Research Eva Lion

Abstract

Next Generation Sequencing (NGS) has emerged as a suitable tool to evaluate and characterize the T Cell Receptor (TCR) immune repertoire. This approach paves the way for the use of the TCR repertoire study as a novel complex biomarker to track the exposure of individuals to non-self antigens and to develop new therapeutic strategies by improving our comprehension of the adaptive immune response against infectious agents and cancer antigens. The collaboration between Italy's Istituto Romagnolo per lo Studio dei Tumori "Dino Amadori" (IRST) and Belgium's University of Antwerp involves both these fields and aims to identify and characterize specific human TCRs via NGS to develop therapeutic TCR-T cells, exploiting experimental protocols, in silico analysis, and in vitro assays for T cell stimulation with antigens' pools. The first objective is to study the T cell response to mRNA-based COVID vaccines in healthy subjects and lymphoma patients from Emilia Romagna region through RNA samples sequencing and subsequent analysis of TCR specificity against SARS-CoV-2 proteins. The correlation between TCR diversity and strength with the amount of neutralizing antibodies will also be examined in consideration of the predicted HLA context, leading to an actionable SARS-Cov2 bulk TCR-seq database. Genomic instability, which is a common feature in cancer cells, often leads to the generation of chromosomal rearrangements and aneuploidy. Many are the examples today of gene fusions that promote cell transformation in different oncological settings. Those events lead to the unique opportunity to generate neoantigens that could be presented to the immune system in an HLA-restricted manner. Therefore, the second objective is the identification and validation of neoantigens originated from genetic fusion events in cancer patients already available in IRST. Subsequently, experiments will be focused on the identification of antigen-specific T cells and TCRs against neoantigens originating from selected genetic fusion events. To these ends, computational protein reconstruction and prioritization from the already available fusion genes database will be performed to retrieve fusion transcripts in hematological tumors. These peptides will be later synthesized and pooled to stimulate T cells, with subsequent expansion and characterization of the expressed receptors. Before that, a proof-of-concept T cell expansion and following TCR-identification experiments with model protein(s) for a known neoantigen will be set up.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Campillo Davó Diana
• Co-promoter: Meysman Pieter

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Recently, interest has grown in using self-amplifying RNA (saRNA) in vaccines for infectious diseases and cancer. SaRNA is a type of messenger RNA (mRNA) that contains the non-structural proteins of an alphavirus replicase complex that amplifies the original strand of RNA and allows the expression of proteins of interest in the host cell without risk of infection. Compared to conventional mRNA, saRNA-mediated expression of proteins of interest may last for 28 days, while lacks the risks of genomic integration or cell transformation of integrative technologies such as viral vectors, transposons, and CRISPR-based knock-in. Moreover, saRNA vaccines under clinical investigation show that saRNA is safe and elicits robust immune responses. However, this technology has not been explored yet to genetically engineer effector immune cells, such as T cells, ex vivo. Therefore, the START project aims to investigate and optimize saRNA transfection as an innovative and potent technology for genetically engineering T cells with chimeric antigen receptors (CARs) and T-cell receptors (TCR) against different hematological and solid cancer antigens, with a thorough evaluation of antitumor activity, T cell fitness and potential transcriptomic and cell metabolic changes that could be related to saRNA replication activity. The START project will provide the basis for the future generation of non-integrative and long-lasting CAR-T and TCR-T cell therapies for hematological and solid malignancies.

Researcher(s)

• Promoter: Lion Eva
• Fellow: Campillo Davó Diana

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

The emergence of immunotherapy has improved cancer treatment in many different ways. One of the specific approaches is T-cell receptor (TCR)-T-cell therapy, in which potent TCRs are introduced into patient T cells in the laboratory, after which they can specifically destroy unwanted cells in the body. Although this therapy shows promising results, identification of potent TCRs remains a major hurdle. Due to the immense diversity of TCR repertoires, it is challenging to efficiently detect tumor-reactive T cells in the blood. In addition, TCRs are antigen-specific, meaning that different TCRs are required for different (sub)cancer types. The aim of project PrioriTCR is to develop an immunoinformatics platform that simplifies and accelerates the identification of potent TCRs. This proof-of-concept project is designed for the Wilms' Tumor 1 (WT1) antigen, which is overexpressed in a variety of solid tumors and blood cancers. WT1 is considered a virtually universal cancer marker, promising to target with specific immunotherapy. By combining limited laboratory experiments with blood samples from cancer patients with artificial intelligence, this project will result in the identification of new candidate potent WT1-specific TCRs for development of next-generation T-cell therapies. The developed computer models can be further extended for TCRs against other cancer markers.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Laukens Kris
• Co-promoter: Meysman Pieter

