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Biomedical subjects

T Shiohara

Publications and source records attributed to T Shiohara.

At least 19 recordsLinked to original sources
PubMed2002

Protective and curative effects of topically applied CX-659S, a novel diaminouracil derivative, on chronic picryl chloride-induced contact hypersensitivity responses.

BACKGROUND: CX-659S, a newly discovered anti-inflammatory compound, exerts inhibitory effects against acute contact hypersensitivity responses (CHRs) induced by picryl chloride (PC), oxazolone and dinitrochlorobenzene. The murine model of chronic CHR induced by repeated application of PC is known to mimic many, if not all, events occurring within the lesional skin of patients with atopic dermatitis (AD). OBJECTIVES: To investigate the ability of CX-659S to inhibit PC-induced chronic CHR in mice. METHODS: The protective and curative effects of CX-659S were tested on PC-treated ears of BALB/c mice, and were compared with those of prednisolone. Effects were quantified by measurements of ear thickness, serum IgE and cytokine mRNA expression. RESULTS: Both protectively applied and curatively applied CX-659S significantly inhibited increases in ear thickness and total serum IgE. Inhibition was dose-dependent. Although protectively applied prednisolone showed similar activities to CX-659S against chronic CHR, curatively applied prednisolone did not affect the serum IgE level despite inhibiting increases in ear thickness and inflammatory cell infiltration. Consistent with these results, CX-659S reduced mRNA expression of interleukin (IL)-4 and IL-10 but not of interferon (IFN)-gamma, whereas prednisolone inhibited not only mRNA expression of IL-4 and IL-10 but also that of IFN-gamma in the ear lesion. In contrast to prednisolone, CX-659S did not show any side-effect such as atrophy, alopecia or telangiectasia. CONCLUSIONS: CX-659S is the first promising compound having inhibitory activities against chronic CHR accompanied by a diminishing effect on elevated serum IgE, without any other side-effect. Therefore, CX-659S may be a promising candidate for management of patients with recurring AD who require long-term therapy.

Administration, Topical↗
PubMed2002

Preferential expression of alphaEbeta7 integrin (CD103) on CD8+ T cells in the psoriatic epidermis: regulation by interleukins 4 and 12 and transforming growth factor-beta.

BACKGROUND: Intraepidermal T lymphocytes are a critical element for sustaining the lesional pathology of psoriasis. Integrin alphaEbeta7 (CD103), a ligand for E-cadherin, may play a role in the localization of pathogenic T cells within the epidermis of psoriatic lesions. However, little information is available regarding alphaEbeta7 expression on intraepidermal T cells in psoriasis. OBJECTIVES: To examine alphaEbeta7 expression on intraepidermal T cells in psoriatic lesions and the regulation of alphaEbeta7 expression on T cells in response to cytokines. METHODS: T-cell expression of alphaEbeta7 was examined by immunohistochemistry and flow cytometry. In vitro regulation of alphaEbeta7 expression on CD4+ or CD8+ T cells purified from peripheral blood of healthy donors was also examined. RESULTS: Immunohistochemical staining revealed expression of alphaEbeta7 on a greater proportion of epidermal T cells than dermal T cells. Nearly 30% of intraepidermal CD4+ T cells were found to express alphaEbeta7 on flow cytometry, whereas more than 80% of intraepidermal CD8+ T cells expressed this integrin. In contrast, few T cells expressed alphaEbeta7 in the peripheral blood of psoriatic patients. The in vitro culture experiment confirmed that alphaEbeta7 was preferentially expressed on CD8+ T cells after stimulation with anti-CD3 monoclonal antibodies. Addition of transforming growth factor-beta and interleukin-4 upregulated alphaEbeta7 expression on T cells, whereas interleukin 12 downregulated this. Furthermore, alphaEbeta7 expression on established memory CD8+ T cells was not so reversible as that on CD4+ T cells. CONCLUSIONS: Preferential and stable expression of alphaEbeta7 on CD8+ T cells may be involved in the lesional pathology of psoriasis.

