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ABSTRACT: Transcriptomic and proteomic analyses of multiple sclerosis (MS) lesions indicate alterations in the gamma-aminobutyric acid (GABA) inhibitory system, suggesting its involvement in the disease process. To further elucidate the role of GABA in central nervous system (CNS) inflammation in vivo, the chronic myelin oligodendrocyte glycoprotein (MOG)(35-55) experimental autoimmune encephalomyelitis (EAE) model was used. Daily GABA injections (200mg/kg) from day 3 onwards significantly augmented disease severity, which was associated with increased CNS mRNA expression levels of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6. GABA-treated mice showed enhanced MOG-dependent proliferation and were skewed towards a T helper 1 phenotype. Moreover, in vitro, the lipopolysaccharide (LPS)-induced increase in interleukin (IL)-6 production by macrophages was enhanced at low GABA concentrations (0.03-0.3mM). In sharp contrast to exogenous GABA administration, endogenous GABA increment by systemic treatment with the GABA-transaminase inhibitor vigabatrin (250mg/kg) had prophylactic as well as therapeutic potential in EAE. Together, these results indicate an immune amplifying role of GABA in neuroinflammatory diseases like MS.
Journal of neuroimmunology 11/2012; · 2.84 Impact Factor
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ABSTRACT: Aging of the immune system contributes to the increased morbidity and mortality of the elderly population and may occur prematurely in patients with immune disorders. One of the main characteristics of immunosenescence is the expansion of CD4(+)CD28(-) T cells in the blood. These cells are effector memory T cells with cytotoxic capacity, and have been recently described to have pathogenic potential in a variety of immune disorders. Interestingly, CD4(+)CD28(-) T cells have now been found to infiltrate target tissues of patients with multiple sclerosis, rheumatoid arthritis, myopathies, acute coronary syndromes, and other immune-related diseases. In this review, we discuss potential factors and mechanisms that may induce the expansion of these cells, as well as their putative pathogenic mechanisms in immune disorders.
Trends in Molecular Medicine 07/2012; 18(8):446-53. · 10.35 Impact Factor
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Jeroen F J Bogie,
Silke Timmermans,
Vân Anh Huynh-Thu,
Alexandre Irrthum,
Hubert J M Smeets,
Jan-Åke Gustafsson,
Knut R Steffensen,
Monique Mulder, Piet Stinissen,
Niels Hellings,
Jerome J A Hendriks
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ABSTRACT: Multiple sclerosis is a chronic, inflammatory, demyelinating disease of the central nervous system in which macrophages and microglia play a central role. Foamy macrophages and microglia, containing degenerated myelin, are abundantly found in active multiple sclerosis lesions. Recent studies have described an altered macrophage phenotype after myelin internalization. However, it is unclear by which mechanisms myelin affects the phenotype of macrophages and how this phenotype can influence lesion progression. Here we demonstrate, by using genome wide gene expression analysis, that myelin-phagocytosing macrophages have an enhanced expression of genes involved in migration, phagocytosis and inflammation. Interestingly, myelin internalization also induced the expression of genes involved in liver-X-receptor signaling and cholesterol efflux. In vitro validation shows that myelin-phagocytosing macrophages indeed have an increased capacity to dispose intracellular cholesterol. In addition, myelin suppresses the secretion of the pro-inflammatory mediator IL-6 by macrophages, which was mediated by activation of liver-X-receptor β. Our data show that myelin modulates the phenotype of macrophages by nuclear receptor activation, which may subsequently affect lesion progression in demyelinating diseases such as multiple sclerosis.