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

The traditional process of designing and developing vaccines has been challenged dramatically by the COVID-19 pandemic, with the adoption of mRNA-based vaccines and a reduction of lengthy development pipelines from 10-15 years to 1-1.5 years. This creates a push for further innovation in vaccine development, in particular for diseases with a high unmet need. As an example, mortality due to rabies (a lyssavirus) remains unacceptably high. Although safe, effective vaccines are available for human and animal use, human vaccines are too expensive and generally inaccessible for widespread use in regions where the risk of bites from rabid animals is highest. mRNA approaches offer an opportunity to provide affordable vaccines with the possibility of manufacturing in low and middle income countries, with optimised design affording broader protection. The aim of such an approach would be to drive down cost and broaden supply and equity of access. Novel in silico approaches such as those analysing the T cell receptor response may permit insights into the immune response elicited by rabies vaccines, aid understanding of the mode of action and guide future use. The objective of the current project is to investigate if detailed analysis of the T-cell receptor response can be valuable to inform vaccine design and improve the vaccine development process, using a rabies mRNA vaccine as a proof-of-concept. We will combine in vitro (UAntwerp) and in silico (ImmuneWatch) techniques to gain insights into the T cell response against a range of experimental rabies mRNA vaccine constructs (Quantoom). The project is a public-private partnership aiming to explore novel approaches in vaccine development and to prepare future collaborations between the project partners.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Ogunjimi Benson

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Hematologic malignancies are cancers that primarily affect the blood, bone marrow and lymph nodes. Among the different subtypes, B-cell non-Hodgkin lymphoma (B-NHL) and Acute Myeloid Leukemia (AML) are the most prevalent indications. Common to both indications, alterations in the Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway are frequently observed, leading to constitutive activation and oncogenic signalling. Known key effectors within the pathway such as Bruton's tyrosine kinase (BTK), interleukin-1 receptor associated kinases (IRAKs), Myeloid differentiation primary response 88 (MYD88), and Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) represent promising therapeutic targets for these indications and have been at the center of significant drug discovery efforts. In order to tackle common limitations associated to canonical small molecule inhibitors (SMI) (e.g., resistance mutations, lack of response due to scaffolding functions, …), this project is aimed at exploring the therapeutic potential of selective target degradation through PROteolysis-TArgeting Chimera (PROTAC). PROTAC represents an innovative protein degradation technology able to induce protein degradation by taking advantage of the ubiquitin proteasome pathway. The goal of the project is to provide a better understanding of the therapeutic potential of PROTACs specific for BTK, IRAK1 and IRAK4 in comparison to their respective SMI counterparts. To this end, we will evaluate the molecular and functional consequence of target degradation or inhibition in relevant models of AML and B-NHL as well as reflect the work on AML primary patient material. In addition, potential synergistic activity between PROTACs and clinically relevant SOC/SMIs options will be evaluated. Last, potential on-target/off-tumor activity in immune cell sub-types in which the NF-kB pathway is known to play a role (e.g., T-cells) will be evaluated.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Anguille Sébastien
• Fellow: Suls Toon

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

In the past five years, RNA therapeutics have witnessed a true revolution. Several RNA-based therapies have been approved for the treatment of genetic diseases, with unprecedented successes, as in spinal muscular atrophy. Moreover, the past year showed the world that RNA-based therapies, namely mRNA vaccines, can be the answer to a worldwide pandemic and save the lives of millions. RNA therapies are however lagging behind in clinical oncology. The overarching aim of this multi-armed project is to develop RNA-based cancer treatments. In parallel, the development of immune checkpoint inhibitors has revolutionized cancer care, but its success remains limited to a subset of patients. Altogether, for 60 percent of the eight million new cancer patients diagnosed in Europe each year, including almost all children with solid tumors, there is no EMA- or FDA-approved immunotherapy option, and they are left out of the circle of hope. In response, CANCERNA aims to build on these two breakthroughs and apply RNA-based therapeutics to overcome key barriers to unfold successful anti-cancer immune responses. Our two key objectives are: on one hand, harness the modulation of RNA processing to enhance the accessibility and immune susceptibility of the tumour and its microenvironment. While on the other hand, enhance the activity of the immune system by retargeting immune effector cells and developing personalized mRNA vaccines. The project will focus on two cancer types: acute myeloid leukemia and uveal melanoma. The collective knowledge of our consortium of RNA scientists, clinicians and biotech-pharma experts in RNA processing, RNA drug design and delivery, biocomputing and immuno-oncology provides a unique opportunity to significantly advance novel RNA technologies into successful cancer therapies.

Researcher(s)

• Promoter: Smits Evelien
• Co-promoter: De Waele Jorrit
• Co-promoter: Lion Eva
• Co-promoter: Pauwels Patrick
• Co-promoter: Siozopoulou Vasiliki
• Co-promoter: Van Audenaerde Jonas

Research team(s)

• Center for Oncological Research (CORE)

Project website

Project type(s)

• Research Project

Abstract

Flow cytometry is a widely used technique that allows the simultaneous and multi-parameter analysis of physical and biochemical characteristics of a population of living cells or particles in a heterogenous sample. The Laboratory of Experimental Hematology (LEH) has 20+ years of demonstrable experience in flow cytometry (200+ published manuscripts), as well as experience in guidance and support of both internal and external research groups with flow cytometric experiments (30+ joint manuscripts). With this application, we now aim to maintain and expand a flow cytometry and cell sorting core facility at the AUHA. The ambition of LEH is to make basic and advanced flow cytometry available for all active and prospective users at the AUHA in order: (i) to leverage qualitative cell biological and (pre)clinical cellular research, (ii) to provide qualitative education covering flow cytometry and its applications over multiple faculties (FGGW, FBD and FWET), and (iii) to provide external service using flow cytometry as a basis, both intellectually as well as practically.

