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T Bieber

Publications and source records attributed to T Bieber.

At least 19 recordsLinked to original sources

[Advances in the pathogenesis of atopic dermatitis].

The incidence of atopic dermatitis (AD) is noticeably increasing in industrialized countries. New insights into the pathogenesis of this disease are mirrored by a changed terminology suggested by the World Allergy Organization: a distinction between a so-called atopic and non-atopic dermatitis. The pathogenesis of the AD, which this article concentrates on, is highly complex. Genetic and environmental factors play a pivotal role in triggering AD. The complex pattern of cytokines and chemokines, reflecting a deviated immune response in AD patients, is a focus of research, as are the involvement of various cells and the epidermal barrier. Research concerning T cells with regulatory features as well as IgE-mediated autoreactivity will soon give insight into the defective tolerance of atopic patients and might possibly lead to new concepts in the management of the disease.

Adult↗

Type I interferon-associated skin recruitment of CXCR3+ lymphocytes in dermatomyositis.

BACKGROUND: Dermatomyositis (DM) is an autoimmune disease of unknown origin affecting skin and muscles. Infiltrating autoreactive T lymphocytes are thought to play an important pathogenetic role, but it is unclear which mechanisms are involved in the recruitment of these cells. Recent studies provided evidence that a type I interferon (IFN)-driven immune response, including the recruitment of T cells via IP10/CXCR3 interactions, might be important for the generation of skin lesions of cutaneous lupus erythematosus (CLE), an autoimmune disease that shares some clinical and histopathological features with DM. We hypothesized that a similar mechanism might also be involved in the pathogenesis of DM skin lesions. METHODS: Skin biopsies of 23 donors (11 DM, 5 healthy controls, 7 CLE controls) were analysed by immunohistochemistry using monoclonal antibodies against CD3, CD4, CD8, CD20, CD68, CD123, the chemokine receptor CXCR3 and its ligand IP10/CXCL10, and the myxovirus-resistance protein A (MxA)-protein, which is a specific marker for type I IFNs. RESULTS: We detected strong expression of the MxA protein in all DM skin biopsies, indicating involvement of type I IFNs. Expression of MxA was closely associated with expression of the interferon-inducible protein IP10/CXCL10 and the recruitment of CXCR3+ lymphocytes. Plasmacytoid dendritic cells appear to be an important source of type I IFNs in DM. DISCUSSION: Our results support the hypothesis that lesional type I IFN signalling, induction of IP10 expression, and recruitment of potentially autoreactive T cells via IP10/CXCR3 interaction are involved in the pathogenesis of DM skin lesions.

Adult↗

Comparative analysis of nasal and oral mucosa dendritic cells.

BACKGROUND: Mucosal dendritic cells (DC) play a crucial role in tolerance induction as seen in mucosal immunotherapy of atopic diseases. Nevertheless little is known about the phenotypical differences of oral and nasal mucosal DC (nmDC). Recently, we could show that oral mucosal myeloid CD1a(+) DC (omDC) differ from their skin counterparts especially by the expression of high affinity receptor for immunoglobulin E (IgE; FcepsilonRI). However, expression pattern of FcepsilonRI and phenotypical characteristics of CD1a(+) nmDC have not been elucidated in detailed yet. METHODS: We performed detailed phenotypical comparison of nmDC and omDC of atopic and nonatopic individuals. RESULTS: As reported for omDC, FcepsilonRI on nmDC of atopic donors was elevated and mostly occupied by IgE while FcepsilonRI was present only in low amounts on nmDC of nonatopic donors. Nevertheless, the highest FcepsilonRI expression has been observed on omDC. Furthermore, significant amounts of costimulatory molecules CD40, CD80 and CD86 could be detected on nmDC that expressed more CD80 compared with omDC. Moreover, nmDC displayed less major histocompatability complex (MHC) class I and II molecules than omDC. In addition, nmDC expressed more C-type lectins CD205, CD206 as well as myeloid marker CD11b while omDC displayed increased expression of CD207 and lipopolysaccharide (LPS) receptor CD14. CONCLUSION: Together these data imply that nmDC phenotypical differ from omDC which might result in diverse functional properties and might be of relevance for selecting routes for immunotherapy of atopic diseases. Moreover these data provide a basis for further studies investigating immunological mechanisms underlying mucosal immunotherapy.