PLoS ONE 01/2012; 7(9):e44998. · 4.09 Impact Factor
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Annelies Vanheel,
Ruth Daniels,
Stéphane Plaisance,
Kurt Baeten,
Jerome J A Hendriks,
Pierre Leprince,
Debora Dumont,
Johan Robben,
Bert Brône, Piet Stinissen,
Jean-Paul Noben,
Niels Hellings
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ABSTRACT: A more detailed insight into disease mechanisms of multiple sclerosis (MS) is crucial for the development of new and more effective therapies. MS is a chronic inflammatory autoimmune disease of the central nervous system. The aim of this study is to identify novel disease associated proteins involved in the development of inflammatory brain lesions, to help unravel underlying disease processes. Brainstem proteins were obtained from rats with MBP induced acute experimental autoimmune encephalomyelitis (EAE), a well characterized disease model of MS. Samples were collected at different time points: just before onset of symptoms, at the top of the disease and following recovery. To analyze changes in the brainstem proteome during the disease course, a quantitative proteomics study was performed using two-dimensional difference in-gel electrophoresis (2D-DIGE) followed by mass spectrometry. We identified 75 unique proteins in 92 spots with a significant abundance difference between the experimental groups. To find disease-related networks, these regulated proteins were mapped to existing biological networks by Ingenuity Pathway Analysis (IPA). The analysis revealed that 70% of these proteins have been described to take part in neurological disease. Furthermore, some focus networks were created by IPA. These networks suggest an integrated regulation of the identified proteins with the addition of some putative regulators. Post-synaptic density protein 95 (DLG4), a key player in neuronal signalling and calcium-activated potassium channel alpha 1 (KCNMA1), involved in neurotransmitter release, are 2 putative regulators connecting 64% of the identified proteins. Functional blocking of the KCNMA1 in macrophages was able to alter myelin phagocytosis, a disease mechanism highly involved in EAE and MS pathology. Quantitative analysis of differentially expressed brainstem proteins in an animal model of MS is a first step to identify disease-associated proteins and networks that warrant further research to study their actual contribution to disease pathology.
PLoS ONE 01/2012; 7(4):e35544. · 4.09 Impact Factor
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Bieke Broux,
Kim Pannemans,
Xin Zhang,
Silva Markovic-Plese,
Tom Broekmans,
Bert O Eijnde,
Bart Van Wijmeersch,
Veerle Somers,
Piet Geusens,
Susanne van der Pol,
Jack van Horssen, Piet Stinissen,
Niels Hellings
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ABSTRACT: Immunosenescence, or ageing of the immune system, contributes to the increased morbidity and mortality seen in the elderly population. Premature immunosenescence is shown to occur in a subgroup of patients with autoimmune diseases. One of the main characteristics of immunosenescence is the expansion of CD4(+)CD28(-) T cells in the blood. In this study, we investigate the potential contribution of these cells to disease processes in a subgroup of multiple sclerosis (MS) and rheumatoid arthritis (RA) patients. Characterization of CD4(+)CD28(-) T cells in patients and healthy controls reveals that they have an inflammation-seeking effector-memory T cell phenotype with cytotoxic properties, as they expel cytotoxic granules in response to a polyclonal stimulus or MS-related autoantigens. We identify CX(3)CR1, the fractalkine receptor, as a selective marker to discriminate CD4(+)CD28(-) T cells from their CD4(+)CD28(+) counterparts. CX(3)CR1 expression enables CD4(+)CD28(-) T cells to migrate towards a fractalkine gradient in vitro. In addition, we find increased levels of fractalkine in the cerebrospinal fluid and inflammatory lesions of MS patients. We demonstrate for the first time that CD4(+)CD28(-) T cells accumulate in MS lesions of a subgroup of patients. Moreover, we have indications that these cells are cytotoxic in the target tissue. Overall, our findings suggest that CD4(+)CD28(-) T cells migrate in response to a chemotactic gradient of fractalkine to sites of inflammation, where they contribute to the inflammatory processes in a subgroup of patients with MS and RA.