Researcher(s)

• Promoter: Cools Nathalie
• Co-promoter: Anguille Sébastien
• Co-promoter: Lion Eva
• Co-promoter: Ponsaerts Peter

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Acute myeloid leukemia (AML) is one of the most common leukemias in adults with a 5‐year overall survival rate of only 30%. Despite therapeutic advances in the last decade, novel adoptive T-cell immunotherapies using anti-tumor chimeric antigen receptors (CARs) and T-cell receptors (TCRs) are not fully developed for AML. Moreover, expression of immunosuppressive immune checkpoints (IICPs) hinder the success of these T-cell therapies. To address this issue, the aim of this project is to develop an innovative multi-epitope Wilms' tumor 1 (WT1)-specific TCR, CD200-specific non-signaling chimeric antigen receptor (NSCAR) and IICP-disrupted (mulTplex)-engineered adoptive T-cell therapy for AML. We will combine TCRs with different human leukocyte antigen (HLA) restrictions and specificities against diverse epitopes of WT1, a key intracellular antigen, in a multi-epitope strategy. To avoid the interaction between native and introduced TCRs, native TCRs will be disrupted by CRISPR-Cas9 technology. The NSCAR, which lacks the typical CAR's signaling domain, will act as an "anchor" for the T cells by locking onto AML cells through CD200, a novel extracellular AML antigen, and without triggering T-cell activation. By doing so, we expect to improve TCR-mediated anti-AML cytotoxic capacity of mulTplex-engineered T cells. To further harness the anti-leukemic activity of engineered T cells, AML-associated IICPs will also be disrupted using CRISPR-Cas9 methods. Both in vitro and in vivo evaluation of mulTplex-engineered T cells will ensure translation of our innovative combinatorial approach into clinical studies.

Researcher(s)

• Promoter: Lion Eva
• Fellow: Flumens Donovan

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Confidential .

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Anguille Sébastien
• Co-promoter: Berneman Zwi

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

VAXINFECTIO-PD is an established Industrial Research Fund (IOF) consortium, well equipped to build an ecosystem offering research, valorisation, innovation and development to answer existing and new challenges in the field of infectious diseases and vaccinology. These domains fall within one of the valorisation domains of the Antwerp University, and the newly established business unit Antwerp Valorisation & Development (AVD) of the UAntwerp. The VAXINFECTIO-PD consortium built up a unique and extensive track record through research, services, spin-off creation and innovative pathways, in generating product concepts/prototypes and research platforms that form the basis of medical innovation. The various core research units have had an important international image in the recent years with publications in leading journals, coordination of several European projects, as well as active presence and involvement in international scientific and policy forums. For the 6-year period the IOF-consortium will further focus on 5 interlinked valorisation avenues, all creating or guaranteeing growth on the parameters P3, P4, P5 and P6: translational vaccination platform for improved and new preventive and therapeutic vaccines, prognostic and diagnostic platforms, core facilities (for cellular vaccines, human challenge studies and biobanks), infectious disease and immune modelling and prediction, and improved vaccine delivery and medical devices through product development.

Researcher(s)

• Promoter: Van Damme Pierre
• Co-promoter: Beutels Philippe
• Co-promoter: Cools Nathalie
• Co-promoter: Hens Niel
• Co-promoter: Lion Eva
• Co-promoter: Malhotra Surbhi
• Co-promoter: Verwulgen Stijn
• Co-promoter: Vorsters Alex
• Fellow: Bamberger Martina

Research team(s)

• Centre for the Evaluation of Vaccination (CEV)

Project type(s)

• Research Project

Abstract

Chimeric antigen receptor (CAR)-T cell therapy has demonstrated unprecedented clinical activity in patients with hematological diseases, but a large proportion of them will ultimately relapse. Further optimization of this new treatment modality is therefore required to unlock its full therapeutic potential. In this project, in addition to using readily available cell line models, we will use our mRNA electroporation technology for CAR loading of immune cells. This will provide a rapid and efficient way to explore new research paths that can lead to optimized CAR-based cellular therapies for hematological diseases. Will assess the value of a multi-targeted approach incorporating two established CAR targets (CD19 and B-cell maturation antigen) and the novel CAR candidate CD200. Next, the hinge and co-stimulatory domains in the CAR structures will be sequentially modified, comparing conventional hinge and co-stimulatory domains with our recently discovered 4-1BB-hinge and CD26 co-stimulatory domains. Exhaustion will be prevented by introducing programmed death (PD-1) silencing RNA in the CAR-modified cells to reduce PD-1-mediated co-inhibitory signaling. Finally, positive findings will be translated from our cell line models to conventional T cells, NK cells and gdT cells.