Adult↗
PubMed2001

Immunohistochemical detection of skin-homing T cells expressing fucosyltransferase VII (Fuc-TVII) in vitro and in situ.

Although expression of cutaneous lymphocyte-associated antigen (CLA) is thought to be a specific marker of skin "homing" T cells, it has become clear that CLA is a good marker for high levels of fucosyltransferase VII (Fuc-TVII) activity but does not necessarily represent the epitope required for binding to E-selectin (Wagers et al, 1996, 1997). Therefore, expression of Fuc-TVII is an attractive candidate for identifying skin "homing" T cells. However, analyses of Fuc-TVII expression in human T cells have been performed only at the mRNA level (Nakayama et al, 2000) because of the lack of mAB: In this study Fuc-TVII was for the first time visualized in individual cells by using a novel mAb that we developed. Double immunofluorescence and immunohistochemistry demonstrated the coexpression of Fuc-TVII and CLA in cell lines in which Fuc-TVII mRNA was shown to be expressed at high levels: whereas CLA expression was seen in the cell membrane, Fuc-TVII was identified in a supra- or perinuclear location. Cytoplasmic Fuc-TVII expression was also detectable in both CD4(+) and CD8(+) T cells purified from peripheral blood. Fuc-TVII was also expressed at high levels in many CLA(+) T cells infiltrating the skin. In these peripheral T cells, unlike in cell lines, cytoplasmic expression of Fuc-TVII was not always associated with surface CLA expression. This mAb would serve as a valuable tool for selectively identifying a novel subset of skin "homing" T cells that are not detected by the conventional method because of the lack of CLA expression.

Antibodies, Monoclonal↗
PubMed2001

Skin-homing interleukin-4 and -13-producing cells contribute to bullous pemphigoid: remission of disease is associated with increased frequency of interleukin-10-producing cells.

Although evidence is accumulating that type 2 cytokines play a part in the pathogenesis of bullous pemphigoid, little information is available concerning characterization of the cellular source of these cytokines involved in the pathogenesis of bullous pemphigoid. By using multiparameter flow cytometry, we investigated T cells capable of producing interleukin-2, -4, -10, and -13, interferon-gamma, and tumor necrosis factor-alpha and their correlated expression of skin-homing receptor (cutaneous lymphocyte-associated antigen) in peripheral blood and skin blister of patients with bullous pemphigoid. In peripheral blood of bullous pemphigoid patients, significantly increased frequencies of interleukin-4- and interleukin-13-producing cells were found as compared with those of healthy controls, and the majority of these type 2 cells was found in the cutaneous lymphocyte-associated antigen-positive population. The frequency of interferon-gamma-producing cells was also increased as compared with healthy subjects; however, the majority of this subset was found in the cutaneous lymphocyte-associated antigen-negative population. In the skin blister, the frequencies of interleukin-13- and interleukin-4-producing cells were much higher than those in the peripheral blood of bullous pemphigoid, whereas that of interferon-gamma producing cells was significantly lower. Furthermore, in bullous pemphigoid patients after therapy with systemic corticosteroids, the frequency of cutaneous lymphocyte-associated antigen-positive, but not cutaneous lymphocyte-associated antigen-negative, interleukin-13-producing cells was significantly decreased accompanied by an increased frequency of interleukin-10-producing cells, which was associated with clinical improvement. Thus, our results suggest that bullous pemphigoid is a unique organ-specific autoimmune disease characterized by an expansion of skin-homing interleukin-13-producing cells. In addition, corticosteroids may control such type 2 biased inflammatory responses in bullous pemphigoid by promoting the expansion of interleukin-10-producing cells.

Adrenal Cortex Hormones↗
PubMed2001

The cytokine profile in a transient variant of angioedema with eosinophilia.