Journal of Autoimmunity 11/2011; 38(1):10-9. · 7.37 Impact Factor
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ABSTRACT: Phage display is a high-throughput technology used to identify ligands for a given target. A drawback of the approach is the absence of PTMs in phage-displayed peptides. The applicability of phage display could be broadened considerably by the implementation of PTMs in this system. The aim of this study was to investigate the possible application of citrullination, a PTM of an arginine into a citrulline amino acid, in filamentous (M13) and lytic (T7) phage display. After in vitro citrullination of T7 and M13 phages, citrullination was confirmed and the infectivity of both citrullinated and non-citrullinated phage was compared by titer determination. We demonstrated the successful in vitro citrullination of T7 and M13 phage-displayed peptides. This in vitro modification did not affect the viability or infectivity of the T7 virions, a necessary prerequisite for the implementation of this approach in T7 phage display. For M13 phage, however, the infecting phage titer decreased five-fold upon citrullination, limiting the use of this modification in M13 phage display. In conclusion, in vitro citrullination can be applied in T7 phage display giving rise to a high-throughput and sensitive approach to identify citrulline-containing ligands by the use of the strengths of phage display technology.
Proteomics 06/2011; 11(12):2550-4. · 4.43 Impact Factor
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Laura Deckx,
Doris van Abbema,
Katherine Nelissen,
Liesbeth Daniels, Piet Stinissen,
Paul Bulens,
Loes Linsen,
Jean-Luc Rummens,
Geert Robaeys,
Eric T de Jonge, [......],
Daan Walgraeve,
Luc Spaas,
Jolanda Verheezen,
Thessa Verniest,
Alexander Goegebuer,
Hans Wildiers,
Franchette van den Berkmortel,
Vivianne C Tjan-Heijnen,
Frank Buntinx,
Marjan van den Akker
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ABSTRACT: Cancer is mainly a disease of older patients. In older cancer patients, additional endpoints such as quality of survival and daily functioning might be considered equally relevant as overall or disease free survival. However, these factors have been understudied using prospective designs focussing on older cancer patients. Therefore, this study will focus on the impact of cancer, ageing, and their interaction on the long-term wellbeing of older cancer patients.
This study is an observational cohort study. We aim to recruit 720 cancer patients above 70 years with a new diagnosis of breast, prostate, lung or gastrointestinal cancer and two control groups: one control group of 720 patients above 70 years without a previous diagnosis of cancer and one control group of 720 cancer patients between 50 - 69 years newly diagnosed with breast, prostate, lung or gastrointestinal cancer. Data collection will take place at inclusion, after six months, after one year and every subsequent year until death or end of the study. Data will be collected through personal interviews (consisting of socio-demographic information, general health information, a comprehensive geriatric assessment, quality of life, health locus of control and a loneliness scale), a handgrip test, assessment of medical records, two buccal swabs and a blood sample from cancer patients (at baseline). As an annex study, caregivers of the participants will be recruited as well. Data collection for caregivers will consist of a self-administered questionnaire examining depression, coping, and burden.
This extensive data collection will increase insight on how wellbeing of older cancer patients is affected by cancer (diagnosis and treatment), ageing, and their interaction. Results may provide new insights, which might contribute to the improvement of care for older cancer patients.
BMC Public Health 01/2011; 11:825. · 2.00 Impact Factor
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ABSTRACT: Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system (CNS) in which macrophages play a central role. Initially, macrophages where thought to be merely detrimental in MS, however, recent evidence suggests that their functional phenotype is altered following myelin phagocytosis. Macrophages that have phagocytosed myelin may be less inflammatory and may exert beneficial effects. The presence of myelin-containing macrophages in CNS-draining lymph nodes and perivascular spaces of MS patients suggests that these cells are ideally positioned to exert an immune regulatory role. Therefore we evaluated in this study the effect of myelin-phagocytosing macrophages on lymphocyte reactivity.
Thioglycolate-elicited rat peritoneal macrophages were loaded with myelin and cocultured with myelin-basic protein (MBP) or ovalbumin (OVA) reactive lymphocytes. Lymphocyte proliferation was determined by CFSE-labeling. The role of nitric oxide in regulating lymphocyte proliferation was assessed by addition of an inhibitor of inducible nitric oxide synthase to the coculture. In vivo immune regulation was investigated by treating MBP- and OVA-immunized animals subcutaneously with myelin. Cognate antigen specific lymphocyte proliferation and nitric oxide production were determined 9 d post-immunization.