Researcher(s)

• Promoter: Anguille Sébastien
• Co-promoter: Lion Eva
• Fellow: Roex Gils

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Based on the strong need for more targeted, tolerable and durable treatment strategies that could postpone or even prevent recurrence of disease in the most common adult malignant brain tumor, we embarked on a phase I/II clinical trial assessing frontline treatment with autologous dendritic cell (DC) vaccines loaded with glioblastoma-associated tumor antigen Wilms' tumor 1 in conjunction with conventional chemoradiation following surgery in adults with glioblastoma multiforme (GBM; NCT02649582). Childhood high-grade glioma (HGG, including GBM) and diffuse intrinsic pontine glioma (DIPG) are rare aggressive brain tumors. In the absence of a standard of care, treatment is mostly adapted from adult schedules, resulting in 5-year survival rates of less than 5% and 1% after diagnosis, respectively. With limited advanced investigational treatment options for this vulnerable patient population, we strive to extend our clinical study to the pediatric application. Ultimately working towards the clinical valorization of an adjuvant DC-based immunotherapy approach, health care evaluation is warranted. To this extent, we will include collection of patient-reported outcome on how the study therapy is experienced throughout time in the response evaluation of all study patients. As the search for biomarkers is gaining momentum in the rapidly evolving cancer immunotherapy landscape, we are also continuously expanding the screening assays on clinical patient material. The present project proposal is designed to allow completion of the intended adult GBM patient recruitment number and to extend the trial, innovating on the pediatric application of DC vaccination, health care evaluation and emerging therapeutic biomarker research. Within the context of hard-to-treat brain tumors, this study and its specific design will add a new dimension to our translational and clinical DC vaccine programs by investigating whether DC vaccination can be combined with first-line chemoradiation treatment of adult GBM and childhood HGG and DIPG patients and whether this combination leads to tumor-specific immune responses and improved survival. Exploration of patient-reported outcomes will help to improve symptom management, functional status and overall quality of life and will provide necessary information for future clinical valorization of this type of personalized medicine. In depth research on clinically valuable biomarkers will allow us to make a significant contribution to the broader (immunotherapy-oriented) scientific community.

Researcher(s)

• Promoter: Berneman Zwi
• Co-promoter: De Praeter Mania
• Co-promoter: Lion Eva
• Co-promoter: Norga Koenraad
• Co-promoter: Peeters Marc
• Co-promoter: Smits Evelien

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Improvement of first-line treatment for cancer patients with a high tumor recurrence rate and low effective treatment options, such as pancreatic cancer (PC), is warranted. Pancreatic cancer is a devastating disease with a 5-year survival rate below 5%, depending on the specific stage of disease when it is diagnosed, rendering it the 4th most common cause of cancer-related death worldwide. Even those who are eligible for curative-intent resection and conventional adjuvant treatment will nearly all die of their disease due to the high tendency towards recurrence. Adjuvant treatment with gemcitabine after resection of PC decreases recurrence rate, but the disease-free survival of these patients stays dismal with a 5-year survival rate below 21%, underscoring the need for new adjuvant regimens. The combination of gemcitabine with immunotherapy might improve outcome as suggested by some studies, but available data is so far limited to a few early-phase uncontrolled clinical trials. Interleukin (IL)-15-transpresenting dendritic cells (DCs) are a promising armament for immunotherapy of PC. Complementary to current treatments, DCs as quintessential antigen-presenting cells of the immune system can activate the antitumor immune system to attack pancreatic cancer cells. Preclinical data demonstrate the therapeutic potential of these innovative IL-15-transpresenting DCs evidenced by superior activation of the antitumor immune system to attack cancer cells. Since this will be the first-in-human use of IL-15-transpresenting DCs, the objectives are to test the safety, feasibility and immunopotency in patients with refractory solid tumors, the prototypic cancer patient population for phase I trials. This phase I clinical study is pivotal for future testing of this promising IL-15-transpresenting DC vaccine as adjuvant therapy to current anticancer regimens aiming to improve the standard of care of cancer patients with a high unmet medical need.

Researcher(s)

• Promoter: Berneman Zwi
• Co-promoter: Lion Eva
• Co-promoter: Peeters Marc
• Co-promoter: Smits Evelien

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Chimeric antigen receptor (CAR)-T-cell therapy has achieved remarkable clinical response rates in relapsed/refractory B-cell malignancies. Unfortunately, the frequency of relapse remains high as a result of decreased cellular fitness, poor anti-tumor activity or a lack of persistence of the CAR-T-cell product. While the CAR architecture is a foundational driver of CAR-T-cell responses, its design is poorly understood, in particular for the structural hinge domain. Current hypothesis-driven workflows are low in throughput, expensive and laborious, and complicate pattern recognition. This project aims to define CAR hinge domain design rules by studying the relationship between hinge properties and CAR-T-cell responses in the context of hematological malignancies. We employ high-throughput cellular assays to phenotypically and functionally evaluate a large library of novel hinge domain candidates. A machine learning algorithm will be trained to correlate hinge domain characteristics with the obtained cellular outputs. We anticipate to create an algorithm that is capable of predicting superior hinge domains from a naïve set of candidates against a multitude of target antigens. We envision that in the future this model can be further trained to include other CAR domains and domain combinations to assist in further personalization of CAR-T-cell therapy.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

The aim of this project is to develop a robust workflow and to identify promising T-cell receptors (TCRs) for the development of T cell-based immunotherapies, focusing on the leukemia-associated antigen Wilms' tumor-1 (WT1). For this, a unique collection of blood samples is available from acute myeloid leukemia (AML) patients in the context of our academic clinical trials investigating WT1-loaded dendritic cell (DC) vaccination, a cellular immunotherapy designed to activate WT1-specific T cells. By combining specialized cell sorting techniques with in-house developed bioinformatic tools, single-cell TCR and RNA sequencing will be integrated with cutting-edge computational models to link the specificity and transcriptomic profile of these T cells with patients' clinical responses.

