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Review Tovaxin, radiation-attenuated, patient-specific T-cells for the therapeutic vaccination of multiple sclerosis. 2008
Hellings N, Stinissen P. · Hasselt University, Biomedical Research Institute, Agoralaan Building A, Diepenbeek B-3590, Belgium. · Curr Opin Investig Drugs. · Pubmed #18465664 No free full text.
Abstract: Opexa Pharmaceuticals Inc is developing Tovaxin, a trivalent formulation of attenuated myelin-peptide-reactive T-cells, for the potential treatment of multiple sclerosis. Tovaxin is being evaluated in phase II clinical trials. Opexa was previously investigating Tovaxin for the potential treatment of rheumatoid arthritis; however, no development has been reported for this indication since December 2002.
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Review The autoimmune pathogenesis of rheumatoid arthritis: role of autoreactive T cells and new immunotherapies. 2001
VanderBorght A, Geusens P, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut DWI, Limburgs Universitair Centrum, Diepenbeek, Belgium. · Semin Arthritis Rheum. · Pubmed #11740797 No free full text.
Abstract: OBJECTIVES: To review the role of T lymphocytes in the pathogenesis of rheumatoid arthritis (RA) and discuss the relevance of the components of the trimolecular complex (synovial T cells, autoantigens, and antigen presenting cells) in the pathogenic autoimmune response in RA. METHODS: Currently available experimental data are combined into a hypothetical pathway that may explain some of the events in the RA process. The literature regarding the potential therapeutic strategies that interfere with specific components of the trimolecular complex and other mediators are discussed briefly. RESULTS: T cells are activated in the peripheral blood, cross the endothelial cell wall, and migrate into the joints. Once in the synovial joints, T cells are reactivated by cross-reactive antigens and clonally expand. Clonally expanded T cells accumulate in the diseased joint and secrete proinflammatory cytokines that attract and activate other cells, such as monocytes and macrophages. Treatment with anti-CD4 monoclonal antibodies or anticytokine agents that prevents antigen presentation and/or T-cell activation were effective in RA. Other therapies, such as T-cell vaccination and T-cell receptor peptide vaccination targeting autoreactive T cells, showed clinical improvement, suggesting a pathogenic role of these lymphocytes in disease progression. CONCLUSION: T cells appear to be actively involved in the pathogenesis of RA, but several parts of the pathway are hypothetical and further research is needed.
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Clinical Conference Dynamic T cell receptor clonotype changes in synovial tissue of patients with early rheumatoid arthritis: effects of treatment with cyclosporin A (Neoral). 2002
VanderBorght A, De Keyser F, Geusens P, De Backer M, Malaise M, Baeten D, Van den Bosch F, Veys EM, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut DWI, Limburgs Universitair Centrum, Diepenbeek, Belgium. · J Rheumatol. · Pubmed #11908552 No free full text.
Abstract: OBJECTIVE: To study T cell receptor (TCR) repertoire changes in synovial membrane over a 16 week period in patients with early rheumatoid arthritis (RA); and to study the influence of cyclosporin A (CSA) on TCR repertoire in a subgroup of these patients. METHODS: Synovial tissue biopsies and paired blood samples were obtained from 12 patients with early RA at 2 time points. Seven patients were treated with CSA (Neoral-Sandimmun, 3 mg/kg/day) and 5 patients with placebo for 16 weeks. TCR V gene repertoires were analyzed by semiquantitative PCR-ELISA. CDR3 spectratyping and sequence analysis was used to compare TCR clonotype distributions. RESULTS: TCR-specific mRNA was detected in all synovial tissue biopsies at the first sampling, but in only 8/12 biopsies 16 weeks later (4/7 CSA group, 4/5 placebo group). Overrepresented TCR BV genes were found in biopsies of 10/12 patients at the first time point, and in 7/12 patients after 16 weeks (3/7 CSA, 4/5 placebo). CDR3 sequence analysis revealed dynamic repertoire changes with only a few persisting clonotypes in the synovial tissue of placebo controls. Persisting T cell clonotypes were more frequently found in the synovial tissue of CSA treated patients compared to the placebo group. CONCLUSION: These data suggest a dynamic process of T cell recruitment in the joints of RA patients. This process, possibly due to activation and subsequent infiltration of new T cell clones, apparently is influenced by CSA treatment. Synovial tissue T cells were no longer detected after 16 weeks' CSA treatment in 3 patients. In the other CSA treated patients, new T cell clones infiltrated, while other clones were persistently represented in the joints. These data may have important consequences for the design of T cell targeted therapies for RA.
