Danish Multiple Sclerosis center Annual report 2010

Transcription

1 DepArtMeNt of Neurology the NeuroScIeNce centre copenhagen university HoSpItAl rigshospitalet copenhagen, DeNMArk Danish Multiple Sclerosis center Annual report 2010 DANISH MultIple ScleroSIS center ANNuAl report

2 DMSC staff seminar DANISH MultIple ScleroSIS center ANNuAl report 2010

3 Table of contents Annual Report A short review of 2010 in the Danish Multiple Sclerosis Center Missions and aims About the Danish Multiple Sclerosis Center Organization diagram Research activities 2010 Clinical research Neuroimaging Neurogenetics Neuroimmunology Neuropathology Routine analyses in Neuroimmunology Laboratory Scientific publications Peer reviewed original papers 2009 Peer reviewed original papers 2010 Prizes Honorary offices Scientific collaboration National International Pharmaceutical companies on clinical trials Acknowledgements DANISH Multiple sclerosis CENTER annual report

4 Publisher: Danish Multiple Sclerosis Center Authors: Per Soelberg Sørensen Morten Blinkenberg Finn Sellebjerg Annette Oturai Helle Bach Søndergaard Poul Erik H. Jensen Photos: Morten Blinkenberg Concept, design, graphic production and print: Stibo Zone Njalsgade 19 D DK-2300 København S Tlf.: DANISH Multiple sclerosis CENTER annual report 2010

5 Professor Per Soelberg Sørensen, MD, DMSc Director of the Danish Multiple Sclerosis Center (DMSC) A short review of 2010 in the Danish Multiple Sclerosis Center 2010 was the year when we expected to be able to offer our patients the first tablet to treat multiple sclerosis. However, one of the expected drugs, Cladribine, received a negative opinion of the European Medicines Agency (EMA) and the decision on the other tablet, Gilenya, was delayed. Late in 2010 Gilenya achieved a positive opinion by EMA but only for treatment of patients who did not respond satisfactorily to the injectible drugs, interferon-beta and glatiramer acetate. Gilenya will be marketed from May The activity in Danish Multiple Sclerosis Center (DMSC) has continued to increase in 2010 despite the fact that DMSC had the same number of MS specialist nurses and a reduced staff of MS neurologist compared with This has only been possible due to the extra-ordinary efforts by all members of the DMSC staff. The number of patients receiving highly specialized therapy has increased and by the end of 2010 more than 350 patients were receiving monthly infusions of Tysabri, meaning that more than 20 patients attend the outpatient clinic every day for intravenous infusion of disease modifying drugs. It has been a logistic challenge to accommodate patients wishes for infusions on particular days. Fortunately we have had the opportunity to equip a second infusion room in In 2010 we completed a multi-center, international trial organized and directed from DMSC using add-on treatment of Simvastatin to interferon-beta. Unfortunately we did not see any beneficial effects of this combination. We have continued our efforts to find effective therapy for patients with progressive forms of MS and have initiated 2 new clinical trials in patients with progressive MS investigating Tysabri and monthly pulses of methylprednisolone. We have continued our search for biomarkers that can tell if a patient respond to a certain therapy, and in pathological studies we have described differences between primary progressive and secondary progressive MS in inflammation and demyelination in the brain. We have described the pathological processes responsible for the steady worsening of symptoms in patients with progressive forms of MS and found the explanation why symptoms often seem to recur with the same localization. I hope you will enjoy reading the annual report of DMSC. Per Soelberg Sørensen DANISH Multiple sclerosis CENTER annual report

6 DMSC missions and aims The mission of Rigs hospitalet is to be the leading hospital in Denmark for patients in need of highly specialized treatment The missions of the Danish Multiple Sclerosis Center (DMSC) are: The aims of the DMSC are: to be the leading multiple sclerosis (MS) center in Denmark to be at the forefront of highly specialized management of MS to carry out research and development in MS at an advanced international level to collaborate scientifically and exchange knowledge in MS research to educate staff to a highly specialized level in their relevant fields to contribute with professional advice on MS to the healthcare community to meet people with MS at their terms with openness and respect to provide the optimal interdisciplinary patient care to all MS patients in the region and to patients from other regions in need of highly specialized therapy to carryout high quality research in MS with focus on clinical research, new therapies, MS genetics, neuroimmunology and MS pathology to teach undergraduate students and PhDstudents and stimulate their interest in MS research to educate post docs, MS physicians, nurses, secretaries and other professionals to a high level of knowledge of MS in their relevant expert fields to lead the national research in Denmark in partnership with other Danish researchers and to establish a broad international collaboration with MS research groups in Europe and from overseas. 6 DANISH Multiple sclerosis CENTER annual report 2010