Researcher(s)

• Promoter: Laukens Kris
• Co-promoter: Lion Eva
• Co-promoter: Meysman Pieter
• Fellow: Gielis Sofie

Research team(s)

• ADReM Data Lab (ADReM)

Project type(s)

• Research Project

Abstract

Genetic engineering of lymphocytes for adoptive cell transfer has marked a turning point in personalized immunotherapy, especially in the treatment of cancer. Adoptive T-cell immunotherapies using antitumor chimeric antigen receptors (CARs) and T-cell receptors (TCRs) have, however, not met expectations yet for the majority of malignancies, including acute myeloid leukemia (AML). Moreover, expression of immunosuppressive immune checkpoints (IICPs) hinders the success of these therapies. To address the shortcomings of current T-cell therapies, the aim of this research project is to develop an innovative combinatorial and genetically engineered adoptive T-cell therapy focusing on AML as a disease model. In this project four important issues will be covered. First, cancer cells capitalize on processes such as downregulating peptide-major histocompatibility complex (pMHC) ligands to lower their immunogenicity and, by doing so, evade immune detection. Second, TCRs that target tumor self-antigens are scarce and usually have low affinities, having difficulties in binding target tumor antigens. Finding ways to improve interaction between pMHC ligands and low affinity TCRs, such as those that target self-antigens, would improve the chance of success in TCR-engineered T-cell therapies. Third, adoptive T-cell therapies are confronted with immunosuppressive environments that hinder their efficacy via engagement of IICPs, such as PD-1, TIM-3, or LAG-3. Determining the most relevant IICPs is key for developing effective adoptive T-cell therapies. Fourth, these therapies must be tumor-specific and efficacious once translated into a clinical setting. Taken together, combinatorial and flexible approaches for TCR-engineering will mark the next-generation of T-cell immunotherapies, by addressing (a) improved interaction between T cells and cancer cells, (b) immune evasion through IICPs, (c) cost-effectiveness of an all-in-one therapy, and (d) safety using RNA-based methods. In summary, improved adoptive T-cell therapies that overcome CAR and TCR challenges as well as the immunosuppressive environment that hinders antileukemic T-cell action will facilitate innovative solutions for cancer treatment.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Anguille Sébastien
• Fellow: Flumens Donovan

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project website

Project type(s)

• Research Project

Abstract

Acute myeloid leukemia (AML) is a rare type of cancer that predominantly affects people in the third age. The 5‐year overall survival rate of AML patients is only 30%, a figure that has not substantially changed despite enormous therapeutic advances in the last decade. Novel immunotherapies, such as T-cell receptor (TCR) T-cell and chimeric antigen receptor (CAR) T-cell therapies, are difficult to adopt in the context of AML. This is because most AML-related antigens are intracellular self-antigens that are expressed on the AML cell surface as peptides via major histocompatibility complexes (MHC); TCRs specific for these self-antigens are difficult to obtain since self-reactive T cells undergo thymic negative selection. In contrast to CD19 which is a very suitable extracellular target antigen for CAR-T cell therapy in acute lymphoblastic leukemia (ALL), the very few extracellular antigens expressed on AML cells that can serve as targets for CAR-T cell-based therapies, such as CD33 and CD123, are also expressed on normal hematopoietic stem/progenitor cells entailing a risk of intolerable myeloablation. The aim of this innovative project is to combine the best of two worlds, namely to redirect T-cells towards the key intracellular AML antigen Wilms' tumor protein 1 (WT1) using WT1-specific TCRs, combined with an innovative non-signaling CAR (NSCAR) towards a novel candidate extracellular AML antigen.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Anguille Sébastien
• Co-promoter: Campillo Davó Diana

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Acute myeloid leukemia (AML) is a rare type of cancer that predominantly affects people in the third age. The 5‐year overall survival rate of AML patients is only 30%, a figure that has not substantially changed despite enormous therapeutic advances in the last decade. Novel immunotherapies, such as T-cell receptor (TCR) T-cell and chimeric antigen receptor (CAR) T-cell therapies, are difficult to adopt in the context of AML. This is because most AML-related antigens are intracellular self-antigens that are expressed on the AML cell surface as peptides via major histocompatibility complexes (MHC); TCRs specific for these self-antigens are difficult to obtain since self-reactive T cells undergo thymic negative selection. In contrast to CD19 which is a very suitable extracellular target antigen for CAR-T cell therapy in acute lymphoblastic leukemia (ALL), the very few extracellular antigens expressed on AML cells that can serve as targets for CAR-T cell-based therapies, such as CD33 and CD123, are also expressed on normal hematopoietic stem/progenitor cells entailing a risk of intolerable myeloablation. The aim of this innovative project is to combine the best of two worlds, namely to redirect T-cells towards the key intracellular AML antigen Wilms' tumor protein 1 (WT1) using WT1-specific TCRs, combined with an innovative non-signaling CAR (NSCAR) towards a novel candidate extracellular AML antigen.