Episodic angioedema with eosinophilia is characterized by recurrent angioedema, fever and weight gain with a remarkable eosinophilia. A transient type, predominantly reported in Japan, in which the disease is limited to a single attack, is usually less severe than the episodic type described in the U.S.A. and Europe, and provides an ideal disease model in which to study the mechanisms for resolution of eosinophilic inflammation. The aim of this study was to evaluate the relationship between cytokine responses and clinical course in three patients with the transient type. Serum levels of interleukin (IL) -5 were only marginally elevated even during an attack, unlike those in reported cases of the episodic type. Significant elevations in granulocyte-macrophage colony-stimulating factor levels were also noted during an attack in two cases in which it was measured. A dramatic increase in tumor necrosis factor (TNF) -alpha levels was subsequently observed in relation to resolution of clinical symptoms. No major changes in the serum levels of soluble Fas and soluble Fas ligand were found throughout the course. These results suggest that relatively lower levels of IL-5 and a subsequent increase in TNF-alpha levels are characteristic features of the transient type. The differences in clinical symptoms and course observed between the two types may be partly explained by the differences in the cytokine profiles.

Adult↗
PubMed2001

Development and characterization of a monoclonal antibody specific for fucosyltransferase VII (Fuc-TVII): discordant expression of CLA and Fuc-TVII in peripheral CD4+ and CD8+ T cells.

Although cutaneous lymphocyte-associated antigen (CLA) is thought to be specifically expressed on skin "homing" T cells, it has become clear that CLA is not directly involved in binding to E-selectin but represents an excellent marker for high levels of fucosyltransferase VII (Fuc-TVII): Fuc-TVII can regulate the ability of T cells to migrate into the skin by generating a binding site for E-selectin. In this study, by using a novel monoclonal antibody for Fuc-TVII, we investigated whether expression of Fuc-TVII could be selectively detected in various CLA+ cell lines and peripheral blood T cells. Fuc-TVII was readily detected in the cytoplasm, but not in the membrane, of CLA+ cell lines. Cytoplasmic Fuc-TVII expression was also detectable in both CD4+ and CD8+ T cells purified from peripheral blood mononuclear cells. Nevertheless, there were significant numbers of CLA-expressing CD4+ or CD8+ T cells that did not coexpress Fuc-TVII, and vice versa: either the CD4+ or the CD8+ T cell population consisted of a variable ratio of CLA+ Fuc-TVII+, CLA+ Fuc-TVII-, and CLA- Fuc-TVII+ cells; and CLA+ Fuc-TVII- cells were the most abundantly identifiable phenotype in peripheral blood CD4+ and CD8+ T cells. Thus, according to their expression pattern, skin "homing" T cells can be subdivided into at least three populations, CLA+ Fuc-TVII+, CLA+ Fuc-TVII-, and CLA- Fuc-TVII+ cells. Our study provides convincing evidence that skin "homing" T cells are phenotypically heterogenous and that Fuc-TVII expression, in combination with CLA expression, is a useful phenotypic marker for identifying skin "homing" T cells in mixed cell populations.

Antibodies, Monoclonal↗
PubMed2001

Superficial lymphangitis with interface dermatitis occurring shortly after a minor injury: possible involvement of a bacterial infection and contact allergens.

BACKGROUND: Linear supralymphatic eruptions with epidermal involvement have rarely been reported. OBJECTIVE: A search was made for apparent anatomical reasons and for external factors to explain the unique distribution pattern and clinical course in three cases in which the linear lesions occurred shortly after a minor injury. METHODS: Efforts to search for its etiology include careful outlining of the localization, bacterial culture from the site of traumatic injury, patch tests, and skin biopsies. RESULTS: Linear lesions developed along superficial lymphatic vessels and the presence of eczematous conditions around the injured sites and isolation of Staphylococcus aureus from the site were observed concomitantly. The histopathological findings showed interface dermatitis. CONCLUSION: Our cases provide a unique example of the combined effects of a bacterial infection and contact allergens in the development of the linear supralymphatic eruptions.