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8 About The Danish Multiple Sclerosis Center 8 DANISH Multiple sclerosis CENTER annual report 2010

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10 The Danish Multiple Sclerosis Center About The Danish Multiple Sclerosis Center The Danish Multiple Sclerosis Center (DMSC) is offering highly specialized therapy and is the leading center for MS research in Denmark. Together with Danish colleagues we are responsible for the vast majority of clinical and translational MS research in Denmark, and we collaborate with MS researchers from all over the world. DMSC is composed of a multidisciplinary MS clinic and a research unit. The MS Clinic is located on the 8th floor of the main complex of Rigshospitalet and comprises the offices of the professor and consultants, the nurses offices, the reception desk and the secretary offices as well as the outpatient consultation rooms and facilities for intravenous therapy with disease modifying drugs and rooms for invasive procedures. DMSC provides multidisciplinary care for more than 1900 MS patients, and offers both basic and highly specialized therapy. The National Board of Health has appointed DMSC to perform highly specialized therapy such as Tysabri, strong immunosuppression and experimental therapies. DMSC is a center for children and adolescence with MS in Eastern Denmark and has a highly specialized function in treating neuromyelitis optica, once thought to be a variant of MS, but now considered to be a separate disease entity. DMSC also offers treatment of severe spasticity with an intrathecal baclofen pump, not only to patients with MS but also to other patients with diseases or traumatic injuries causing severe spasticity. It is the aim of the MS Clinic to provide high quality multi-disciplinary care for all our patients with openness and respect. Our staff comprises a professor, 5 consultants, 2 staff neurologists and several external consultants working part time in the MS Clinic. There is one leading nurse and 7 MS specialist nurses, 3 secretaries, a neuropsychologist, a physiotherapist and a medical social counselor. We serve patients from the Copenhagen capital region and many patients from neighbouring regions and from all over Zealand are referred for highly specialized therapy. The MS Research Unit is partly located in the proximity of the MS Clinic, where most patients related to clinical research takes place and where the offices of 3 research nurses and 1 research secretary are embedded. The remaining part of the MS Research Unit is located on the first floor in the Michaelsen Building 63 and in the basement of building 93. These facilities contain the Neuroimmunology Laboratory and offices for the research staff. The laboratory is equipped with an 8-color flow cytometer and facilities for doing real-time polymerase chain reaction (PCR). Further, the facilities contain the MS Biobank and the neurogenetics laboratory for DNA preparation and facilities for making routine tests. The focus of the research in DMSC is clinical research including neuroimaging, neuroimmunology, neurogenetics and neuropathology of MS. ACtive patients in DMSC DANISH Multiple sclerosis CENTER annual report 2010

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12 Organization Director: Professor Per Soelberg Sørensen MS clinic MS Research Unit Neurologists Professor Per Soelberg Sørensen Consultant Morten Blinkenberg Consultant Finn Sellebjerg Consultant Annette Oturai Consultant Karen Schreiber Consultant Ana Voldsgaard Staff neurologist Melinda Magyari Staff neurologist Henrik Mathiesen PhD student Stephan Bramow PhD student Lars Börnsen PhD student Jeppe Romme Christensen PhD student Rikke Ratzer Junior physician Morten Møller MS nurses Leading nurse Anne Hansen Dorte Stauning Rasmussen Anette Husted Pedersen Lene Almind Julie Yoon S. Moberg Louise Nathalie Christiansen Maj Daae Christensen Sidsel Nielsen Secretaries Annette Larsen Malene Møllesøe Helle Vilhelmsen Neuropsychologist Agnete Jønsson Physiotherapist Lis Albrechtsen Medical social counselor Keld Nissen Clinical research Professor Per Soelberg Sørensen Consultant Karen Schreiber Staff neurologist Ana Voldsgaard Staff neurologist Melinda Magyari Neuropsycologist Agnete Jønsson Research nurses Vibeke Jespersen Joan Pietraszek Sidsel Nielsen Research secretary Annette Larsen Neuroimaging research Consultant Morten Blinkenberg Staff neurologist Henrik Mathiesen Genetic research Consultant Annette Oturai Senior research fellow Helle Bach Søndergaard Neuroimmunology research Ass. professor Finn Sellebjerg Senior research fellow Helle Bach Søndergaard PhD students Lars Börnsen Jeppe Romme Christensen Rikke Ratzer Julie Maria Hejgaard Dan Hesse Junior research fellow Marianne Hansen Neuropathology research Professor Per Soelberg Sørensen Ph.d. student Stephan Bramow Neuroimmunology Laboratory Laborarory leader Poul Erik Hyldgaard Jensen Laboratory technicians Leading Laboratory technician Joy Mendel-Hartvig Marie Koefoed Anne Mette Hedegaard Nielsen Michael Jensen Vibeke Fuglholt 12 DANISH Multiple sclerosis CENTER annual report 2010