Adult↗

Onset of pruritus relief with pimecrolimus cream 1% in adult patients with atopic dermatitis: a randomized trial.

BACKGROUND: Pimecrolimus cream 1% (Elidel, Novartis Pharmaceuticals AG) effectively improves/relieves pruritus associated with atopic dermatitis (AD), but few data are available regarding the timing of relief. The purpose of this study was to investigate the timing of pruritus relief produced with pimecrolimus in adults with mild/moderate AD and moderate/severe pruritus. METHODS: Patients were randomized to 7 days of treatment with pimecrolimus (n = 100) or vehicle (n = 98). Pruritus severity was assessed daily on a 4-point scale (0 = absent, 3 = severe), reflecting the previous 24 h experience. Patients who completed this core study were eligible to enter a voluntary 5-week, open-label extension study. RESULTS: A significant effect was noted within 48 h of treatment, with pruritus improving in 56% of pimecrolimus-treated patients and 34% of vehicle-treated patients (P = 0.003). Pruritus relief was maintained during the remainder of the core and extension phases, and was accompanied by an improvement in the Investigator's Global Assessment score. CONCLUSION: Pimecrolimus cream 1% significantly reduced pruritus within 48 h.

Administration, Topical↗

Themes in allergy.

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Developed Countries↗

Diagnosis and treatment of atopic dermatitis in children and adults: European Academy of Allergology and Clinical Immunology/American Academy of Allergy, Asthma and Immunology/PRACTALL Consensus Report.

There are remarkable differences in the diagnostic and therapeutic management of atopic dermatitis practiced by dermatologists and pediatricians in different countries. Therefore, the European Academy of Allergy and Clinical Immunology and the American Academy of Allergy, Asthma and Immunology nominated expert teams who were given the task of finding a consensus to serve as a guideline for clinical practice in Europe as well as in North America. The consensus report is part of the PRACTALL initiative, which is endorsed by both academies.

Adult↗

Recent highlights in the pathophysiology of atopic eczema.

Atopic eczema (AE) belongs to the group of atopic diseases that have become increasingly prevalent over the last decades. The pathophysiology of AE has long remained enigmatic, but much scientific effort has been invested in elucidating the genetic background and the immunological mechanisms underlying AE, leading to a better understanding of this complex disease and to new therapeutic strategies. This review provides an update on the scientific progress that has been achieved in clarifying the pathophysiological mechanisms of AE.

Dermatitis, Atopic↗

Circulating clonal CLA(+) and CD4(+) T cells in Sezary syndrome express the skin-homing chemokine receptors CCR4 and CCR10 as well as the lymph node-homing chemokine receptor CCR7.

BACKGROUND: Adhesion molecules and chemokine receptors are involved in tissue-specific homing of T cells to the skin and play an important role in the pathophysiology of cutaneous lymphoma. It has recently been reported that the chemokine CCL27 expressed by keratinocytes attracts lymphocytes bearing the chemokine receptor CCR10. OBJECTIVES: To investigate the expression of CCR4, CCR7 and CCR10 on skin-homing CLA(+) and CD4(+) T cells in the peripheral blood of patients with Sezary syndrome (SS), a rare leukaemic variant of cutaneous T-cell lymphoma. METHODS: Lymphocytes from five patients with SS, six patients with mycosis fungoides and four healthy volunteers were isolated and analysed using flow cytometry. Additionally, the T-cell receptor (TCR)-Vbeta CDR3 regions were cloned and sequenced in two patients. RESULTS: We found that CCR4 is expressed on almost all CLA(+) and CD4(+) memory T cells. Using monoclonal antibodies specific for single TCR-Vbeta chains we identified malignant T cells in four patients with SS. Importantly, we found that most but not all malignant Sezary cells expressed the skin-homing chemokine receptor CCR10. Additionally, we found that a significant proportion of these cells also expressed the lymph node-homing chemokine receptor CCR7. CONCLUSIONS: Our results support the concept that chemokine receptors play an important role in the pathophysiology of SS and suggest that the malignant clone may represent an expansion of skin-homing cutaneous 'central' memory T cells in the peripheral blood of these patients.