In this study we demonstrate that myelin-phagocytosing macrophages inhibit TCR-triggered lymphocyte proliferation in an antigen-independent manner. The observed immune suppression is mediated by an increase in NO production by myelin-phagocytosing macrophages upon contact with lymphocytes. Additionally, myelin delivery to primarily CD169+ macrophages in popliteal lymph nodes of OVA-immunized animals results in a reduced cognate antigen specific proliferation. In contrast to OVA-immunized animals, lymphocytes from MBP-immunized animals displayed an increased proliferation after stimulation with their cognate antigen, indicating that myelin-phagocytosing macrophages have dual effects depending on the specificity of surrounding lymphocytes.
Collectively our data show that myelin phagocytosis leads to an altered macrophage function that inhibits lymphocyte proliferation. Additionally, results from this study indicate that myelin-phagocytosing macrophages fulfill a dual role in vivo. On one hand they aggravate autoimmunity by activating myelin-reactive lymphocytes and on the other hand they suppress lymphocyte reactivity by producing NO.
Journal of Neuroinflammation 01/2011; 8:85. · 3.83 Impact Factor
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ABSTRACT: Resistance training studies in multiple sclerosis (MS) often use short intervention periods. Furthermore, training efficiency could be optimized by unilateral training and/or electrical stimulation.
To examine the effect(s) of unilateral long-term (20 weeks) standardized resistance training with and without simultaneous electro-stimulation on leg muscle strength and overall functional mobility.
A randomized controlled trial involving 36 persons with MS. At baseline (PRE) and after 10 (MID) and 20 (POST) weeks of standardized (ACSM) light to moderately intense unilateral leg resistance training (RES(O), n = 11) only or resistance training with simultaneous electro-stimulation (RES(E), n = 11, 100 Hz, biphasic symmetrical wave, 400 µs), maximal isometric strength of the knee extensors and flexors (45°, 90° knee angle) and dynamic (60-180°/s) knee-extensor strength was measured and compared with a control group (CON, n = 14). Functional mobility was evaluated using the Timed Get Up and Go, Timed 25 Foot Walk, Two-Minute Walk Test, Functional Reach and Rivermead Mobility Index.
Maximal isometric knee extensor (90°, MID: +10 ± 3%, POST: +10 ± 4%) in RES(O) and knee flexor (45°, POST: +7 ± 4%; 90°, POST: +9 ± 5%) in RES(E) strength increased (p < 0.05) compared with CON but RES(O) and RES(E) did not differ. Also, impaired legs responded positively to resistance training (unilateral leg strength analysis) and functional reaching increased significantly in RES(O) (+18%) compared with CON. Dynamic muscle strength and the remaining functional mobility tests did not change.
Long-term light to moderately intense resistance training improves muscle strength in persons with MS but simultaneous electro-stimulation does not further improve training outcome.
Multiple Sclerosis 12/2010; 17(4):468-77. · 4.26 Impact Factor
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ABSTRACT: Approximately one-third of rheumatoid arthritis (RA) patients are seronegative for the 2 serological RA markers, rheumatoid factor (RF) and antibodies against cyclic citrullinated peptides (ACCP). Moreover, the sensitivities of both markers are lower in the diagnostically important early disease phase. The aim of this study was to identify additional autoantibody markers for early RA and for RF-negative, ACCP-negative (seronegative) RA. We screened an RA synovium cDNA phage display library with autoantibodies in plasma from 10 early (symptoms of maximum 1 year) and 10 seronegative (RF-negative, ACCP-negative) RA patients with validation in 72 additional RA patients and 121 controls (38 healthy controls, 43 patients with other inflammatory rheumatic diseases, 20 osteoarthritis patients and 20 subjects with mechanical joint complaints). Fourteen novel autoantibodies were identified that showed a 54% sensitivity and 90% specificity for RA. For 11 of these autoantibodies, an exclusive presence was demonstrated in RA patients (100% specificity, 37% sensitivity) as compared to controls. All early RA patients were positive for at least one of the identified autoantibodies and antibody-positivity was associated with a shorter disease duration (P = 0.0087). 52% of RA patients who initially tested negative for RF and ACCP, tested positive for at least one of the 14 novel autoantibodies, resulting in a 19% increase in sensitivity compared to current serological testing. Moreover, 5 identified autoantibodies were detected more frequently in seronegative RA patients, indicating that these autoantibodies constitute novel candidate markers for this RA subtype. We demonstrated that the targets of 3 of these 5 autoantibodies had an increased expression in RA synovial tissue compared to control synovial tissue, pointing towards a biological rationale for these auto antibody targets in RA. In conclusion, we identified novel candidate autoantibody markers for RA that can be detected in early and seronegative RA patients indicating the potential added value for RA diagnostics.
