuous flow zonal rotor, making it a multifunctional basic instrument for long term use. The SPECTRAmaxPLUS384 is a spectrophotometer with a built in cuvette port and microplate drawer. Standard spectrophotometer and microplate reader applications can be run on the same instrument (from 1 sample to 384 samples at a time). It has a full spectral range (190-1000nm) using a monochromator tunable 1.0 nm increments. The narrow bandwidth provides exceptional accuracy and linearity. Essentially all UV/VIS spectrophotometric assays can be read in the apparatus (colorimetric assays, immunoassays, enzyme kinetics, kinetic turbidimetric methods).

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

The project deals with the search for physiological substrates of dipeptidyl peptidase IV (=CD26), a very specific aminopeptidase that is found in the bloodstream and on differentiated epithelial cells. It aims (I) to investigate which peptides are hydrolysed ; (2) to characterize the cleavage kinetically and (3) to study the biological consequences ofthe hydrolysis. Focus will be put on peptides ofthe chemokine and glucagon superfamily.

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: Scharpe Simon
• Co-promoter: De Meester Ingrid

Research team(s)

• Medical Biochemistry

Project type(s)

• Research Project

Abstract

Researcher(s)

• Promoter: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

This project concerns the study of the enzyme dipeptidyl peptidase IV, also identified as the activation antigen CD26. The study tries to get a more profound knowledge on the structure and function of this complex protein with proline-specific exopeptidase activity that is expressed on activated lymfocytes and certain endothelial and epithelial cells. At the moment we concentrate on the identification of natural substrates. Candidate-substrates include chemokines, neuropeptides and growth factors.

Researcher(s)

• Promoter: De Meester Ingrid
• Co-promoter: Scharpe Simon

Research team(s)

Project type(s)

• Research Project

Abstract

Evidence for the involvement of CD26 in T cell activation and proliferation is provided by several approaches using mAb and CD26 transfection in human leukemic T cell lines. Application of CD26 mAb recognizing the 5/9 epitope to deplete bone marrow for allegeneic bone marrow transplantation in leukemia results in low graft versus hart disease.

Researcher(s)

• Promoter: Scharpe Simon
• Co-promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie

Research team(s)

Project type(s)

• Research Project

Abstract

In this study we explore the structure and function of the lymphocytic activation antigen CD26, identified as dipeptidyl peptidase IV, a proline specific serine protease. The involvement of CD26 in T lymphocyte activation in investigated using specific inhibitors and monoclonal antibodies. To obtain structural information, we will start the expression of the proteasedomain of this molecule.

Researcher(s)

• Promoter: Scharpe Simon
• Fellow: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

Evidence for the involvement of CD26 in T cell activation and proliferation is provided by several approaches using mAb and CD26 transfection in human leukemic T cell lines. Application of CD26 mAb recognizing the 5/9 epitope to deplete bone marrow for allegeneic bone marrow transplantation in leukemia results in low graft versus hart disease.

Researcher(s)

• Promoter: Scharpe Simon
• Co-promoter: De Meester Ingrid
• Co-promoter: Lambeir Anne-Marie

Research team(s)

Project type(s)

• Research Project

Abstract

Behavioural observations in chronic pain and depression in animalmodels point to canmon elements in the pathophysiology. One could deduce that common neurochemical mechanisms are responsible. An animal model for chronic neuropathic pain allows to study the mediators in the inflanmatory response as well as endocrinological changes and adaptation in serotonine levels in the CNS. Analogy with data reported in the litterature concerning changes due to depression in animals, will be discussed.

Researcher(s)

• Promoter: Adriaensen Hugo
• Co-promoter: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

In this study we explore the structure and function of the lymphocytic activation antigen CD26, identified as dipeptidyl peptidase IV, a proline specific serine protease. The involvement of CD26 in T lymphocyte activation in investigated using specific inhibitors and monoclonal antibodies. To obtain structural information, we will start the expression of the proteasedomain of this molecule.

Researcher(s)

• Promoter: Scharpe Simon
• Fellow: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

In this study we explore the structure and function of the lymphocytic activation antigen CD26, identified as dipeptidyl peptidase IV, a proline specific serine protease. The involvement of CD26 in T lymphocyte activation in investigated using specific inhibitors and monoclonal antibodies. To obtain structural information, we will start the expression of the proteasedomain of this molecule.

Researcher(s)

• Promoter: Scharpe Simon
• Fellow: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project

Abstract

Dipeptidyl peptidase IV is purified from human lymphocytes; biochemical characteristics (like molecular mass, isoelectric point and glycorilation) are investigated together with its enzymatic properties.

Researcher(s)

• Promoter: Scharpe Simon
• Fellow: De Meester Ingrid

Research team(s)

Project type(s)

• Research Project