Kidney transplantation is the best treatment option for patients with kidney failure. Unfortunately many patients lose their allograft due to (chronic) rejection. Rejection is caused by the immune... Show moreKidney transplantation is the best treatment option for patients with kidney failure. Unfortunately many patients lose their allograft due to (chronic) rejection. Rejection is caused by the immune reaction of the recipient against the donor’s human leukocyte antigens (HLA). While traditional kidney allocation is based on HLA matching on the antigen level, matching on the epitope level could be more feasible. Furthermore, epitope mismatch analysis could be used for post-transplant risk stratification, enabling the personalisation of immunosuppressive treatment for kidney transplant recipients. In this thesis, the basic science and clinical application of HLA epitopes in kidney transplantation are discussed. Show less
Olesen, H.G.; Michailidou, I.; Zelek, W.M.; Vreijling, J.; Ruizendaal, P.; Klein, F. de; ... ; Baas, F. 2022
Damage and disease of nerves activates the complement system. We demonstrated that activation of the terminal pathway of the complement system leads to the formation of the membrane attack complex ... Show moreDamage and disease of nerves activates the complement system. We demonstrated that activation of the terminal pathway of the complement system leads to the formation of the membrane attack complex (MAC) and delays regeneration in the peripheral nervous system. Animals deficient in the complement component C6 showed improved recovery after neuronal trauma. Thus, inhibitors of the MAC might be of therapeutic use in neurological disease. Here, we describe the development, structure, mode of action, and properties of a novel therapeutic monoclonal antibody, CP010, against C6 that prevents formation of the MAC in vivo. The monoclonal antibody is humanized and specific for C6 and binds to an epitope in the FIM1-2 domain of human and primate C6 with sub-nanomolar affinity. Using biophysical and structural studies, we show that the anti-C6 antibody prevents the interaction between C6 and C5/C5b by blocking the C6 FIM1-2:C5 C345c axis. Systemic administration of the anti-C6 mAb caused complete depletion of free C6 in circulation in transgenic rats expressing human C6 and thereby inhibited MAC formation. The antibody prevented disease in experimental autoimmune myasthenia gravis and ameliorated relapse in chronic relapsing experimental autoimmune encephalomyelitis in human C6 transgenic rats. CP010 is a promising complement C6 inhibitor that prevents MAC formation. Systemic administration of this C6 monoclonal antibody has therapeutic potential in the treatment of neuronal disease. Show less
Purpose Aberrantly expressed glycans in cancer are of particular interest for tumor targeting. This proof-of-conceptin vivostudy aims to validate the use of aberrant Lewis glycans as target for... Show morePurpose Aberrantly expressed glycans in cancer are of particular interest for tumor targeting. This proof-of-conceptin vivostudy aims to validate the use of aberrant Lewis glycans as target for antibody-based, real-time imaging of gastrointestinal cancers. Procedures Immunohistochemical (IHC) staining with monoclonal antibody FG88.2, targeting Lewis(a/c/x), was performed on gastrointestinal tumors and their healthy counterparts. Then, FG88.2 and its chimeric human/mouse variant CH88.2 were conjugated with near-infrared fluorescent (NIRF) IRDye 800CW for real-time imaging. Specific binding was evaluatedin vitroon human gastrointestinal cancer cell lines with cell-based plate assays, flow cytometry, and immune-fluorescence microscopy. Subsequently, mice bearing human colon and pancreatic subcutaneous tumors were imagedin vivoafter intravenous administration of 1 nmol (150 mu g) CH88.2-800CW with the clinical Artemis NIRF imaging system using the Pearl Trilogy small animal imager as reference. One week post-injection of the tracer, tumors and organs were resected and tracer uptake was analyzedex vivo. Results IHC analysis showed strong FG88.2 staining on colonic, gastric, and pancreatic tumors, while staining on their normal tissue counterparts was limited. Next, human cancer cell lines HT-29 (colon) and BxPC-3 and PANC-1 (both pancreatic) were identified as respectively high, moderate, and low Lewis(a/c/x)-expressing. Using the clinical NIRF camera system for tumor-bearing mice, a mean tumor-to-background ratio (TBR) of 2.2 +/- 0.3 (Pearl: 3.1 +/- 0.8) was observed in the HT-29 tumors and a TBR of 1.8 +/- 0.3 (Pearl: 1.9 +/- 0.5) was achieved in the moderate expression BxPC-3 model. In both models, tumors could be adequately localized and delineated by NIRF for up to 1 week.Ex vivoanalysis confirmed full tumor penetration of the tracer and low fluorescence signals in other organs. Conclusions Using a novel chimeric Lewis(a/c/x)-targeting tracer in combination with a clinical NIRF imager, we demonstrate the potential of targeting Lewis glycans for fluorescence-guided surgery of gastrointestinal tumors. Show less
