Publications by authors named "Hiroko Nakashima"

The complex and coordinated regulation of flowering has high ecological and agricultural significance. The maturity locus E1 has a large impact on flowering time in soybean, but the molecular basis for the E1 locus is largely unknown. Through positional cloning, we delimited the E1 locus to a 17.

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We report a patient with herpetiform pemphigus who was negative for autoantibodies to desmoglein (Dsg)1 or 3. He had erythemas with vesicles lining the margins on the trunk and extremities. Histopathology revealed intraepidermal blister with prominent eosinophil infiltration.

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Delineating the relative contributions of B lymphocytes during the course of autoimmune disease has been difficult. Therefore, the effects of depleting all mature B cells using a potent CD20 mAb, or of depleting circulating and marginal zone B cells using a ligand-blocking CD22 mAb, were compared in NZB/W F(1) mice, a model for human systemic lupus erythematosus. Single low-dose mAb treatments depleted B cells efficiently in both NZB/W F(1) and C57BL/6 mice.

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B cells play critical roles in the pathogenesis of lupus. To examine the influence of B cells on disease pathogenesis in a murine lupus model, New Zealand Black and New Zealand White F(1) hybrid (NZB/W) mice were generated that were deficient for CD19 (CD19(-/-) NZB/W mice), a B cell-specific cell surface molecule that is essential for optimal B cell signal transduction. The emergence of anti-nuclear Abs was significantly delayed in CD19(-/-) NZB/W mice compared with wild type NZB/W mice.

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Although contact hypersensitivity (CHS) has been considered a prototype of T cell-mediated immune reactions, recently a significant contribution of regulatory B cell subsets in the suppression of CHS has been demonstrated. CD22, one of the sialic acid-binding immunoglobulin-like lectins, is a B cell-specific molecule that negatively regulates BCR signaling. To clarify the roles of B cells in CHS, CHS in CD22(-/-) mice was investigated.

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CD19 is a B-cell transmembrane molecule that is critical for B-cell activation. CD19 serves as a scaffold protein for key signal transduction molecules including Lyn, PI3K, and Vav, by providing docking sites for these molecules via phosphorylation of CD19-Y(513), CD19-Y(482), and CD19-Y(391). We investigated the process of CD19 tyrosine phophorylation during B-cell activation using Ab specific for each of these phosphorylated tyrosines.

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Prominent eosinophil infiltration is a characteristic of some forms of vasculitis, such as Churg-Strauss syndrome, also known as allergic granulomatous vasculitis. In the current study, we established a mouse model of cutaneous eosinophilic vasculitis by the cutaneous reverse passive Arthus reaction using IgE injection instead of IgG. Wild-type C57BL/6 mice were injected with IgE anti-trinitrophenyl antibodies, followed immediately by intravenous administration of trinitrophenyl bovine serum albumin.

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Background: Bullous pemphigoid (BP) is a subepidermal blistering disease characterized by autoantibodies against the hemidesmosomal proteins, BP180 and BP230. NC16A, a non-collagenous stretch of the BP180 ectodomain is the primary target of pathogenic IgG antibodies. Whereas IgG anti-BP180 autoantibodies play a primary role in the pathogenesis, there is a growing number of data regarding the potential pathogenic roles of IgE class autoantibodies in BP.

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The control of the stem cell compartment in epidermis is closely linked to the regulation of keratinocyte proliferation and differentiation. Beta1 integrins are expressed 2-fold higher by stem cells than transit-amplifying cells. Signaling from these beta1 integrins is critical for the regulation of the epidermal stem cell compartment.

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Contact hypersensitivity (CHS) is a cutaneous immune reaction mediated mainly by antigen-specific effector T cells and is regarded as a model for Th1/Tc1-mediated inflammation. However, recent reports have suggested pivotal roles of B cells in CHS. CD19 serves as a positive B-cell response regulator that defines signaling thresholds critical for B-cell responses.

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We report the case of a 55-year-old female with bullous pemphigoid (BP) who was positive for anti-BP180 and anti-laminin 5 antibodies after development of graft-vs-host disease (GVHD) caused by a bone marrow transplant. She had tense blisters on her trunk and extremities. Histologic examination showed a subepidermal blister and marked lymphocytic infiltration, especially eosinophils.

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Although anti-Fcgamma receptor antibodies (Abs) are detected in various autoimmune diseases, there have been no studies about the anti-Fcgamma receptor Abs in alopecia areata (AA). To detect the anti-Fcgamma receptor Abs in patients with AA and their clinical correlations, Serum samples from 72 patients with AA and 23 normal controls were examined by enzyme-linked immunosorbent assay assessing anti-Fcgamma receptor Ab levels. Anti-Fcgamma receptor I Abs were significantly frequently detected in patients with AA compared with normal controls.

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Necrolytic migratory erythema (NME) is an uncommon inflammatory dermatosis with a distinctive clinical and histological appearance. It shows irregular erythema, bullae, erosion, crusts and pigmentation. While it is typically associated with glucagonoma, some cases of NME without glucagonoma have been reported.

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Cell surface molecules on lymphocytes positively or negatively modulate the Ag receptor signaling, and thus regulate the fate of the cell. CD22 is a B cell-specific cell surface protein that contains multiple ITIMs in the cytoplasmic tail, and critically regulates B cell activation and survival. CD22 regulation on B cell signaling is complex because CD22 can have both positive and negative roles in various contexts.

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