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Article CD4+CD28null T cells in autoimmune disease: pathogenic features and decreased susceptibility to immunoregulation. free! 2007
Thewissen M, Somers V, Hellings N, Fraussen J, Damoiseaux J, Stinissen P. · Hasselt University, Biomedical Research Institute, Transnationale Universiteit Limburg, Diepenbeek, Belgium. · J Immunol. · Pubmed #17982040 links to free full text
Abstract: To determine the role of expanded CD4(+)CD28(null) T cells in multiple sclerosis and rheumatoid arthritis pathology, these cells were phenotypically characterized and their Ag reactivity was studied. FACS analysis confirmed that CD4(+)CD28(null) T cells are terminally differentiated effector memory cells. In addition, they express phenotypic markers that indicate their capacity to infiltrate into tissues and cause tissue damage. Whereas no reactivity to the candidate autoantigens myelin basic protein and collagen type II was observed within the CD4(+)CD28(null) T cell subset, CMV reactivity was prominent in four of four HC, four of four rheumatoid arthritis patients, and three of four multiple sclerosis patients. The level of the CMV-induced proliferative response was found to be related to the clonal diversity of the response. Interestingly, our results illustrate that CD4(+)CD28(null) T cells are not susceptible to the suppressive actions of CD4(+)CD25(+) regulatory T cells. In conclusion, this study provides several indications for a role of CD4(+)CD28(null) T cells in autoimmune pathology. CD4(+)CD28(null) T cells display pathogenic features, fill up immunological space, and are less susceptible to regulatory mechanisms. However, based on their low reactivity to the autoantigens tested in this study, CD4(+)CD28(null) T cells most likely do not play a direct autoaggressive role in autoimmune disease.
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Article Analyses of immunosenescent markers in patients with autoimmune disease. 2007
Thewissen M, Somers V, Venken K, Linsen L, van Paassen P, Geusens P, Damoiseaux J, Stinissen P. · Hasselt University, Biomedical Research Institute and Transnationale Universiteit Limburg, School of Life Sciences, Agoralaan, Diepenbeek, Belgium, and Department of Clinical and Experimental Immunology, University Hospital Maastricht, The Netherlands. · Clin Immunol. · Pubmed #17317320 No free full text.
Abstract: The objective of this study was to evaluate the degree of immunosenescence in patients with autoimmune disease. T cell receptor excision circles (TREC) and the percentage of CD4+CD28null T cells were studied as markers of immunosenescence in 175 patients with chronic autoimmune arthritis, other connective tissue autoimmune diseases, multiple sclerosis and 60 healthy controls. In both the rheumatoid arthritis (RA) and multiple sclerosis patient group, TREC numbers were age-inappropriately declined which points to an accelerated thymic output. Furthermore, enhanced percentages of CD4+CD28null T cells could be detected in a significant proportion of patients included in this study. These immunosenescent phenomena seemed to be present already early in the disease process. High percentages of CD4+CD28null T cells were associated with the presence of RA linked HLA DR4 alleles and with plasma reactivity to cytomegalovirus. Further analysis of CD4+CD28null T cells provided indications for a restricted T cell receptor (TCR) BV gene expression and cytoplasmic stores of various cytotoxic molecules. This study indicates that the immune system of patients with autoimmune diseases shows signs of an accelerated aging. Both genetic factors, such as HLA DR4, and environmental factors, like CMV infection, might speed up this immunosenescence and contribute in this way to disease pathogenesis.