Biopharmaceuticals are among the most celebrated drugs. However, despite decades of experience, our understanding of many in vivo pharmacokinetic and adverse effects of biopharmaceuticals is... Show moreBiopharmaceuticals are among the most celebrated drugs. However, despite decades of experience, our understanding of many in vivo pharmacokinetic and adverse effects of biopharmaceuticals is still limited. These include the delay in reaching the maximum plasma concentration for an intravenously administered therapeutical protein, and the highly variable plasma concentration during elimination of monoclonal antibodies. Both observations can be explained by dynamical binding (‘stickiness’) of proteins to various (bodily) surfaces. Biopharmaceuticals also frequently contain (non-human) impurities, some of which are harmful when administered (‘dirtiness’). This toxicity often is the result of an intricate interplay of multiple cell types and effector pathways which can be difficult to simulate in the laboratory. More sophisticated test platforms are available, which can detect a number of untoward reactions that would previously not have been discovered. However, no laboratory test is fail-safe, and awareness of the possibility of adverse immunostimulation caused by biopharmaceuticals is the most important aspect for early detection and prevention of such cases in the future. Show less
Inman, R.D.; Baraliakos, X.; Hermann, K.G.A.; Braun, J.; Deodhar, A.; Heijde, D. van der; ... ; Hsu, B. 2016
Antibody drug conjugates (ADCs) are emerging as powerful anti-cancer treatments. They are designed to combine the tumor specificity, pharmacokinetics and biodistribution properties of antibodies... Show moreAntibody drug conjugates (ADCs) are emerging as powerful anti-cancer treatments. They are designed to combine the tumor specificity, pharmacokinetics and biodistribution properties of antibodies with the potent cell-killing activity of small molecules. The approval of brentuximab vedotin (Adcetris) for the treatment of Hodgkin lymphoma and trastuzumab emtansine (Kadcyla) for the treatment of metastatic breast cancer has spurred clinical development of ADCs. As the field of ADCs is rapidly emerging, a better understanding of the requirements needed for optimal intracellular delivery of ADCs seems mandatory. The aim of this thesis was to better understand the antibody and antigen requirements that are needed for effective ADC treatment. Different tumor antigens and targeting antibodies were compared for their capacity to deliver a cytotoxic payload to tumor cells, uncovering general mechanisms. In the course of this work, TF was identified as an excellent ADC target because of its rapid internalization and lysosomal targeting characteristics. Furthermore we have explored a novel Ab platform that improves the intracellular delivery of cytotoxic payloads. These findings provide a better insight in the Ab and antigen requirements needed for optimal payload delivery and support the development of novel and further improved ADCs for the treatment of cancer. Show less
Melief, C.J.M.; Scheper, R.J.; Vries, I.J.M. de 2014
What is known about celiac disease? Celiac disease is one of the most common food intolerances, approximately 1% of the population being a celiac disease patient. It is now known that celiac... Show moreWhat is known about celiac disease? Celiac disease is one of the most common food intolerances, approximately 1% of the population being a celiac disease patient. It is now known that celiac disease is precipitated by ingestion of gluten, the major storage proteins in wheat, and similar proteins in related cereals like barley, rye and triticale (hybrid between wheat and rye). The most common complains of patients consuming gluten are abdominal pain, diarrhea and vomiting. Also neurological symptoms, infertility and retardation of growth can occur. For a positive diagnosis of celiac disease a histological examination of a small bowel biopsy and a clinical improvement upon the introduction of a gluten-free diet is required. None invasive, serological assays are available that measure the presence and titer of IgA antibodies specific for gliadin, deamidated gliadin, endomysium and tissue transglutaminase. Almost without exception celiac disease develops only in genetically predisposed individuals: over 98% of the patients express either HLA-DQ2 or HLA-DQ8. Next to the genetic component also other factors especially environmental play a role in disease development. Celiac disease is an immune mediated disease, in which gluten peptides come in contact at the level of the small intestine with gluten specific T cells. These T cells could only be isolated from the small intestine of patients