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T Shiohara

Publications and source records attributed to T Shiohara.

At least 37 records · Page 2Linked to original sources
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↗
PubMed1999

Distinct in vivo and in vitro cytokine profiles of draining lymph node cells in acute and chronic phases of contact hypersensitivity: importance of a type 2 cytokine-rich cutaneous milieu for the development of an early-type response in the chronic phase.

Although regional lymph nodes (LN) have been extensively studied as rich sources of effector T cells in contact hypersensitivity (CH), it remains unknown whether T cell responses in the LN reflect those in effector skin sites. We previously showed that repeated elicitation of CH results in a shift in the time course of Ag-specific CH from a delayed-type hypersensitivity response to an early-type response, a reflection of a shift in cutaneous cytokine expression from a type 1 to a type 2 profile. To investigate whether repeated elicitation of CH could also drive T cell development to the type 2 phenotype in the regional draining LN, sequential cytokine gene expression after hapten application was assessed during both the acute and the chronic phase of CH. In the draining LN the shift to type 2 cytokine production was also observed, but more mixed patterns of responses were induced than in the corresponding skin sites. The chronic LN cells (LNC), when stimulated in vitro, produced markedly lower levels of type 1 cytokines and higher levels of type 2 cytokines than the acute LNC. A successful passive transfer of an early-type response by the LNC was only induced in the recipient mice when the skin sites chronically treated with hapten were elicited. These results indicate that an early-type response by regional LNC would take place only in a milieu with sufficient levels of type 2 cytokines.

Acute Disease↗
PubMed1999

An immunohistochemical study of beta1,4-galactosyltransferase in human skin tissue.

An immunohistochemical investigation of beta1,4-galactosyltransferase (beta1,4-GalT) on human skin tissue was performed on formalin-fixed paraffin-embedded sections using a monoclonal antibody, MAb8628, which specifically recognizes a protein moiety of human beta1,4-GalT. Distribution of the galactose beta1,4-N-acetylglucosamine (Gal beta1,4GlcNAc)-R epitope was also detected by staining with Ricinus communis agglutinin (RCA) 120. The beta1,4-GalT was observed to be localized at the perinuclear region of epidermal keratinocytes. The fine localization was also observed at the supranuclear region in the cells of apocrine glands, eccrine ducts and glands. The positive staining with RCA 120 was well colocalized with the cells expressing the beta1,4-GalT. An electron microscopic study revealed that positive signals of beta1,4-GalT definitely reside in the Golgi apparatus. No immunoreactivity was observed in any other intracellular structure or on the cell surface. These findings strongly indicated that the beta1,4-GalT is the major enzyme responsible for the Gal beta1,4GlcNAc-R epitope synthesis in human skin tissue.

Epidermal Cells↗
PubMed1999

Linear IgA bullous dermatosis in a patient with acute lymphocytic leukemia: possible involvement of granulocyte colony-stimulating factor.

We describe a case of linear IgA bullous dermatosis (LABD) in a patient with acute lymphocytic leukemia during treatment with granulocyte colony-stimulating factor (G-CSF). After a drug eruption due to imipenem cilastatin sodium had disappeared, bullous lesions appeared on the trunk. Results of histopathological studies and direct immunofluorescence studies of the lesion were consistent with LABD. Reinstitution of G-CSF after the resolution, however, did not reproduce the bullous eruptions. This suggests that in addition to G-CSF, the presence of precipitating factors that can synergistically enhance or accelerate the outbreak of the disease is required for the development of bullous lesions. Various cytokines, such as interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), endogenously produced from activated lymphocytes during the drug eruption might have provided a favorable milieu for the onset of G-CSF-induced LABD. We suggest that patients with LABD will need special attention with respect to the type of cytokines or combination of cytokines given as therapeutic modalities.

Drug Eruptions↗
PubMed1998

Cellular and molecular dynamics in exercise-induced urticarial vasculitis lesions.

BACKGROUND: Based on the histologic findings of fully developed lesions, leukocytoclastic vasculitis has been regarded as the histologic criterion for differentiating urticarial vasculitis from urticaria. Nevertheless, because the early lesions have not been examined histologically, the key biological events leading to the development of leukocytoclastic vasculitis remain unknown. To address this issue, urticarial vasculitis lesions induced by physical exercise were sequentially examined histologically and immunohistochemically in a patient over the course of 24 hours. Serum levels of various cytokines also were determined in parallel. OBSERVATIONS: At 3 hours after exercise challenge, the number of identifiable mast cells decreased and the first cell type that appeared around the vessels was the eosinophil. The serum tumor necrosis factor alpha level was strikingly increased as compared with that before challenge. Intense expression of E-selectin was also induced at 3 hours. The deposition of eosinophil peroxidase was observed at 3 hours and reached maximum deposition at 10 hours. The eosinophil peroxidase deposits preceded the prominent influx of neutrophils and the subsequent deposits of neutrophil elastase. CONCLUSION: The extracellular deposition of eosinophil granule proteins, in addition to the deposition of immune complexes and a variety of cytokines from the infiltrating cells, appears to be one of the key biological events that determines whether urticarial lesions resolve without causing vasculitis or develop into vasculitis.