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Article The ratio of circulating osteoprotegerin to RANKL in early rheumatoid arthritis predicts later joint destruction. free! 2006
Geusens PP, Landewé RB, Garnero P, Chen D, Dunstan CR, Lems WF, Stinissen P, van der Heijde DM, van der Linden S, Boers M. · University Hospital, Maastricht, The Netherlands. · Arthritis Rheum. · Pubmed #16736519 links to free full text
Abstract: OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease that may result in debilitating joint deformities with destruction of bone and cartilage. Inflammation is still considered the pivotal inducer of both components of joint damage. Results of recent animal studies suggested a prominent contribution of osteoclastic bone resorption that could be dissociated from inflammation. RANKL and its natural decoy receptor, osteoprotegerin (OPG), play key roles in osteoclast activation. In a group of patients with early RA not treated with disease-modifying drugs, we tested the hypothesis that osteoclast activation, reflected by the serum OPG:RANKL ratio at baseline, is negatively associated with progression of bone damage, independent of inflammation. METHODS: OPG and RANKL levels, together with a parameter of inflammation (first-year time-averaged erythrocyte sedimentation rate [tESR]), were measured in 92 patients with newly diagnosed early active RA who were participants in a randomized study. The tESR and the OPG:RANKL ratio were evaluated for the ability to predict 5-year radiographic progression of joint damage. RESULTS: The first-year tESR and the OPG:RANKL ratio, as measured at baseline, independently predicted 5-year radiographic progression of joint damage (both P < or = 0.001). Progression of radiographic damage was greatest in patients with a high tESR and a low OPG:RANKL ratio and was lowest in patients with a low tESR and a high OPG:RANKL ratio. CONCLUSION: This study in patients with early untreated RA is the first to confirm the findings in animal models of arthritis, that radiographic progression of the bone component of joint destruction is dependent on both inflammation (tESR) and osteoclast activation (the OPG:RANKL ratio).
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Article No association of leukemia inhibitory factor (LIF) DNA polymorphisms with multiple sclerosis. 2006
Vanderlocht J, Burzykowski T, Somers V, Stinissen P, Hellings N. · Biomedical Research Institute, Hasselt University and Transnational University Limburg, Diepenbeek, Belgium. · J Neuroimmunol. · Pubmed #16263181 No free full text.
Abstract: Neuropoietins such as leukemia inhibitory factor (LIF) have been shown to ameliorate experimental autoimmune encephalomyelitis (EAE) and promote oligodendrocyte survival in vivo. We tested whether two previously described LIF polymorphisms are associated with MS by genotyping these single nucleotide polymorphisms (SNPs) in a group of MS patients (n=110), rheumatoid arthritis (RA) patients (n=120) and healthy controls (HC, n=109). Similar allele and genotype frequencies for both SNPs were found for all study groups. Furthermore, no associations with MS type or HLA-DR2 expression could be found. In summary, no association was found between the studied LIF DNA polymorphisms and the prevalence of MS indicating that these polymorphisms are not involved in determining disease susceptibility.
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Article Impaired activation-induced telomerase activity in PBMC of early but not chronic rheumatoid arthritis patients. 2005
Thewissen M, Linsen L, Geusens P, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut, Limburgs Universitair Centrum and School of Life Sciences, Transnationale Universiteit Limburg, Universitaire Campus, B-3590 Diepenbeek, Belgium. · Immunol Lett. · Pubmed #16154497 No free full text.