and not of healthy controls. Specific gluten sequences rich in prolamine and glutamine amino acids, resist degradation in the gastro-intestinal tract and after deamidation by the enzyme tTg are recognized by T cells. As a result of the inflammation, the mucosa loses its villi and strongly diminishes the absorption surface causing specific symptoms associated with the disease. The current treatment for celiac disease is strict adherence to a life-long glutenfree diet. The wide-spread use of gluten and gluten-derived starch in the food industry makes the gluten-free diet challenging. It is not surprising that a considerable proportion of patients, especially adolescents, are interested in alternative treatments that would allow gluten consumption. Thesis content My project, which makes the content of this book, has focused on the development of alternatives to the gluten-free diet. Two different approaches were investigated: the use of enzymatic supplementation and the identification and/or development of a less/non-toxic cereal. Chapter 1 is a general introduction to celiac disease. In chapter 2 the characterization of monoclonal antibodies raised against T cell stimulatory gluten peptides is described. Their reactivity against the prolamins from wheat, barley, rye and oats was determined and compared with that of gluten reactive T cells. The results demonstrate that the antibody and T cell reactivity patterns overlap significantly, indicating that the antibodies can be used to detect toxic sequences in Summary 122 gluten. Subsequently, these antibodies were used in the studies aimed at the development of alternative to the gluten-free diet. In chapter 3 we propose a new strategy to generate non-toxic gluten. Our experiments demonstrated that non-immunogenic epitope variants were present in certain diploid wheat varieties that differ one amino acid with the toxic variant. Moreover, we found that by the introduction of this naturally occurring amino acid substitution in other toxic epitopes their T cell stimulatory activity was likewise eliminated. This approach can thus be used to generate gluten genes that are devoid of any T cell stimulatory activity and presumably safe for consumption by celiac disease patients. In chapter 4 we investigate the safety of oats for consumption by celiac disease patients. We confirmed that commercially available oats are without exception contaminated with other cereals. Perhaps more importantly, we demonstrate that variability exists in the level of T cell stimulatory gluten like peptides in a panel of oats varieties tested, opening the way to select and/or breed oats varieties that contain no harmful gluten-like proteins. In chapter 5 we investigate the potential of AN-PEP, a prolyl-endoprotease produced by the microorganism Aspergillus niger, to degrade gluten in an artificial gastrointestinal tract system. The enzyme proved very efficient in degrading all toxic epitopes in this system, even when a complex meal was introduced. These __in vitro__ studies now justify a clinical trial to assess the safety and effectiveness of the enzyme for gluten degradation in patients. In chapter 6 I discuss how the results may lead to novel treatment modalities and novel foods in the near future. Show less
Control of allo- and auto-immunity is important for pancreas and islet transplantations. In chapter 2 different mechanism of actions of humanized monoclonal antibodies against CD3 and CD25 versus... Show moreControl of allo- and auto-immunity is important for pancreas and islet transplantations. In chapter 2 different mechanism of actions of humanized monoclonal antibodies against CD3 and CD25 versus ATG are described. ATG leads to depletion of auto-reactive T-cells by ADCC, CDC and apoptosis induction, while anti-CD3 and daclizumab inhibited T-cell autoreactivity in a non-depleting fashion. In chapter 3, our experience with induction therapy with ATG and daclizumab was reported. ATG Fresenius or daclizumab were well tolerated and equally effective in reducing the incidence of acute rejections in simultaneous pancreas kidney transplantation. Data in Chapter 4 imply that daclizumab is more specifically affecting diabetes related immune responses compared to ATG. Islet transplantation provides an attractive and less invasive alternative to whole-organ pancreas transplantation. In chapter 5 we demonstrated the ability of our T-cell monitoring methods to determine the fate of repeated islet allografts transplanted into patients that express repeated mismatches. In most pancreas transplantations the enteric drainage is favoured exocrine duct management. Facing a higher risk on anastomotic complications in enteric drained pancreas transplantations, primary bladder drainage may be the preferred option. In Chapter 6, we demonstrated that primary bladder drainage followed by enteric conversion is a safe and effective procedure. Show less