Adult↗
PubMed2000

Mental stress and physical exercise increase platelet-dependent thrombin generation.

Thrombin generation is an important factor in the pathogenesis of thrombogenic disorders and acute coronary syndromes. Increase in mental stress has been associated with the initiation of the acute coronary syndromes, but the exact mechanism is not known. The present study examined the effects of physical exercise and mental stress on platelet-dependent thrombin generation. Twelve healthy men (mean age 34.2 +/- 2.4 years) underwent a treadmill exercise test and a mental stress test by performing mental arithmetic. Platelet-dependent thrombin generation and plasma concentrations of catecholamines, thrombin-antithrombin III complex (TAT), plasmin-alpha2 plasmin inhibitor complex (PIC), and plasminogen activator inhibitor-1 (PAI-1) were measured before, immediately after, and at 10 and 30 min after stress. Thrombin generation increased significantly immediately after exercise, followed by rapid normalization. Mental stress caused a significant increase in thrombin generation 10 min after stress. While plasma concentrations of epinephrine, norepinephrine, and dopamine were elevated immediately after exercise, and rapidly returned to baseline, only plasma norepinephrine increased immediately after mental stress. TAT and PIC concentrations did increase immediately after exercise; however, PAI-1 remained unchanged. The increase in thrombin generation with exercise and mental stress was unaffected by treatment with 81 mg/day of aspirin of 7 days. However, it was inhibited by a single oral 40-mg dose of metoprolol. Both exercise and mental stress cause an increase in platelet-dependent thrombin generation, which was suppressed by beta-blocker therapy, but not by aspirin.

Adrenergic beta-Antagonists↗
PubMed2000

Virus-induced immune dysregulation as a triggering factor for the development of drug rashes and autoimmune diseases: with emphasis on EB virus, human herpesvirus 6 and hepatitis C virus.

There are a considerable amount of empirical and theoretic medical literature regarding the possible role of viruses in the development of drug rashes and autoimmune diseases: under these conditions, interactions of viruses with the immune system would serve as an accelerating factor of disease pathogenesis. Recent reports have provided evidence to indicate that immune responses against infections with Epstein Barr (EB) virus and human herpesvirus 6 (HHV-6), which are lymphotropic members of the herpes virus group, not only aid the direct elimination of the virus but also contribute to a favorable milieu for the initiation or acceleration of drug rashes. Viruses that can persist for the lifetime of the host despite strong immune responses against them, such as EB virus and hepatitis C virus (HCV), would be also relevant to the pathogenesis of autoimmune diseases. HCV has been reportedly associated with a wide variety of dermatoses that, in common, show histologically the lichenoid tissue reaction. Although porokeratosis that manifests lichenoid histopathological features had long been regarded as being associated with immunosuppression, we found that HCV could act as trigger for the development of porokeratosis during states of immunosuppression. Thus, the main purpose of this review is to describe recent work on the etiology of drug rashes and autoimmune disease with special reference to viral infections.

Autoimmune Diseases↗
PubMed2000

Current understanding of cytomegalovirus infection in immunocompetent individuals.