Abstract: Although telomerase activity is important in normal immune function, it is unclear whether telomerase or telomerase (dys)regulation plays a role in the pathogenic immune response in autoimmune diseases like rheumatoid arthritis (RA). In this study, we evaluated the dynamics of the activation-induced human telomerase reverse transcriptase (hTERT) response in RA patients and non-RA controls. The expression of the catalytic subunit of telomerase, hTERT, was measured in peripheral blood mononuclear cells (PBMC) of RA patients and controls after in vitro stimulation with anti-CD3 monoclonal antibody (mAb) using real-time PCR. Anti-CD3 mAb stimulation induced activation and proliferation of the T cells in all populations studied. In early RA patients with a disease duration of less than 1 year, the activation-induced hTERT mRNA levels were found to be reduced as compared to healthy controls (HC). Chronic RA patients, with a disease duration of more than 1 year, did not show these impaired hTERT mRNA levels after stimulation with anti-CD3 mAb. Decreased hTERT mRNA levels were also found in multiple sclerosis patients and patients suffering from flu-like symptoms, indicating that these deviations are not disease-specific. The impaired activation-induced hTERT response in PBMC may be a general response of the immune cells in cases of acute or chronic immune activation, presumably to control unwanted clonal expansions and to maintain the diversity of the TCR repertoire. Our results also indicate that clonal T cell expansions, described in RA, are probably not mediated by an elevated potency to express hTERT.
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Article Premature immunosenescence in rheumatoid arthritis and multiple sclerosis patients. 2005
Thewissen M, Linsen L, Somers V, Geusens P, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut, Limburgs Universitair Centrum, Universitary Campus, B-3590 Diepenbeek, Belgium. · Ann N Y Acad Sci. · Pubmed #16126966 No free full text.
Abstract: Patients with T-cell-mediated autoimmune diseases show immune system abnormalities that resemble the typical characteristics of autoimmune dysfunction described in the elderly. In addition, the incidence of autoimmune disease increases with advancing age. To evaluate whether patients with rheumatoid arthritis (RA) and multiple sclerosis (MS) have premature immuno-senescence, we measured two indicators of aging: the number of T-cell-receptor excision circles (TRECs) and the percentage of CD4+CD28(null) T cells. We studied them in the peripheral blood mononuclear cells (PBMCs) of 60 RA patients, 32 MS patients, and 40 healthy controls (HCs). We found that TREC numbers were lower in RA and MS patients than in age-matched HCs, indicating premature thymic involution. Moreover, a subset of these patients contained age-inappropriate high frequencies of CD4+CD28(null) T cells. This study provides evidence of premature immune system senescence in both RA and MS patients. Premature aging could be a risk factor for developing autoimmune disorders in genetically predisposed individuals in a susceptible environment.
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Article Peripheral blood but not synovial fluid natural killer T cells are biased towards a Th1-like phenotype in rheumatoid arthritis. free! 2005
Linsen L, Thewissen M, Baeten K, Somers V, Geusens P, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut, Limburgs Universitair Centrum and School of Life Sciences, Transnationale Universiteit Limburg, Universitaire Campus, Diepenbeek, Belgium. · Arthritis Res Ther. · Pubmed #15899036 links to free full text
Abstract: Natural killer T (NKT) cells have been implicated in the regulatory immune mechanisms that control autoimmunity. However, their precise role in the pathogenesis of rheumatoid arthritis (RA) remains unclear. The frequency, cytokine profile and heterogeneity of NKT cells were studied in peripheral blood mononuclear cells (PBMCs) from 23 RA patients and 22 healthy control individuals, including paired PBMC-synovial fluid samples from seven and paired PBMC-synovial tissue samples from four RA patients. Flow cytometry revealed a decreased frequency of NKT cells in PBMCs from RA patients. NKT cells were present in paired synovial fluid and synovial tissue samples. Based on the reactivity of PBMC-derived NKT cells toward alpha-galactosylceramide, RA patients could be divided into responders (53.8%) and nonresponders (46.2%). However, NKT cells isolated from synovial fluid from both responders and nonresponders expanded upon stimulation with alpha-galactosylceramide. Analysis of the cytokine profile of CD4+ and CD4- PBMC derived NKT cell lines from RA patients revealed a significantly reduced number of IL-4 producing cells. In contrast, synovial fluid derived NKT cell lines exhibited a Th0-like phenotype, which was comparable to that in healthy control individuals. This suggests that synovial fluid NKT cells are functional, even in patients with nonresponding NKT cells in their blood. We conclude that, because the number of Valpha24+Vbeta11+CD3+ NKT cells is decreased and the cytokine profile of blood-derived NKT cells is biased toward a Th1-like phenotype in RA patients, NKT cells might be functionally related to resistance or progression of RA. Providing a local boost to the regulatory potential of NKT cells might represent a useful candidate therapy for RA.
