Publications by authors named "Minako Oshima"

We have recently mapped the in vitro proliferative responses of T cells from botulinum neurotoxin type A (BoNT/A)-treated cervical dystonia (CD) patients with overlapping peptides encompassing BoNT/A heavy chain (residues 449-1296). In the present study, we determined the recognition profiles, by peripheral blood lymphocytes (PBL) from the same set of patients, of BoNT/A light (L) chain (residues 1-453) by using 32 synthetic overlapping peptides that encompassed the entire L chain. Profiles of the T-cell responses (expressed in stimulation index, SI; Z score based on transformed SI) to the peptides varied among the patients.

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Experimental autoimmune myasthenia gravis (EAMG), an animal model of myasthenia gravis (MG), can be induced in C57BL/6 (B6, H-2 ) mice by 2-3 injections with Torpedo californica AChR (tAChR) in complete Freund's adjuvant. Some EAMG mice exhibit weight loss with muscle weakness. The loss in body weight, which is closely associated with bone structure, is particularly evident in EAMG mice with severe muscle weakness.

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Previously, we have examined the proliferative responses of T-cells from 25 patients and 8 controls to 32 light chain (L1-L32) and 60 heavy chain peptides (N1-N29, C1-C31) representing the entire clostridium botulinum neurotoxin type A (BoNT/A)[OM1-OM3]. In the current work, these T-cell responses were analyzed in the context of the patients HLA-DRB1, DQA1 and DQB1 variation. There were strong associations between the DQA1*01:02 and its derived haplotypes and cumulative T-cell proliferative responses.

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An animal model of myasthenia gravis (MG), termed experimental autoimmune MG (EAMG), is an important tool for investigations of disease mechanisms and/or methods of treatment for this disease. EAMG can be induced in C57BL/6 (B6, H-2) mice by 2-3 times injections at 4 weeks intervals with Torpedo californica (t) acetylcholine receptor (AChR) in complete Freund's adjuvant (CFA). However, the protocol especially with a two-injection schedule occasionally produces a poor incidence of EAMG.

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We have conducted a 26-month-long comparative study involving young patients (2-6years old) with a clinical diagnosis of spastic equinus secondary to cerebral palsy who have been treated with BoNT/A (BOTOX®, Allergan) tri-annually or annually. Serum samples were obtained to determine the presence or absence of blocking antibodies (Abs) by a mouse protection assay (MPA) and levels of anti-BoNT/A Abs by radioimmune assay (RIA). HLA DQ alleles were typed using blood samples to determine the possible association of certain HLA type(s) with the disease or with the Ab status.

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We have recently reported the submolecular T-cell recognition profile of the C-terminal half (H, residues 855-1296) of the heavy (H) chain of botulinum neurotoxin type A (BoNT/A) with peripheral blood lymphocytes (PBL) from 25 BoNT-treated cervical dystonia (CD) patients. In the current study, we describe the mapping of the T-cell responses of the patients to the N-terminal half (H residues 449-859) of the heavy chain by using 29 synthetic overlapping peptides encompassing the entire H domain of BoNT/A. The profiles of the T-cell responses to the peptides varied among the patients.

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We determined the T-cell proliferative responses of the peripheral blood lymphocytes (PBL) from 25 botulinum neurotoxin (BoNT)-treated patients to 31 overlapping synthetic peptides encompassing the C-terminal half (residues 855-1296) of BoNT/A heavy chain. Responses of PBL to HC peptides varied among patients. Samples from 14 patients treated solely with BoNT/A recognized 2-13 (average 6.

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Lymph node cells (LNC) from SJL (H-2(s)) and BALB/c (H-2(d)) mice primed once with inactivated botulinum neurotoxin type A (BoNT/A) were examined for their T-cell responses to each of 32 synthetic overlapping peptides (19 residues each, L1-L32) that encompass the entire L chain (residues 1-448) of BoNT/A. LNC of SJL gave strong responses to 6 regions on, L2 (residues 15-23), L10/11/12 (127-173), L19 (253-271) and L21 (281-299), and moderate to weak responses to L9 (113-131), L14/15 (183-215) and L27 (365-383). In BALB/c, LNC gave a substantial T-cell response only against peptide L12 (residues 155-173), and responded very weakly to 9 other peptides.

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We have previously reported that botulinum neurotoxin type A (BoNT/A)-specific T-cell responses occur in a majority of patients treated with botulinum neurotoxins (BoNT). In this study, we first determined if T-cell responses against BoNT/A and tetanus toxin (TeNT) differ between cervical dystonia (CD) patients and other movement disorder cases. Secondly, we have examined in CD cases the treatment parameters that may have an effect on the T-cell responses against BoNT/A.

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We investigated in two inbred mouse strains the submolecular recognition of botulinum neurotoxin type A (BoNT/A) by Abs (B cells) and by T lymphocytes. For mapping, we employed a set of overlapping synthetic peptides that encompassed the entire light (L) chain of BoNT/A. After 3 BoNT/A toxoid injections, BALB/c T cells responded in vitro to challenge by peptides L18 (residues 239-257), L23 (309-327), L27 (365-383), L29 (393-411), or L31 (421-439) and more weakly to peptides L3 (29-47), L9/L10 (113-145), L15 (197-215), L17 (225-243), or L26 (351-369).