13 Professor Per Soelberg Sørensen Ass. professor Finn Sellebjerg Consultant Morten Blinkenberg Consultant Annette Oturai Consultant Karen Schreiber Consultant Ana Voldsgaard Staff neurologist Henrik Mathiesen Staff neurologist Melinda Magyari Laboratory leader Poul Erik Hyldgaard Jensen Senior research fellow Helle Bach Søndergaard Leading laboratory technician Joy Mendel- Hartvig Leading nurse Anne Hansen DANISH Multiple sclerosis CENTER annual report

14 Research activities 2010 Clinical research Clinical research Neuroimaging Neurogenetics Neuroimmunology Neuropathology Routine analyses in Neuroimmunology Laboratory 14 DANISH Multiple sclerosis CENTER annual report 2010

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16 Research activities 2010 Clinical research Clinical research group: Per Soelberg Sørensen, Morten Blinkenberg, Finn Sellebjerg, Annette Oturai, Ana Voldsgaard, Karen Schreiber, Henrik Mathiesen, Melinda Magyari, Lars Börnsen, Jeppe Romme Christensen, Rikke Ratzer, Julie Maria Hejgaard, Agnete Jønsson, Vibeke Jespersen, Joan Pietraszek, Sidsel Walther Nielsen, Anne Hansen, Annette Larsen. Therapeutic trials In 2010 we completed the SIMCOMBIN study, which is a Nordic multi-center study directed from DMSC and conducted in 42 MS Centers in Denmark, Norway, Sweden and Finland. The study investigated simvastatin as add-on therapy to interferon-beta in de novo treated patients with relapsing-remitting MS. More than 300 patients participated in the trial. Unfortunately the results showed that there was no benefit of add-on of simvastatin to interferon-beta. We have recently conducted another combination trial, which is a multi-center European trial exploring the effect of Minocycline as add-on therapy to interferon-beta in de novo treated patients. The trial was completed in April 2011, and the results will be available in the summer of We are currently performing several single-center studies in patients with progressive MS in order to try to find treatment options for this phase of the disease that currently lags effective therapy. In this regard we study the effect of erythropoietin (EPO) on disability in patients with progressive MS and the aim is to include 56 patients and to finalize inclusion in We have performed a small safety study with eggs of the pig whipworm (Trichuris suis). This small trial has been completed, and the data are currently under examination. If the result is positive we will embark a phase II trial with inclusion of 80 patients. In patients with progressive MS, we are testing the effect of erythropoietin (EPO) on permanent MS symptoms, and we are conducting an exploratory trial of natalizumab (Tysabri) in patients with 16 DANISH Multiple sclerosis CENTER annual report 2010

17 progressive MS and are planning a similar trial investigating the effect of monthly cycles of methylprednisolone tablets. Other clinical research trials In 2010 we initiated a study exploring the role of vitamin D on clinical disease activity in MS. Vitamin D seems to yield some protection against encountering MS and may also influence the disease activity in established MS. MS is increasing particularly in women. Whereas the incidence of MS has been almost unchanged in men, it has doubled in women since In collaboration with the Danish MS Register we embarked on an extensive analysis of possible factors that might have contributed to the increase of MS in women. We will explore demographic factors, such as changes in working conditions, merital status, childbirth, smoking habits and vitamin D intake. DMSC is among the leading centers in the world regarding studies of antibodies against biological agents. We have extensively studied the effect of neutralizing antibodies against interferon-beta, most recently in a EU supported European study of neutralizing antibodies against interferon-beta (NABINMS study). We have introduced a new assay for detecting neutralizing antibodies based on a luciferase reporter gene under control of interferon-beta. Recently we have implemented an analysis of antibodies against natalizumab (Tysabri) and have conducted and international study of the frequency of occurrence of antibodies against natalizumab together with MS centers in Sweden, Norway and Germany. We were able to show that fewer patients developed persistent antibodies against natalizumab compared with the observation in clinical studies. We have also shown that the propensity to develop antibodies against interferon-beta does not carry an excess risk of developing antibodies against natalizumab. We are currently doing a study of interferonalpha in patients who have developed neutralizing antibodies against interferon-beta to see whether these patients have maintained a full biological response to interferon-alpha and therefore might be treated with interferon-alpha. DANISH Multiple sclerosis CENTER annual report