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Article Osteoprotegerin and receptor activator of nuclear factor-kappaB ligand mRNA expression in patients with rheumatoid arthritis and healthy controls. 2004
Vanderborght A, Linsen L, Thewissen M, Geusens P, Raus J, Stinissen P. · Limburgs Universitair Centrum, Biomedisch Onderzoeksinstituut, Diepenbeek, Belgium. · J Rheumatol. · Pubmed #15290725 No free full text.
Abstract: OBJECTIVE: To further understand the role of osteoprotegerin (OPG) and receptor activator of nuclear factor-kappaB ligand (RANK-L) in rheumatoid arthritis (RA), we studied the levels of RANK-L and OPG mRNA in peripheral blood mononuclear cells (PBMC) and synovial tissue of patients with RA and controls. METHODS: RANK-L and OPG mRNA levels were measured in PBMC and CD4+/CD8+ T cell subsets of patients with chronic RA, osteoarthritis (OA), and healthy controls, using quantitative real-time polymerase chain reaction. OPG and RANK-L mRNA levels were measured in paired blood and synovial tissue samples of patients with early, untreated RA at 2 timepoints with an interval of 16 weeks. RESULTS: RANK-L mRNA levels were significantly higher in PBMC of patients with early and chronic RA compared to healthy controls. Contrary to healthy controls, RANK-L mRNA levels in patients with chronic RA were mainly of CD4+ T cell origin. OPG mRNA was observed in the blood of all (17/17) early RA patients, but could not be detected in chronic RA patients (0/14) or in patients with OA (0/8). Three out of 17 healthy controls showed measurable levels of OPG mRNA. The OPG/RANK-L ratio tended to be higher in the synovium than in the PBMC of early RA patients. RANK-L mRNA in synovial tissue was mainly of non-T cell origin. CONCLUSION: Since RANK-L and OPG mRNA levels are elevated in PBMC of RA patients, and CD4+ T cells are the major contributors to RANK-L mRNA expression, mononuclear cells in patients with RA may be involved in the pathways that regulate bone metabolism.
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Article Interferon-gamma-induced calcium influx in T lymphocytes of multiple sclerosis and rheumatoid arthritis patients: a complementary mechanism for T cell activation? 2002
Buntinx M, Ameloot M, Steels P, Janssen P, Medaer R, Geusens P, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut, Limburgs Universitair Centrum and School of Life Sciences, Transnational University Limburg, Universitaire Campus gebouw A, B-3590 Diepenbeek, Belgium. · J Neuroimmunol. · Pubmed #11958824 No free full text.
Abstract: Autoreactive T lymphocytes are considered to play a crucial role in orchestrating a chronic inflammation in the central nervous system (CNS) of multiple sclerosis (MS) patients and in the joints of rheumatoid arthritis (RA) patients. However, it has been suggested that the majority of T cells in the immune infiltrate are nonspecifically recruited into the CNS and into the inflamed joint. In addition, several lines of evidence suggest an important role for interferon-gamma (IFN-gamma) in the pathogenesis of MS and RA. We have studied whether peripheral blood T cells from patients with autoimmune diseases are more susceptible to activation in the presence of IFN-gamma. The results indicate that IFN-gamma mediates a sustained elevated [Ca(2+)](i) in T cells of (active) MS and RA patients as compared to healthy controls and patients with common viral infections. No [Ca(2+)](i) increase was observed in Ca(2+)-free medium, excluding an effect of IFN-gamma on Ca(2+)-release from intracellular stores. Although the IFN-gamma-activated Ca(2+)-influx is insufficient to induce T cell proliferation in vitro, our data indicate a significantly augmented proliferation in response to suboptimal doses of PHA in the presence of IFN-gamma. This study suggests that the IFN-gamma-induced Ca(2+)-influx can act as a complementary mechanism in the activation of blood T lymphocytes from MS and RA patients.
