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  • Article: Loss of purkinje cells is associated with demyelination in multiple sclerosis.
    The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques 05/2011; 38(3):529-31. · 0.97 Impact Factor
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    Article: Intravenous synthetic peptide MBP8298 delayed disease progression in an HLA Class II-defined cohort of patients with progressive multiple sclerosis: results of a 24-month double-blind placebo-controlled clinical trial and 5 years of follow-up treatment.
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    ABSTRACT: MBP8298 is a synthetic peptide with a sequence corresponding to amino acid residues 82-98 of human myelin basic protein (DENPVVHFFKNIVTPRT). It represents the immunodominant target for both B cells and T cells in multiple sclerosis (MS) patients with HLA haplotype DR2. Its administration in accordance with the principle of high dose tolerance results in long-term suppression of anti-myelin basic protein (MBP) autoantibody levels in the cerebrospinal fluid (CSF) of a large fraction of progressive MS patients. MBP8298 was evaluated in a 24-month placebo-controlled double-blinded Phase II clinical trial in 32 patients with progressive MS. The objective was to assess the clinical efficacy of 500 mg of MBP8298 administered intravenously every 6 months, as measured by changes in Expanded Disability Status Scale (EDSS) scores. Contingency analysis for all patients at 24 months showed no significant difference between MBP8298 and placebo-treatments (n = 32, P = 0.29). Contingency analysis in an HLA Class II defined subgroup showed a statistically significant benefit of MBP8298 treatment compared with placebo in patients with HLA haplotypes DR2 and/or DR4 (n = 20, P = 0.01). Long-term follow-up treatment and assessment of patients in this responder group showed a median time to progression of 78 months for MBP8298 treated patients compared with 18 months for placebo-treatment (Kaplan-Meier analysis, P = 0.004; relative rate of progression = 0.23). Anti-MBP autoantibody levels in the CSF of most MBP8298 treated patients were suppressed, but antibody suppression was not predictive of clinical benefit. Anti-MBP autoantibodies that reappeared in the CSF of one patient at 36 months, whilst under treatment with MBP8298, were not reactive with the MBP8298 peptide in vitro. The identification of a responder subgroup (62.5% of the patients in this study) enables a more efficient design of a large confirmatory clinical trial of MBP8298. The probability that patients with other less common HLA-DR haplotypes will respond to this treatment should not be ignored.
    European Journal of Neurology 09/2006; 13(8):887-95. · 3.69 Impact Factor
  • Article: Kinetic profiles of cerebrospinal fluid anti-MBP in response to intravenous MBP synthetic peptide DENP(85)VVHFFKNIVTP(96)RT in multiple sclerosis patients.
    K G Warren, I Catz
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    ABSTRACT: Multiple sclerosis [MS], a demyelinating disease of the central nervous system associated with inflammation and gliosis, may be an autoimmune disease with T lymphocytes and autoantibodies to myelin protein(s). This study deals exclusively with B cell autoimmunity to myelin basic protein (MBP). T lymphocytes and anti-MBP share a common MBP epitope located between P(85) and P(96) which contains the essential contact residues H(88)FFK(91) for the trimolecular complex. The purpose of this Phase I open label clinical study was to monitor CSF anti-MBP in patients with chronic progressive MS subsequent to IV administration of synthetic peptide (sp) MBP82-98 namely DEN(85)VVHFFKNIVTP(96)RT. Fifty-six patients who participated in this project were assigned to two groups: a 'control group' of 15 patients who received IV saline injections every 6 months for the first 2 years of the study and a 'peptide group' of 41 patients who received IV spMBP82-98 from the beginning of the study and then infrequently subsequent to a rise of their CSF anti-MBP. In the control group antibody levels remained persistently elevated during the 2 year period. Patients in the 'peptide group' segregated into four kinetic profiles: Cohort A (15 patients) illustrated prolonged anti-BMP suppression into the normal range. Cohort B (10 patients) illustrated significant anti-MBP suppression into the normal range for shorter durations. Cohort C (eight patients) showed significant CSF anti-MBP suppression after the initial injection but lost the ability to suppress the autoantibody titer following subsequent injections. Cohort D (eight patients) failed to show significant CSF anti-MBP suppression. In conclusion the B cell tolerizing effect of spMBP82-98 segregated into four kinetic profiles; this molecular variability should be considered in attempts to develop specific 'peptide therapies' for the broad range of clinical profiles currently diagnosed as 'multiple sclerosis'. Multiple Sclerosis (2000) 6 300 - 311
    Multiple Sclerosis 11/2000; 6(5):300-11. · 4.26 Impact Factor
  • Article: An extensive search for autoantibodies to myelin basic protein in cerebrospinal fluid of non-multiple-sclerosis patients: implications for the pathogenesis of multiple sclerosis.