18 Research activities 2010 Neuroimaging Neuroimaging research group: Morten Blinkenberg, Henrik Mathiesen, Per Soelberg Sørensen PET During the last decades, functional imaging have improved our understanding of the neurodegenerative processes in MS. Former positron emission tomography (PET) studies, carried out in Danish Multiple Sclerosis Center (DMSC), have shown that cerebral activation in MS patients, is severely reduced as a consequence of disease progression. A PET study focusing on the early relapsing remitting phase of the disease and the corresponding changes in cerebral activation has recently been performed in DMSC. The study shows, that reductions in PET are associated with reduced magnetic resonance spectroscopy (MRS) measures of N-acetyl-aspartate (NAA) normalized to Creatine (NAA/Cr), reflecting neuronal dysfunction or loss in MS. In this way there seem to be a relationship between these two different measures of cerebral neuronal integrity in MS, which have implication for the further use of MRS in MS. MRI In collaboration with Danish Research Centre for Magnetic Resonance, we have previously shown, that MRS measurements of NAA/Cr correlate with cognitive dysfunction in MS. This cohort has now been re-evaluated and analyzed for longitudinal changes in MRS. Preliminary data show, that MRS decrease in the early stage of MS, predicts disease progression after 5 years. MRS may therefore be used as a clinical marker, to determine disease course in MS. Another study focuses on the pathophysiological mechanisms underlying changes in cerebral activation in MS patients. Resting-state fmri is a new approach to assess functional brain connectivity by measuring the synchronous fluctuation in the blood-oxygenlevel dependent signal between remote brain regions at rest. PhD-student, Anne-Marie Dogonowski, uses this method to study, whether changes in functional connectivity of the motor network, reflect disease severity in patients with MS. Preliminary results show, increased coupling between premotor cortex and the motor network, which might reflect an adaptive mechanism to maintain motor function with increasing clinical disability. These data highlight the potential of resting-state fmri to study disease-related functional reorganization of distinct brain networks in multiple sclerosis and encourage further research in this field. 18 DANISH Multiple sclerosis CENTER annual report 2010

19 Neurogenetics Neurogenetics research group: Annette Bang Oturai, Helle Bach Søndergaard, Finn Sellebjerg, Julie Maria Hejgaard The ultimate cause of multiple sclerosis (MS) is still unknown. Probably a combination of hereditary and environmental factors trigger a defect in the immune system that will lead to MS. The frequency of MS varies geographically and between ethnic groups, with the greatest risk in white northern Europeans living in temperate regions. From family studies we have known for many years that genes plays a role, and that MS susceptibility is influenced by genetic variations within the major histocompatibility complex (MHC). We have previously performed linkage studies investigating Danish and Nordic sib pair families, and later participated in the ultimate MS linkage study investigating >700 European MS families revealing MHC as the only genome-wide linkage signal in MS with a lod score of 11,7, dominated by the DR2 (DRB1*15:01-DQB1*06:02) haplotype. We have collected DNA for more than 15 years, and today we have DNA from more than 1,800 Danish MS patients and 1,200 controls, all kept in the»danish Multiple Sclerosis Biobank«in our department at Rigshospitalet. In order to increase the sample size for genetic testing, we have participated in the»nordic MS Genetic Network«since 1994, and today the Nordic material consists of more than 6,000 MS cases and 6,000 controls. Local research is focused on the candidate gene approaches and the genetic influence on the differences in treatment response. We are part of the IMSGC (International Multiple Sclerosis Genetic Consortium) and the Wellcome Trust Case Control Consortium (WTCCC), where 23 research groups from 15 countries are performing the largest set of MS genome-wide association study (GWAS), genotyping 11,000 cases and 11,000 controls using 500,000 SNP chip. Primary results have elucidated associations to more than 100 gene variations (SNPs). Following this collaboration we are joining the Immunochip Consortium, where 1,000 Danish cases and 1,000 Danish controls participate in a large scale genetic analysis, investigating best genes/regions/snps in MS as well as 9 other autoimmune diseases, together with other international MS groups, looking for shared autoimmune genes. The risk of MS has been increasing over the last 50 years, especially among women older than 40. On this background we have initiated a PhD project looking at aspects of gender differences, including different treatment responses. Furthermore, we have initiated a large-scale vitamin D PhD project, investigating gene variations within the vitamin D pathway, and the importance of vitamin D in clinical and immunological disease activity. In addition, we have collected more than 800 questionnaires from MS patients dealing in detail with lifestyle and environmental exposure, giving the possibility to study gene-environmental interaction. DANISH Multiple sclerosis CENTER annual report