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Article Skewed T-cell receptor variable gene usage in the synovium of early and chronic rheumatoid arthritis patients and persistence of clonally expanded T cells in a chronic patient. free! 2000
VanderBorght A, Geusens P, Vandevyver C, Raus J, Stinissen P. · Biomedisch Onderzoeksinstituut DWI, Limburgs Universitair Centrum, Diepenbeek, Belgium. · Rheumatology (Oxford). · Pubmed #11085796 links to free full text
Abstract: OBJECTIVE: Autoreactive T cells may contribute to the pathogenesis of rheumatoid arthritis (RA). We studied the T-cell receptor (TCR) V-gene repertoire in the blood and synovium of early and chronic RA patients using polymerase chain reaction-enzyme-linked immunosorbent assay to evaluate possible differences between these patient groups. RESULTS: Over-represented TCR V genes were observed in the synovium, but not in the blood of all RA patients (n = 38). The number of over-represented V genes was higher in the synovium of chronic RA patients (n = 31) than in that of early RA patients (n = 7). The V-gene profile was different among patients, and similar in the two knees for patients with bilateral synovitis (n = 5). The clonal composition of over-represented TCR BV genes in a patient with early RA and a patient with chronic RA was further studied by CDR3 region sequence analysis. A high level of clonal diversity was found in the joints and the blood of the early RA patient, suggesting a polyclonal T-cell expansion. In the chronic RA patient, predominant clonal expansions were observed in the blood and synovium, and some expanded clones were still present 2 yr later. CONCLUSIONS: The observation of similar T-cell populations in both joints in patients with bilateral synovitis and the persistence of clonally expanded T cells for more than 2 yr in the joints of a chronic RA patient may indicate a pathogenic role for these cells in the disease process.
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Article Identification of overrepresented T cell receptor genes in blood and tissue biopsies by PCR-ELISA. 1999
VanderBorght A, van der Aa A, Geusens P, Vandevyver C, Raus J, Stinissen P. · Department of Autoimmune Disease, Dr. L. Willems-Instituut, Diepenbeek, Belgium. · J Immunol Methods. · Pubmed #10037234 No free full text.
Abstract: The analysis of T cell receptor variable (TCR V) gene repertoires in blood or tissues may provide important information when studying immunopathological mechanisms. The overexpression of a TCR gene may indicate the expansion of the corresponding T cell subset. In autoimmune diseases, clonally expanded T cell subsets in the affected organs may represent pathogenic lymphocytes. We describe a simple, rapid and sensitive method to determine the TCR AV and BV gene repertoire using a PCR-ELISA method. RNA is extracted from lymphocytes, transcribed to cDNA, which is then used as a template for PCR with 19 different TCR AV gene and 20 BV gene specific primers as the forward primer, and a digoxigenin (DIG) labeled AC/BC primer as the reverse primer. The DIG labeled PCR amplicons are hybridized with a fluorescein isothiocyanate (FITC) labeled TCR C region specific probe. Finally, the amplicons are quantified by ELISA using anti-FITC coated microtiter plates, and an anti-DIG conjugated peroxidase. Although PCR-ELISA cannot accurately quantify the expression level of a given TCR gene, overrepresented TCR V genes are easily identified by comparing the relative expression levels of each individual V gene in the total V gene repertoire. We demonstrate that this technique can be used to determine TCR profiles in blood and tissue samples containing as few as 50,000 T cells. In combination with CDR3 fragment size analysis, this method is an efficient tool to identify clonally expanded T cell subsets in the synovial biopsies of rheumatoid arthritis patients.
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