Journal of Autoimmunity 11/2010; 36(1):33-46. · 7.37 Impact Factor
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ABSTRACT: Therapies for multiple sclerosis (MS) reduce the relapse rate but are unable to stop neurological decline. Here, we evaluate the potential of leukemia inhibitory factor (LIF) as a novel therapeutic in diseases with a neurodegenerative and inflammatory component, such as MS. LIF, which can be a proinflammatory cytokine, can also modulate the immune response in a beneficial way. Recent evidence demonstrates a crucial role of LIF in neuroprotection and axonal regeneration as well as the prevention of demyelination. Finally, LIF is an important survival factor for stem cells and neuronal precursors. Therefore, we propose that LIF is a potential therapeutic candidate for MS.
Trends in Molecular Medicine 11/2010; 16(11):493-500. · 10.35 Impact Factor
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ABSTRACT: Myelin-reactive T helper-17 cells are implicated in the pathogenesis of multiple sclerosis (MS). Here, we analyzed the reactivity of peripheral naive and memory conventional CD4(+)CD127(high) T cells (Tconv) of MS patients and healthy controls (HC) towards myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG) and tetanus toxoid (TT). Proliferative responses of Tconv cells towards MBP, MOG and TT were not significantly different between MS patients and HC. However, MBP and MOG but not TT reactive memory Tconv cells from MS patients, in contrast to HC, produced IL-17. These results suggest that myelin antigen reactive Th-17 cells are enriched in MS patients.
Journal of neuroimmunology 09/2010; 226(1-2):185-91. · 2.84 Impact Factor
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ABSTRACT: Glycine, an important inhibitory neurotransmitter in the mammalian central nervous system (CNS), has been shown to modulate peripheral immune cell responses. In that respect, glycine levels are increased in several neuroinflammatory disorders, such as amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS). In this study, we show that glycine modulates macrophage effector functions implicated in CNS inflammation and in other, related inflammatory conditions. We demonstrate that glycine does not affect the production of reactive oxygen species but stimulates myelin phagocytosis and the production of the proinflammatory mediators nitric oxide (NO) and tumor necrosis factor (TNF)-alpha by rat macrophages. These effects of glycine are not mediated by the glycine receptor (GlyR) or by glycine transporters (GlyTs), as neither the GlyR antagonist strychnine nor the antagonist of GlyT1 (ALX5407) reverses the observed effects. In contrast, 2-aminoisobutyric acid, a substrate of neutral amino acid transporters (NAATs), inhibits the glycine-mediated enhancement of myelin phagocytosis as well as of NO and TNF-alpha production. In conclusion, our findings demonstrate that glycine modulates macrophage function through activation of NAATs. Glycine may thereby influence immunological processes in inflammatory diseases involving macrophage activation and demyelination, including MS and related conditions associated with altered glycine levels.