    K G Warren, I Catz
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    ABSTRACT: Inflammation of multiple sclerosis (MS) brain and spinal cord tissue consists of macrophages, T lymphocytes and cytokines as well as B lymphocytes and immunoglobulins (IgGs). IgG can be detected in high concentrations in both central nervous system tissue and cerebrospinal fluid (CSF). Using a sensitive radioimmunoassay (RIA), autoantibodies to myelin basic protein (anti-MBP) can be detected in the CSF of 90-95% of MS patients with active disease. The purpose of the present report was to determine whether these same autoantibodies can be reliably detected in non-MS patients. Between 1978 and 1998, CSF was collected from 1,968 control non-MS patients with psychiatric, inflammatory and noninflammatory neurological diseases as well as nonneurological systemic diseases, and anti-MBP were measured by the same RIA used to detect anti-MBP in MS CSF. Anti-MBP were undetectable in 98% of CSF samples from non-MS controls. In the remaining 2% of control samples, CSF IgGs capable of binding to MBP in vitro were unpredictably detected. This latter group included 1% of patients with miscellaneous diseases such as encephalomyelitis, 5 siblings with familial spastic paraparesis, rare patients with strokes, Wernicke-Korsakoff's syndrome, inherited leukodystrophy, motor neuron disease and some patients with miscellaneous spinal cord diseases. An additional 1% of patients included a group with neurological symptoms suggestive of early or predisseminated MS. The high prevalence of free and/or bound anti-MBP in the CSF of MS patients and the rare and unpredictable occurrence in the CSF of non-MS patients suggest that autoimmunity to MBP may be operative in the demyelination of MS. Molecular clones of anti-MBP with specificity towards variable surface or cryptic MBP epitopes in vivo may determine whether or not they are involved in the demyelinating process, and this variability may also be present within the MS population. Potential mechanisms of anti-MBP-mediated demyelination in MS patients are discussed.
    European Neurology 02/1999; 42(2):95-104. · 1.81 Impact Factor
  • Article: Tolerance induction to myelin basic protein by intravenous synthetic peptides containing epitope P85 VVHFFKNIVTP96 in chronic progressive multiple sclerosis.
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    ABSTRACT: Peptide-based tolerance induction may be useful for antigen-specific immunotherapy of human autoimmune diseases. Induction of tolerance to myelin basic protein (MBP) was examined in a Phase I clinical trial in multiple sclerosis (MS) patients with chronic progressive disease using a peptide that is immunodominant for MBP specific T cells and B cells. Tolerance induction was monitored by quantification of MBP specific autoantibodies in cerebrospinal fluid (CSF). The route of peptide administration was important since only intravenous but not intrathecal or subcutaneous injection induced tolerance to MBP. Following a single intravenous injection of a peptide containing epitope P85VVHFFKNIVTP96, MBP autoantibodies were undetectable for three to four months. Tolerance was more prolonged following a second injection since autoantibodies were low or undetectable after one year in the majority of patients. Duration of tolerance to MBP depended on MHC class II haplotypes of patients; tolerance was long-lived in all patients with disease associated HLA-DR2. No neurological or systemic side effects were observed, regardless of the route of peptide administration. These data demonstrate that intravenous administration of a soluble peptide can result in long-lasting tolerance to an autoantigen in humans.
    Journal of the Neurological Sciences 12/1997; 152(1):31-8. · 2.35 Impact Factor

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