Researcher(s)

• Promoter: Lion Eva
• Co-promoter: Campillo Davó Diana

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

COVID-19 is a disease caused by an infectious outbreak of SARS-CoV-2. This viral SARS-CoV-2 infection can present itself in a broad spectrum of clinical features, ranging from asymptomatic, sensation of a mild cold or flu to severe bilateral pneumonia and death. Cancer patients are at high risk to develop serious illness after infection with SARS-CoV-2. Therefore, it is of high importance to protect these patients by following hygiene measurements and social distancing. But, as indicated by the guidelines of the Belgian and European Society for Medical Oncology, it is also important to vaccinate cancer patients. Although, not many studies that elevated the vaccine efficacy of COVID-19 vaccines in cancer patients have been performed. Due to the cancer or the treatment, it could be possible that the efficacy of the vaccines is lower in cancer patients or that they develop more side effects as a result of vaccination. To investigate this, we will monitor the reaction of the immune system of current and ex oncological and haematological patients on the different COVID-19 vaccines (Pfizer, Moderna, AstraZeneca, Janssen Pharmaceutica). The adverse effects as a reaction on vaccination will be investigated in this population as well. Clinical data of the patients will be collected and a blood drawn will be performed at different time points: before vaccination and 4, 6 and 12 months after receiving the first vaccination dose. The primary endpoint of the study is the quantification of different anti SARS-CoV-2 specific IgG antibodies per study cohort at 4 months after the first vaccination. The secondary endpoints of the study are to measure the SARS-Cov-2 specific T cell response and to investigate the evolution and duration of the cellular immune response after vaccination in the patient cohort. Another secondary endpoint is to analyse the titers of neutralizing antibodies both 4,6 and 12 months after receiving the first vaccination dose. Furthermore, it is aimed to investigate the efficacy of the immune response in the patient cohort for each different vaccine. This will be assessed by the SARS-CoV-2 infection rate based on information collected through questionnaires on incidence of (PCR-confirmed or chest CT scan confirmed) SARS-CoV-2 infection within a time frame of 12 months after the start of the study. At last, we will investigate the safety of the different COVID-19 vaccines that are commercially available in Belgium. Safety will be reported in terms of incidence and severity of adverse effects (AEs) using a questionnaire. Patients will be asked to report their adverse events over a period of 3 days after the vaccination day. This research project will provide knowledge on how the immune reaction after vaccination develops in cancer patients and patients with oncological or haematological history. The team of prof Lion of the Laboratory of Experimental Hematology, focusses on the SARS-Cov-2 specific cellular immunity research.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Mathematical simulation models have become indispensable tools for forecasting and studying the effectiveness of intervention strategies such as lockdowns and screening during the SARS-CoV-2 pandemic. Estimation of key modeling quantities uses the serological footprint of an infection on the host. However, although depending on the type of assay, SARS-CoV-2 antibody titers were frequently not found in young and/or asymptomatic individuals and were shown to wane after a relatively short period, especially in asymptomatic individuals. In contrast, T-cells have been found in different situations – also without antibodies being present - ranging from convalescent asymptomatic to mild SARS-CoV-2 patients and their household members, thereby indicating that T-cells offer more sensitivity to detect past exposure to SARS-CoV-2 than the detection of antibodies can. In this project, we will gather on a population level T-cell and antibody SARS-CoV-2 specific data from different well-described cohorts including 300 individuals (and 200 household members) who have had proven covid-19 infection > 3 months earlier, 100 general practitioners, 100 hospital workers, 500 randomly selected individuals and 75 pre-covid-era PBMC/sera. This data will be used in comparative simulation models and will lead to a reassessment of several key epidemiological estimates such as herd immunity and the reproduction number R that will significantly inform covid-19 related public health interventions.

Researcher(s)

• Promoter: Ogunjimi Benson
• Co-promoter: Beutels Philippe
• Co-promoter: Coenen Samuel
• Co-promoter: Laukens Kris
• Co-promoter: Lion Eva
• Co-promoter: Meysman Pieter
• Co-promoter: Van Damme Pierre

Research team(s)

• Centre for Health Economics Research and Modelling of Infectious Diseases (CHERMID)

Project type(s)