Journal of Neuroscience Research 08/2010; 88(11):2420-30. · 2.74 Impact Factor
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ABSTRACT: Myelin-reactive T cells are responsible for initiating the cascade of autoreactive immune responses leading to the development of multiple sclerosis. For better insights into the disease mechanism, it is of major importance to have knowledge on the sites at which these cells are active during disease progression. Herein, we investigated the feasibility of tracking myelin-reactive T cells, upon labelled with SPIO particles, in the central nervous system (CNS) of experimental autoimmune encephalomyelitis (EAE) animals by MRI. First, we determined the optimal labelling condition leading to a high particle uptake and minimal SPIO-Poly-l-lysine (PLL) aggregate formation using Prussian blue staining and inductively coupled plasma spectroscopy measurements. Results from labelling of myelin reactive T cells with low concentrations of SPIO particles (i.e. 25 microg/ml) combined with different concentrations of PLL (0-1.5 microg/ml) showed that increasing amounts of PLL led to augmented levels of free remnant SPIO-PLL aggregates. In contrast, a low PLL concentration (i.e. 0.5 microg/ml) combined with high concentrations of SPIO (i.e. 400 microg Fe/ml) led to a high labelling efficiency with minimal amounts of aggregates. Second, the labelled myelin-reactive T cells were transferred to control rats to induce EAE. At the occurrence of hindlimb paralysis, the SPIO labelled myelin-reactive T cells were detected in the sacral part of the spinal cord and shown to be highly confined to this region. However, upon transfer in already primed rats, T cells were more widely distributed in the CNS and shown present in the spinal cord as well as in the brain. Our study demonstrates the feasibility of tracking SPIO labelled myelin-reactive T cells in the spinal cord as well as the brain of EAE rats upon systemic administration. Furthermore, we provide data on the optimal labelling conditions for T cells leading to a high particle uptake and minimal aggregate formation.
NMR in Biomedicine 07/2010; 23(6):601-9. · 3.21 Impact Factor
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ABSTRACT: Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) with an inflammatory and a neurodegenerative component. The neuropoietic cytokine leukemia inhibitory factor (LIF) is expressed in MS lesions, but its effect on lesion development is far from understood. LIF is an interesting candidate for MS therapy, as it has neuroprotective properties and may also promote the survival of myelinating oligodendrocytes (OLGs). However, therapeutic administration of LIF is complicated by its limited ability to cross the blood-brain barrier and its pleiotropic actions outside the CNS. In this study, lentiviral vectors (LVs) were used to achieve stable expression and secretion of LIF in the CNS of adult mice. CNS-targeted expression of LIF significantly reduced demyelination in a murine model of MS. In addition, local expression of LIF ameliorated clinical symptoms with enhanced efficacy compared to systemic treatment with recombinant protein. These findings demonstrate that gene therapeutic administration of LIF is a promising approach to limit lesion burden and clinical symptoms in neuroinflammatory disease.
Molecular Therapy 04/2010; 18(4):684-91. · 6.87 Impact Factor
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ABSTRACT: Myasthenia Gravis (MG) is an antibody-mediated autoimmune disorder affecting the postsynaptic membrane of the neuromuscular junction (NMJ). MG is characterized by an impaired signal transmission between the motor neuron and the skeletal muscle cell, caused by auto-antibodies directed against NMJ proteins. The auto-antibodies target the nicotinic acetylcholine receptor (nAChR) in about 90% of MG patients. In approximately 5% of MG patients, the muscle specific kinase (MuSK) is the auto-antigen. In the remaining 5% of MG patients, however, antibodies against the nAChR or MuSK are not detectable (idiopathic MG, iMG). Although only the anti-nAChR and anti-MuSK auto-antibodies have been demonstrated to be pathogenic, several other antibodies recognizing self-antigens can also be found in MG patients. Various auto-antibodies associated with thymic abnormalities have been reported, as well as many non-MG-specific auto-antibodies. However, their contribution to the cause, pathology and severity of the disease is still poorly understood. Here, we comprehensively review the reported auto-antibodies in MG patients and discuss their role in the pathology of this autoimmune disease.
Autoimmunity 04/2010; 43(5-6):380-400. · 2.47 Impact Factor
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ABSTRACT: The pathological features of multiple sclerosis (MS), a chronic inflammatory disorder of the central nervous system, support an autoimmune etiology. Strong evidence has been provided for a potential functional defect of CD4(+)CD25(+)FOXP3(+) regulatory T cells (Tregs) in patients with relapsing-remitting MS. More recently, alterations in homeostatic parameters related to the development and function of naive and memory-like Tregs were discovered in MS patients. In this review, we evaluate the evidence for disturbed Treg homeostasis in MS and discuss the role of potential compensatory mechanisms in the chronic disease phase. Better insights into the processes underlying the compromised immune regulation in MS patients will be important to understand the potential of Treg-based therapies.