Antigen-Antibody Complex↗
PubMed1998

Human herpesvirus 6 infection as a risk factor for the development of severe drug-induced hypersensitivity syndrome.

BACKGROUND: Drug-induced hypersensitivity syndrome is characterized by a severe, potentially fatal, multiorgan hypersensitivity reaction that usually appears after prolonged exposure to certain drugs. Its delayed onset and clinical resemblance to infectious mononucleosis suggest that underlying viral infections may trigger and activate the disease in susceptible individuals receiving these drugs. OBSERVATIONS: A 60-year-old woman developed an itchy, generalized, erythematous, confluent rash on the 39th day of receiving allopurinol therapy. Even after she discontinued treatment with allopurinol, her skin lesions progressed to severe blistering skin eruption. After the patient started oral prednisone therapy, her skin lesions resolved with desquamation. After complete resolution, rechallenge with allopurinol led to the development of an erythematous eruption. Titers of human herpesvirus 6 IgG antibodies dramatically increased with the development of the eruption. The results of a polymerase chain reaction and in situ hybridization indicated the presence of human herpesvirus 6 in the skin lesions, although human herpesvirus 7 DNA was detected only by in situ hybridization. CONCLUSION: Reactivation of human herpesvirus 6, possibly in concert with human herpesvirus 7, can contribute to the development of a severe drug-induced hypersensitivity syndrome.

DNA, Viral↗
PubMed1998

Improvement of lichen nitidus after topical dinitrochlorobenzene application.

Recently, a relationship between immunologic alterations and the development of lichen nitidus (LN) lesions has been described. We treated LN lesions with topical dinitrochlorobenzene (DNCB) application in a patient with peripheral CD4+ T lymphocytopenia. After 4 months, the eruption cleared. We investigated histologically and immunohistochemically biopsy specimens obtained before and after treatment. Our result suggests that local alterations of the pattern of cells and cytokines by topical DNCB application could have contributed to the resolution of the LN lesions.

Administration, Topical↗
PubMed1998

Fixed drug eruption presenting as erythema dyschromicum perstans: a flare without taking any medications.

Fixed drug eruption (FDE) can present as multiple pigmented macules that flare at fixed sites even when the patient has taken no medications. Although this presentation is not characteristic of FDE, it must be borne in mind in order to make a correct diagnosis. We describe such a patient whose condition was initially diagnosed as erythema dyschromicum perstans (EDP). Immunohistochemically intraepidermal T cells were distributed between basal and suprabasal keratinocytes in the lesional skin, a finding suggestive of FDE. A flare occurred not only with exposure to theophylline but also without exposure. A flare has never recurred and pigmented macules faded gradually after avoiding theophylline. On the basis of these findings, we recommend that patients with an EDP-like presentation be examined completely for causes such as drugs before labeling the cutaneous lesions.

Child↗
PubMed1997

Repeated elicitation of contact hypersensitivity induces a shift in cutaneous cytokine milieu from a T helper cell type 1 to a T helper cell type 2 profile.

We previously demonstrated that repeated application of 2,4,6-trinitro-1-chlorobenzene resulted in a site-restricted shift in the time course of Ag-specific hypersensitivity responses from a typical delayed-type to an early-type response. Here we demonstrated that the cutaneous microenvironment at the time of Ag presentation to T cells in the elicitation, but not the induction, phase of contact hypersensitivity is responsible for the shift. To investigate the differences in the cutaneous cytokine milieu between the acute and chronic phases of contact hypersensitivity, sequential cytokine dynamics after 2,4,6-trinitro-1-chlorobenzene application were assessed in the acute vs chronic lesions. In the acute lesions, increased mRNA levels for IFN-gamma and IL-2 were rapidly detected at 1 h and remained elevated at 12 h, while mRNA expression for IL-4 and IL-10 was minimally up-regulated between approximately 12 and 24 h. In chronic lesions, high levels of constitutive expression of IL-4 mRNA were observed and IL-10 mRNA was dramatically up-regulated at 1 approximately 3 h in an Ag-specific fashion, whereas the expression of Th1-type cytokines was markedly reduced. Increased mRNA levels for Th2-type cytokines in the chronic lesions was also reflected at the protein level. These results indicate that repeated elicitation with Ag alters the balance of cytokines released locally, with a shift toward Th2-dominated responses, which would represent the natural evolution processes directed toward reducing a more deleterious Th1 response.

Administration, Cutaneous↗
PubMed1997

Successful treatment of Schamberg's disease with pentoxifylline.

Three patients with Schamberg's disease were treated with pentoxifylline, 300 mg daily for 8 weeks. A significant response was observed within 2 to 3 weeks. One patient had recurrence after discontinuation of this treatment; but promptly responded to resumption of therapy. No adverse effects were noted in any patients. We investigated the expression pattern of adhesion molecules in relation to perivascular accumulation of lymphocytes in specimens obtained before and after treatment with pentoxifylline in these patients. Our results suggest that pentoxifylline exerts its therapeutic effects on Schamberg's disease at the level of T-cell adherence to endothelial cells and keratinocytes.

Adult↗