Human cytomegalovirus (CMV) is a member of the herpes family of viruses. After primary infection, it undergoes latency/persistence. Significant progress has been made in the last few years in detecting CMV. The most available approach to the diagnosis of CMV infection is the direct detection of CMV antigen in nuclei of peripheral blood leukocytes, an assay known as pp65 direct antigenemia test. CMV infection is well controlled in the immunocompetent hosts; however, there are various immunological changes in immune function during and after recovery from CMV infections. Characteristic changes in lymphocyte subsets occur during CMV infection, mainly involving expansion and activation of CD8+ T lymphocytes and NK cells. On the other hand, CMV has an array of immune escape strategies for establishing a life long latent state: CMV inhibits major histocompatibility complex (MHC) class I expression within infected cells and impairs IFN-gamma-induced MHC class II-dependent antigen presentation by macrophages; it can also encode proteins that can interfere with the presentation of viral peptide antigens to T cells. While cutaneous manifestations of CMV seen in immunocompromised patients have been extensively reported, those in adult immunocompetent individuals have received relatively little attention: in this setting the primary CMV infection appears as CMV mononucleosis. At the time of occurrence of the mononucleosis syndrome, a variety of extracutaneous and cutaneous manifestations occur. These clinical symptoms are not the direct consequence of proliferation of CMV in given tissues but indicative of the immunological response toward CMV. The incidence of the appearance of eruptions in CMV mononucleosis is variable. Certain drugs given in the early stage of this disease play an important role in the development of eruption, just as with the ampicillin rashes in the Epstein-Barr virus mononucleosis. Although the mechanism by which drugs trigger the development of rashes in patients with CMV mononucleosis is unknown, it is assumed that CMV is likely to be a potential amplifier of drug rashes induced by activation of drug-specific T cells. By improving methods for detection of CMV, we can recognize that many types of eruptions other than CMV mononucleosis could be induced by primary infection or reactivation of CMV.

Acute Disease↗
PubMed2000

Increased circulating skin-homing cutaneous lymphocyte-associated antigen (CLA)+ type 2 cytokine-producing cells, and decreased CLA+ type 1 cytokine-producing cells in atopic dermatitis.

BACKGROUND: Skin-homing T cells are characterized by expression of cutaneous lymphocyte-associated antigen (CLA). Few data are available on the frequency of circulating CLA+ cytokine-producing T cells in atopic dermatitis (AD) patients. OBJECTIVES: We aimed to investigate cytokine synthesis capability vs. CLA expression in phorbol myristate acetate and ionomycin-stimulated, secretion-inhibited peripheral blood T cells of AD patients compared with healthy subjects and psoriatic patients. METHODS: Multiparameter flow cytometry was used. RESULTS: The expression of CLA among CD4+ T cells was significantly elevated in AD patients compared with healthy subjects and psoriatic patients, whereas there was no significant difference between each group in CLA expression among CD8+ T cells. The frequency of interleukin (IL)-4- and IL-13-producing cells in AD patients was significantly higher than in healthy subjects (in both CD4+ and CD8+ T-cell subsets) and psoriatic patients (in CD4+ T cells). In contrast, the frequency of interferon (IFN)-gamma-producing cells was significantly reduced in AD patients, among both CD4+ and CD8+ T cells, compared with healthy subjects and psoriatic patients. Moreover, in AD patients, the frequency of IL-4- and IL-13-producing cells was remarkably increased among the CLA+ subset (in both CD4+ and CD8+ T cells), whereas the frequency of IFN-gamma-producing cells was decreased in the CLA+ subset (in CD4+, but not in CD8+ T cells). CONCLUSIONS: These results provide evidence for the expansion of skin-homing type 2 cytokine-secreting T cells, associated with a reduction in skin-homing type 1 cytokine-producing T cells, in peripheral blood of AD patients.

Adult↗
PubMed2000

Expression of cutaneous lymphocyte-associated antigen regulated by a set of glycosyltransferases in human T cells: involvement of alpha1, 3-fucosyltransferase VII and beta1,4-galactosyltransferase I.