Trends in Molecular Medicine 02/2010; 16(2):58-68. · 10.35 Impact Factor
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ABSTRACT: Phage display is a powerful technique that enables easy identification of targets for any type of ligand. Targets are displayed at the phage surface as a fusion protein to one of the phage coat proteins. By means of a repeated process of affinity selection on a ligand, specific enrichment of displayed targets will occur. In our studies using C-terminal display of cDNA fragments to phage coat protein p6, we noticed the occasional enrichment of targets that do not contain an open reading frame. This event has previously been described in other phage display studies using N-terminal display of targets to phage coat proteins and was due to uncommon translational events like frameshifting. The aim of this study was to examine if C-terminal display of targets to p6 is also subjected to frameshifting. To this end, an enriched target not containing an open reading frame was selected and an E-tag was coupled at the C-terminus in order to measure target display at the surface of the phage. The tagged construct was subsequently expressed in 3 different reading frames and display of both target and E-tag measured to detect the occurrence of frameshifting. As a result, we were able to demonstrate display of the target both in the 0 and in the +1 reading frame indicating that frameshifting can also take place when C-terminal fusion to minor coat protein p6 is applied.
Molecules 01/2010; 15(12):9380-90. · 2.39 Impact Factor
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ABSTRACT: A major focus in rheumatoid arthritis (RA) research is the identification of the antigens that are targeted by the joint-directed autoimmune response. B cells and associated autoantibodies have been studied in RA to identify the antigenic targets and to discover RA-associated autoantibodies which can be used as disease markers. This research indicated the heterogeneity of the autoantibody profile in RA and the large overlap in antibody specificities with other rheumatic diseases pointing toward the need for multiplexing to identify an RA-associated autoantibody profile. The discovery of antibodies directed against cyclic citrullinated peptides (ACPA) has led to great advances in RA research. This finding generated novel autoantigen suspects in ACPA-positive RA patients, which comprise approximately two-thirds of the entire RA population, namely citrullinated peptides and/or proteins. One-third of the RA patients, however, do not show ACPA, and it is now postulated that ACPA-positive and ACPA-negative RA are two different disease entities with different genetic associations, pathogenesis, and etiology. The analysis of autoantibodies in ACPA-negative RA could provide insight into the identity of antigenic targets and markers for this disease subtype. We report here the optimization of an unbiased, high-throughput autoantibody profiling procedure based on cDNA phage display for the detection of novel autoantibody targets in ACPA-negative RA. The discovery of specific autoantibodies in this RA subtype could lead to great advances in the diagnosis of these patients and could provide clues regarding disease etiology and pathogenesis of ACPA-negative RA.
Annals of the New York Academy of Sciences 09/2009; 1173:92-102. · 3.15 Impact Factor
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ABSTRACT: The preliminary positive effects of B cell depletion therapy in multiple sclerosis (MS) have renewed interest in a potential role of B cells and autoantibodies in the MS disease process. Regardless of a possible pathogenic role of the humoral immune response in MS, the analysis of autoantibodies as disease markers is valuable. Despite intense research, there is no known MS-associated antibody specificity that can individually discriminate between MS patients and controls. Due to the overlap in autoantibody profiles in autoimmune diseases, and due to the complexity of MS, multiplex autoantibody profiling approaches are needed to generate a panel of MS-associated autoantibodies with high combined sensitivity and specificity for MS. In recent years, several multiplexing approaches have been applied in MS autoantibody profiling with promising results regarding the generation of a so-called MS-specific autoantibody fingerprint. We also recently applied a high-throughput autoantibody profiling technique for MS cerebrospinal fluid resulting in the identification of a novel panel of 8 antigenic targets with 45% sensitivity and 86% specificity for the disease. Identification of MS-specific autoantibody specificities is important for the development of diagnostic and prognostic markers for MS. Moreover, it can provide more knowledge regarding underlying MS disease processes and novel therapeutic targets.
Autoimmunity reviews 03/2009; 8(7):573-9. · 6.37 Impact Factor