20 Research activities 2010 Neuroimmunology Neuroimmunology research group: Finn Sellebjerg, Helle Bach Søndergaard, Poul Erik Hyldgaard Jensen, Jeppe Romme Christensen, Lars Börnsen, Rikke Ratzer, Per Soelberg Sørensen Immunological studies It is becoming increasingly clear that relapsing-remitting MS is caused by repeated attacks of inflammatory demyelination and axonal damage. These attacks are initiated by inflammatory cells that are activated within the immune systems, recirculate in blood, and access the brain and spinal cord by crossing the different blood-brain barrier systems. Based on animal experiments, MS has been thought to be mainly a T cell-driven disease. Clinical trials do, however, show that in addition to treatment with natalizumab, that blocks the migration of all mononuclear cells into the CNS, B cell depletion is also efficacioius in relapsing-remitting MS. More recent studies have suggested that even in progressive MS, which has been thought to be caused mainly by neurodegenerative processes, inflammation may be crucial in the pathogenesis. We study the mechanism of immune activation in MS, addressing the reactivity of subsets of T cells and B cells to autoantigens expressed in the brain and spinal cord, and address how these and other leukocytes contribute to the activation of T cells. We also study the effect of immunomodulatory treatment on these processes, and focus specifically on the mechanism of action of interferon-beta since recent studies from our laboratory have suggested that endogenous production of this cytokine may have a protective role in MS. In other studies we use flow cytometry to study the phenotype of individual, circulating lymphocytes by measuring the binding of fluorochrome-coupled, monoclonal antibodies to distinct molecules. By combining the analysis of different molecules expressed on the cell surface, these cells can be divided into a large number of functionally relevant subtypes, which can be quantitated both in relative and absolute terms. We are currently studying an array of activation and differentiation markers on T cell subsets, B cells, NK cells, monocytes and dendritic cells to explore the activation status of these cell types in patients with relapsingremitting, primary and secondary progressive MS. These studies will provide novel insights into immune activation in subtypes of MS. Molecular biology Activation of immune responses depends on interactions between different immune cells and coordinated, tightly regulated expression of a vast number of molecules within single cells. Gene expression is controlled by the activity of transcription factors that are either constitutively expressed in active forms, expressed in forms that require activation by other signals, or are inducible on cellular activation. The transcription factors direct the expression of messenger RNA (mrna) from the genes encoded by the DNA sequence, and after export from the nucleus the mrna provides a template for protein synthesis on ribosomes in the cytosol. Within the last decade it has become apparent that endogenous, small RNA molecules termed microrna (mirna) have a key role in regulating the translation of protein from mrna in the cytosol. MiRNA can either induce the degradation of mrna, or can inhibit the translation of mrna into protein by binding to the 3 untranslated region of mrna molecules. Furthermore, the accessibility of a genomic region can be regulated by epigenetic modifications of the DNA strand. Recent studies have identified mirna molecules that are differentially expressed in MS patients and healthy controls, and it has been suggested that pathogenic immune activation in MS may, indeed, reflect changes in mirna expression. We have studied mirna expression in MS, and have found that even patients with MS in clinical remission show clear changes in the expression of mirna compared to healthy control subjects. Furthermore, we have identified mirna molecules that are specifically regulated by treatment with interferon-beta. We are now studying the extent to which mirna expression changes in pregnant women with MS, as pregnancy is known to dampen disease activity in relapsing-remitting MS. These studies are complemented by mrna expression studies in subtypes of mononuclear cells, isolated by immunomagnetic technology, from patients 20 DANISH Multiple sclerosis CENTER annual report 2010