• Research Project

Abstract

Can the bioinformatics R package FlowSOM – for high-dimensional single-cell flow cytometry datasets – assist research on dendritic cell-mediated immune cell activation? The primary objective of this Small Project is to evaluate the R package FlowSOM for the analysis of high-dimensional flow cytometry data and to explore its use in the preclinical and clinical evaluation of immunogenicity of next-generation anticancer dendritic cell vaccine candidates that are currently under investigation at the Laboratory of Experimental Hematology (UAntwerp) and the Center for Cell Therapy and Regenerative Medicine (Antwerp University Hospital). With increasing dimensionality of biological data and technical advances, manual flow cytometry data analysis will become inadequate. Applying bioinformatics, automated and unbiased comparisons between in vitro/ex vivo-stimulated immune effector cells with novel dendritic cell vaccine candidates will assist further development of potent dendritic cell preparations with the most superior immune-stimulating capacities and will be essential in unraveling therapy responsive immune profiles in longitudinal studies. FlowSOM is a powerful algorithm that builds self-organizing maps (SOMs) to provide an overview of marker expression on all cells and reveal cell subsets that could be overlooked with manual gating. Ultimately, our aim is to develop an advanced immune profiling platform for evaluation of preclinical and clinical dendritic cell-mediated immune responses.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Improvement of frontline treatment for cancer patients with a high tumor recurrence rate and low effective treatment options is warranted. Dendritic cell (DC) vaccination is in this context a promising immunotherapeutic armament. Complementary to current treatments, DCs as quintessential antigen-presenting cells of the immune system, can activate the antitumor immune system to attack cancer cells. We previously established novel monocyte-derived DC generation protocols integrating the pleiotropic immune regulator interleukin (IL)-15 while downmodulating ligands for the inhibitory checkpoint programmed death (PD)-1. Our preclinical data demonstrate high therapeutic potential of these designer DCs, evidenced by superior immunogenic capacities. Further extending our DC immunotherapy program, this project is designed to enable the first-in-human clinical application of our novel designer DC vaccines, allowing development of clinical-grade production processes, human in vivo safety and feasibility testing and design of next-level combinatorial therapy approaches for cancer patients with a high unmet medical need.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Currently therapeutic cancer vaccines have taken center stage in cancer immunotherapy. Such cancer vaccines are designed to delay or prevent cancer relapse after standard treatment with chemotherapy or radiotherapy, and to attack distant metastatic cancer cells. We have already successfully tested a personalized cell-based cancer vaccine for leukemia patients and we demonstrated that the vaccine could prevent leukemia relapse in about 35% of the vaccinated leukemia patients. This cancer vaccine consists of specially cultured immune cells of the patient that upon injection in the skin starts off an anti-tumor immune response against residual or chemotherapy-resistant leukemia cells. In this project we aim to make this personalized leukemia vaccine even more powerful in the test tube by innovative manipulations and by implementing new emerging anti-cancer strategies that have already proven successful in solid tumors.

Researcher(s)

• Promoter: Van Tendeloo Vigor
• Co-promoter: Lion Eva
• Fellow: Versteven Maarten

Research team(s)

• Laboratory for Experimental Hematology (LEH)

Project type(s)

• Research Project

Abstract

Given their potential to stimulate both adaptive and innate anti-tumor immune responses, dendritic cells (DCs) are subject of intense examination as pharmacological tools for cancer immunotherapy. A growing body of evidence indicates that DC vaccination can be of clinical benefit to cancer patients, encouraging the further development of this therapy. Nevertheless, there is a general agreement among cancer researchers that the true clinical potential of DC-based cancer immunotherapy has not been attained yet. New DC generation protocols that boost their immunogenic properties may provide an improved clinical benefit for patients, by a more powerful activation of T cells and natural killer (NK) cells. In this context, two novel monocyte-derived DC generation protocols resulting in highly immune stimulatory DCs have been developed in vitro, focusing on (i) the use of interleukin (IL)-15 during the differentiation process (so-called IL-15 DCs, developed in the Laboratory of Experimental Hematology of the University of Antwerp), and (ii) inhibition of programmed death-1 (PD-1) activation by downregulating its ligands PD-L1 and PD-L2 with silencing RNA (developed by the collaborating group of Dolstra, Nijmegen, The Netherlands). In this project, we hypothesize that integrating PD-L silencing in our IL-15 DCs will result in superior stimulatory potential. Aiming at leveraging full force of both adaptive and innate anti-tumor immunity with DC vaccination, the objective of this study is to corroborate on the effects of PD-L silencing in IL-15 DCs regarding their T cell-specific and NK cell stimulatory potential by aggregating different established techniques. The results of these experiments will reveal the potential added value of incorporating intrinsic PD/PD-L axis blockade in our novel IL-15 DC vaccine and are likely to bring forward innovative elements that could further help optimize the clinical protocols of our DC vaccine trials.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

Project type(s)

• Research Project

Abstract

Detrimental inflammatory responses in the central nervous system (CNS) are a hallmark of various neurodegenerative pathologies, with multiple sclerosis (MS) and stroke/trauma being excellent examples demonstrating the highly complex interplay between CNS resident microglia and lesion infiltrating leucocytes. Lesion-associated inflammatory responses, both in the acute as well as in the chronic phase, are classified as being highly pro-inflammatory. In this context, it is generally believed that a functional conversion of a pro-inflammatory type M1 microglia/macrophage phenotype, which can readily be detected in severe CNS inflammatory lesions, into a type M2a immune modulating microglia/macrophage phenotype can have a beneficial effect on disease outcome. Using our extensive experience with cell implantation into the CNS of mice, our current research aims at in vivo modulation of neuro-inflammatory responses by intracerebral implantation of mesenchymal stem cells (MSCs) genetically engineered to express interleukin (IL)13, a potent inducer of the M2a phenotype in macrophages. Thus far, we have demonstrated in the cuprizone (CPZ) mouse model of CNS inflammation and demyelination that microglial quiescence and subsequent protection against demyelination coincides with the appearance of M2a-polarised macrophages in the CNS following grafting of IL13-expressing MSCs. Continuing our research, this PhD project will focus on unravelling the in vivo signalling events that lead to IL13-mediated induction of the M2a macrophage phenotype within MSC graft-infiltrating macrophages in the CNS, as well as the cellular interactions by which these M2a macrophages can influence the development of microglia/macrophage-mediated neuro-inflammation in the CNS. Upon completion we hope to: (i) further elucidate the immunological consequences of MSC grafting in the CNS, and (ii) provide pre-clinical rationale for the use of IL13 as an immune modulating cytokine in the CNS.