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Myasthenia gravis (MG) is an autoimmune disease usually associated with autoantibodies (auto-Abs) against nicotinic acetylcholine receptor (AChR). Some MG patients appear negative for anti-AChR Abs (seronegative), and a fraction of these have auto-Abs against muscle-specific kinase. The remaining patients, although displaying MG symptoms, show no detectable auto-Abs.

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We determined the T-cell responses against botulinum neurotoxin type A (BoNT/A) and tetanus toxin (TeNT) of peripheral blood lymphocytes from 95 BoNT-treated patients and 63 non-treated control subjects. The patient group included 80 cervical dystonia and 15 other movement disorder cases. Positive T-cell responses to BoNT/A were detected in 70% of the treated patients, and in only 3% of controls.

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An unanticipated discovery was made while examining genetics of the immune response in patients treated with botulinum neurotoxin (BoNT), which included cervical dystonia (CD) patients. Initial examination of HLA DQA1:DQB1 frequencies revealed an unexpectedly high number of DQA1*0102:DQB1*0604 homozygotes (hz) in the CD patients. We typed the BoNT-treated CD Caucasian subset for HLA-DRB1, DQA1, and DQB1 and succeeded in typing HLA-DRB1, -DQA1, and -DQB1 for 75 of the patients.

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In autoimmune disease, production of disease-causing auto-antibodies (Abs) depends on autoreactive T cells that recognize the epitopes of the pathogenic antigen in the context of MHC class II molecules. It is possible that selective inhibition of an antigen-presenting function of disease-associated MHC alleles could lead to suppression of the disease. Myasthenia gravis (MG) is a disabling neuromuscular disease in which autoimmune responses against acetylcholine receptor (AChR), especially against the alpha chain of AChR, cause a postsynaptic defect.

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The HLA DQA1 and DQB1 alleles were determined on a set of 24 myasthenia gravis patients that had previously been examined for their T-cell proliferative responses to the 18 overlapping peptides representing the extracellular domain of hAChR alpha-chain. Patient responses according to assumed cis or trans haplotypes were significantly higher in most cases relative to normal controls. Comparisons of in vitro peptide-stimulated T-cell responses of patient pairs which had DQA1:DQB1 in common displayed responses in tighter distribution relative to comparisons in which patient pairs did not share the same DQA1:DQB1 haplotype.

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We have investigated the efficacy of the combined use of Alum and inactive Bordetella pertussis (iBP) adjuvants for eliciting anti-peptide antibodies. ICR mice were immunized four times at 3-week intervals with each of 7 free (i.e.

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Unlabelled: Myasthenia gravis (MG) is mostly caused by anti-acetylcholine receptor (AChR) auto-antibodies (Abs). Such Abs are undetectable in 10-15% of MG patients, but many have anti-muscle-specific kinase (MuSK) Abs. We injected recombinant rat-MuSK extracellular domain in H-2(a), H-2(b), H-2(bm12) and H-2(d) mice.

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We have investigated the efficacy of immunization against peptides from predisposing MHC class II molecules in human-compatible adjuvants for ameliorating experimental autoimmune myasthenia gravis (EAMG). C57BL/6 mice were immunized three times with the peptide I-Abetab62-76 in Alum+killed pertussis organisms (PT) prior to two injections with tAChR. The treatment greatly reduced the occurrence and severity of clinical MG relative to controls that received saline/Alum+PT or none.

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It has been indicated that multiple genes, including HLA genes, are collectively involved in the susceptibility to myasthenia gravis (MG). DQB1 alleles represent one of those associated with MG. We have prepared B-cell hybridomas that produce mAbs against peptides corresponding to the tip of the MHC antigen-binding cavity (region 70-90) of alleles DQB1*02, *03, *05 and *06.

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Peripheral blood lymphocytes (PBLs) were isolated from 24 patients with myasthenia gravis of three ethnic groups (Caucasian, African American, and Hispanic) and ten healthy individuals. We determined the in vitro proliferative responses of the PBL samples to each of 18 overlapping synthetic peptides corresponding to the entire main extracellular domain (residues 1-210) of the alpha-subunit of human acetylcholine receptor. The profiles of the T-cell responses (expressed in stimulation index [SI]) to the peptides varied among the 24 patient samples.

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An animal model of myasthenia gravis (MG), termed experimental autoimmune MG (EAMG), can be induced in C57BL/6 (B6, H-2b) mice by immunization with Torpedo californica acetylcholine receptor (tAChR). We have investigated the effect of vaccination with MHC class II peptide I-A beta(b)62-76 on clinical EAMG and on T cell and antibody (Ab) responses against tAChR. B6 mice were vaccinated with the peptide (25 microg/mouse) four times prior to two injections with tAChR.

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