21 with relapsing-remitting, primary and secondary progressive MS. Taken together our studies provide novel insights into the molecular mechanisms of the pathogenic immune responses in MS. As mirna can now be therapeutically introduced into specific human cells, the identification of mirnas that can modulate pathogenic immune responses have a strong potential for the treatment of MS in the future. Biomarker studies The term biomarker is used for gene products or proteins that can be measured in blood or other body fluids, and reflects a pathogenetically or therapeutically relevant in vivo process. Immunological and molecular biology studies provide the platform for the development of biomarkers, but the validation of these also requires access to collections of well characterized samples from MS patients, who are followed prospectively. Such biomarker studies can provide insights into the pathogenesis of MS and our understanding of the therapeutic effects of immunomodulatory and immunosuppressive treatments. The development of biomarkers that can serve as surrogate outcomes in clinical trials is an important aim of the ongoing biomarker research at our center. We have studied the immunological effects of treatment with natalizumab, interferon-beta and glatiramer acetate. The studies have resulted in the validation of biomarkers that may reflect the therapeutic effect of treatment better than the currently used biomarkers, and are now being studied in clinical trials of patients with primary and secondary progressive MS. We continue to study the mechanisms and effects of antibodies to biopharmaceutical therapies interferon-beta and natalizumab in MS. Most recently we have shown that although antibody responses to glatiramer acetate develop during therapy, they do not appear to influence the response to therapy. Finally, we have identified immune activation markers that are upregulated in a subgroup of patients treated with interferon-beta. This response is associated with increased disease activity during interferon-therapy. We are now exploring how this response is induced and how it may increase the pathogenic processes in MS. With the introduction of a number of new MS therapeutics in the coming years, a better understanding of the different therapies is urgently needed. Indeed, some patients may do well on a safe first-line therapy with moderate efficacy, others require more efficacious therapies which are usually associated with an increased risk of severe side effects. We will continue to study how genetic markers and other biomarkers can be used to tailor individual MS therapy. DANISH Multiple sclerosis CENTER annual report

22 Research activities 2010 Neuropathology Neuropathology research group: Per Soelberg Sørensen, Stephan Bramow, (Henning Laursen, Laboratory of Neuropathology) In 2010 we published a scientific work showing that whereas demyelination was less profound in brains of primary progressive patients compared to secondary progressive patients, demyelination in the spinal cord was similar. We also demonstrated that remyelinated areas had increased vulnerability and recurrent demyelination in the remyelinated areas were more frequent than appearance of new demyelinating plaques. This could explain why patients often develop recurrence of symptoms in new relapses. We also showed that diffuse new inflammation correlated with active focal demyelination emphasizing the necessity of an action on both sides of the blood-brain-barrier for new treatments of progressive MS. 22 DANISH Multiple sclerosis CENTER annual report 2010

23 Routine analyses in Neuroimmunology Laboratory Neuroimmunology Laboratory research group: Poul Erik H. Jensen, laboratory technicians: Joy Mendel-Hartvig, Michael Kolbjørn Jensen, Vibeke Fuglholt, Rikke Larsen. Diagnostic evaluation The presence in CSF of oligoclonal IgG-bands is of interest in the diagnosis of Multiple Sclerosis (MS). In 2010 we have analyzed 813 patient samples, using isoelectric focusing of CSF and corresponding plasma samples for the characterization of IgG bands. In the autoimmune disease Myasthenia gravis (MG), autoantibodies against the acetylcholine receptor (AChR) may cause a diminished binding of ACh on muscular surfaces and thereby a reduced impulse transmission to the postsynaptic membrane of the neuromuscular endplate occurs. For diagnostic and therapeutic purposes, we measure the concentrations of these autoantibodies from patient serum samples, using a radioimmunoassay kit, and in 2010 we analyzed 1324 patient samples. Measurement of neutralizing antibodies Subgroups of MS patients, treated with Interferonbeta or Tysabri, generate neutralizing antibodies, which diminish the therapeutic effects. Interferonbeta molecules bind to leucocytes and a specific up-regulation of MxA mrna in the cells occur. Neutralizing antibodies may abolish this effect, and therefore we measure the neutralization of Interferon-beta by antibodies in new cell-culture assay based on luciferase-induced expression, and further by the MxA mrna-expression as a biological response to treatment with Interferon-beta. In 2010 we have analyzed 1029 patient samples for neutralizing antibodies, and 151 patient samples for MxA mrna expression. Furthermore, we have screened 165 patient samples for Interferon-beta binding antibodies using an ELISA-assay. The action of Tysabri differs from Interferonbeta, since it blocks mononuclear cell binding to endothelial cells (alpha-4 integrin antagonist). In this way Tysabri inhibits mononuclear cells from entering the central nervous system. The generation of neutralizing antibodies to Tysabri in MS patients blocks the biological effects of Tysabri. In 2010 we analyzed 572 blood samples for the presence of antibodies to Tysabri by ELISA. DANISH Multiple sclerosis CENTER annual report