Researcher(s)

• Promoter: Ponsaerts Peter
• Co-promoter: Lion Eva
• Co-promoter: Praet Jelle
• Fellow: Quarta Alessandra

Research team(s)

Project type(s)

• Research Project

Abstract

Human blood contains several immune-competent cells including cells of the innate and adaptive immune system. Over the past years, the phenotypic and functional boundaries distinguishing the main cell subsets of the immune system have become increasingly blurred. While it has been already established that T cells may share some phenotypic and functional features of natural killer (NK) cells, more recent evidence points to the existence of such overlap between NK cells and dendritic cells (DCs). Both NK cells bearing DC markers and antigen-presenting capacity and DCs expressing NK-related molecules and having cytotoxic functions have been described. In view of this, CD56, a prototypic marker of NK cells, was found to be expressed on DC derived from monocytes exposed to interleukin-15. We demonstrated that these IL15-DC were endowed with superior stimulatory and unique cytotoxic properties (killer DC). The aim of this project is to identify and characterize in detail the in vivo counterpart of these CD56+ killer DCs in human blood. Particular emphasis will be given to the reciprocal interactions of myeloid CD56+ DC-like cells with CD56+ innate lymphocytes (NK and NKT cells, γδ T cells) in the presence or absence of immunomodulatory molecules. Next, the capacity of CD56+ blood DCs to stimulate both innate and adaptive cell responses will be analyzed in a human acute myeloid leukemia (AML) model as a first step towards design of next-generation therapeutic AML vaccines.

Researcher(s)

• Promoter: Van Tendeloo Vigor
• Co-promoter: Lion Eva
• Fellow: Campillo Davó Diana

Research team(s)

Project type(s)

• Research Project

Abstract

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

Researcher(s)

• Promoter: Van Tendeloo Vigor
• Co-promoter: Lion Eva
• Fellow: Van Acker Heleen

Research team(s)

Project type(s)

• Research Project

Abstract

The concomitant activation of dendritic cells (DC) and natural killer (NK) cells is an attractive modality for immune-based therapies. Inducing immunogenic cell death to facilitate tumor cell recognition and phagocytosis by neighbouring immune cells is of utmost importance for guiding the outcome of an immune response. The aim of this project is to study the mechanisms that enhance the immunogenicity of tumor cells, using acute myeloid leukemia (AML) as tumor model, in order to increase the immunostimulatory potential of NK cells and DC and to promote their cross-talk and subsequent T cell stimulating capacity. The goal is to determine the conditions generating the most potent antileukemic immune response. We previously reported that AML cells in response to electroporation with the synthetic double-stranded RNA poly(I:C) exert improved immunogenicity, demonstrated by enhanced DC- and NK cell-activating capacities, supporting the use of poly(I:C) as a cancer vaccine component to provide a way to overcome immune evasion by leukemic cells. Here, we will further investigate potential mechanisms of the improved susceptibility of poly(I:C)-electroporated AML cells to DC and NK cell functions. This could lead to the determination of a phenotype that renders tumor cells more susceptible to NK cell and DC recognition. This project comprises human in vitro research on how tumor cells can be modified to promote NK cell and DC activity for the development of immunotherapy for leukemia.

Researcher(s)

• Promoter: Lion Eva

Research team(s)

Project type(s)

• Research Project

Abstract

In this project we will investigate the influence of acute myeloid leukemia cells loaded with Toll-like receptor (TLR) ligands on the activation of dendritic cells (DCs) and natural killer (NK) cells. The hypothesis is that leukemia cells loaded with TLR ligands are capable of activating the recently discovered helper function of NK cells, so these NK cells can effectuate the polarization of immature DCs to T helper type 1 (Th1)-polarised DCs (DC1NK). This cross-talk between the innate and adaptive immune system in which DC1NK play a central role, would then facilitate the activation of antigen-specific Th1 cells and cytotoxic T lymphocytes.

Researcher(s)

• Promoter: Berneman Zwi
• Fellow: Lion Eva

Research team(s)

Project type(s)

• Research Project

Abstract

In this project we will investigate the influence of acute myeloid leukemia cells loaded with Toll-like receptor (TLR) ligands on the activation of dendritic cells (DCs) and natural killer (NK) cells. The hypothesis is that leukemia cells loaded with TLR ligands are capable of activating the recently discovered helper function of NK cells, so these NK cells can effectuate the polarization of immature DCs to T helper type 1 (Th1)-polarised DCs (DC1NK). This cross-talk between the innate and adaptive immune system in which DC1NK play a central role, would then facilitate the activation of antigen-specific Th1 cells and cytotoxic T lymphocytes.

Researcher(s)

• Promoter: Berneman Zwi
• Fellow: Lion Eva

Research team(s)

Project type(s)

• Research Project