Cutaneous lymphocyte-associated antigen (CLA), which plays a key part in skin homing of human CD4+ memory T cells via CLA/E-selectin binding, is upregulated by IL-12 and downregulated by IL-4. Although alpha1,3-fucosyltransferase VII is essential for synthesis of the CLA carbohydrate epitope, little is known about how the CLA expression is regulated by a number of glycosyltransferases. A 6 wk long-term culture for the in vitro differentiation of naïve Th cells to memory Th1 cells was employed. By repeated activation in the presence of IL-12, naïve T cells differentiated into memory Th1 cells, resulting in the upregulation of CLA expression. The switching of cytokine from IL-12 to IL-4 at three cycles resulted in a marked downregulation of CLA. The transcript levels of 16 glycosyltransferases and P-selectin glycoprotein ligand-1, all considered to be potentially involved in CLA synthesis, were determined after each cycle. The level of CLA expression was well correlated with the amounts of alpha1,3-fucosyltransferase VII and beta1,4-galactosyltransferase I. Both were upregulated by IL-12 and downregulated by IL-4. In particular, alpha1,3-fucosyltransferase VII levels decreased markedly in the presence of IL-4. P-selectin glycoprotein ligand-1 and Core 2 beta1, 6-N-acetylglucosaminyltransferase were progressively up-regulated by repeated IL-12 stimulation, but they were not downregulated by IL-4. The transcript levels of some genes examined were constitutive without any correlation to CLA expression. These results suggest that the level of CLA expression is determined by alpha1, 3-fucosyltransferase VII and beta1,4-galactosyltransferase I, the other enzymes merely participating in the synthesis of CLA. In peripheral blood mononuclear cells, IL-12 and IL-4 profoundly upregulated and downregulated the alpha1,3-fucosyltransferase VII transcripts, respectively, but not the beta1,4-galactosyltransferase I ones, within only 2 h of in vitro culture. This suggested that alpha1,3-fucosyltransferase VII is transcriptionally regulated directly by IL-12 and IL-4.

Antigens, Differentiation, T-Lymphocyte↗
PubMed2000

Photo-accentuated eruption and vascular deposits of immunoglobulin A associated with hepatitis A virus infection.

Skin rash associated with hepatitis A virus infection has rarely been reported. We describe a patient with hepatitis A virus infection who presented a rubelliform rash markedly accentuated in sun-exposed areas; direct immunofluorescence studies of the lesion revealed immunoglobulin (Ig) A deposition on the endothelial cells in the upper dermis. Oral rechallenge tests of the previously administered drugs failed to reproduce the eruption. The preferential setting of immune complexes containing IgA at sites of sun exposure and sunlight as a triggering factor might have been responsible for the development of the eruption in this patient. Eruptions associated with hepatitis A virus infections may be more frequent than commonly thought. Because of difficulty to exclude the possibility of drug eruptions, these cases might have been overlooked. In patients with such a disorder, a careful clinical workup such as IgM antibodies for hepatitis A virus at diagnosis and during follow-up is especially recommended.

Adult↗
PubMed2000

Pemphigus foliaceus induced by exposure to sunlight. Report of a case and analysis of photochallenge-induced lesions.

BACKGROUND: Although there are many reports on photo-induced pemphigus, careful analysis in the development of acantholytic blister have rarely been performed in the lesions induced by photochallenge. OBJECTIVE: The study was intended to elucidate the mechanisms by which ultraviolet light (UV) radiation causes the skin lesions of pemphigus foliaceus. METHODS: Photochallenge-induced lesions were examined histologically and immunohistochemically over the time course with three biopsy specimens. Neutrophil adhesion assay was performed using the specimens prepared from the photochallenged lesions as substrates. RESULTS: A small number of neutrophils were seen at 5 h after photochallenge in the dermis and epidermis, and slight acantholysis was detected at 72 h. In neutrophil adhesion assay, greater numbers of neutrophils adhered to the upper epidermis of the skin obtained at 5 h after challenge. CONCLUSIONS: Our results suggest that both enhanced binding of autoantibodies to the epidermis after UV radiation and preferential adhesion of neutrophils to the UV-irradiated epidermis contribute to the development of acantholysis in photo- induced pemphigus foliaceus. Intercellular adhesion molecule-1 (ICAM-1) expression on keratinocytes is not primarily responsible for the epidermal migration of neutrophils.

Cell Adhesion↗