Adult↗

Efficacy and safety of methotrexate in recalcitrant cutaneous lupus erythematosus: results of a retrospective study in 43 patients.

BACKGROUND: The therapy of cutaneous lupus erythematosus (CLE) is often challenging, especially in patients resistant to topical treatment and established first-line systemic drugs such as antimalarials. Systemic corticosteroids are effective, but their use is limited due to well-known side-effects, especially in long-term treatment. In recent years several other immunosuppressive agents have been successfully applied in CLE. However, there are no large studies or explicit guidelines on the use of these drugs in CLE. OBJECTIVES: To perform a retrospective investigation of the efficacy of low-dose methotrexate (MTX) in the treatment of CLE. METHODS: One hundred and thirty-nine patients with CLE were seen at our department between 2001 and 2003, of whom 43 patients required low-dose MTX. All had histologically confirmed CLE lesions. Clinical data including disease activity, additional treatment, laboratory parameters and side-effects were recorded carefully at the time of presentation. Statistical analyses were performed by paired nonparametric Wilcoxon test and Student's t-test using SPSS 11 software. RESULTS: MTX led to a highly significant (P < 0.01) decline in disease activity. An improvement of the cutaneous lesions was recorded in nearly all patients treated with MTX (42 of 43; 98%). Severe side-effects necessitating discontinuation of MTX treatment were recorded in seven patients (16%), which quickly resolved when MTX was discontinued. Life-threatening complications were not observed. Intravenous application was tolerated better than oral administration. Interestingly, we observed a significant increase in circulating lymphocyte numbers in patients with lymphopenia (< 1.0 x 10(9) cells L(-1)) prior to MTX treatment. CONCLUSIONS: Our study supports earlier findings reporting the efficacy of low-dose MTX in CLE lesions, particularly in recalcitrant clinical courses. MTX treatment appears to be safe if patients are carefully selected and monitored, with particular attention to side-effects and contraindications.

Adult↗

A multicentre, randomized, double-blind, controlled study of long-term treatment with 0.1% tacrolimus ointment in adults with moderate to severe atopic dermatitis.

BACKGROUND: Atopic dermatis (AD) is a chronic disease that often requires long-term treatment. Topical corticosteroids are the usual therapy for patients with AD, but prolonged usage can result in skin atrophy and other side-effects. OBJECTIVES: In a randomized, double-blind, comparative study, to compare the efficacy and safety of a 6-month treatment period with 0.1% tacrolimus ointment vs. a corticosteroid ointment regimen in adults with moderate to severe AD. METHODS: Treatment was applied twice daily for a maximum of 6 months. Patients in the tacrolimus treatment group (n = 487) applied 0.1% tacrolimus ointment to all affected areas over the whole body. The patients treated with the corticosteroid regimen (n = 485) applied 0.1% hydrocortisone butyrate ointment to affected areas on the trunk and extremities and 1% hydrocortisone acetate ointment to affected areas on the face and neck. The study primary endpoint was the response rate, i.e. the proportion of patients with at least 60% improvement in the modified Eczema Area and Severity Index (mEASI) between baseline and month 3. RESULTS: By month 3, more patients in the 0.1% tacrolimus group responded to treatment (72.6% vs. 52.3% in the corticosteroid group, P < 0.001). The patients treated with 0.1% tacrolimus also showed greater improvement in mEASI, EASI, affected body surface area and physician and patient assessments of global response. Patients applying 0.1% tacrolimus ointment experienced more skin burning (52.4% vs. 13.8% in the corticosteroid group; P < 0.001). In most patients, skin burning was mild to moderate in severity and decreased rapidly after the first week of treatment. There was no increase in the incidence of infections or malignancies over time in either treatment group. CONCLUSIONS: Long-term treatment with 0.1% tacrolimus ointment is significantly more efficacious than a corticosteroid ointment regimen in adults with moderate to severe AD.

Adult↗

Scarring skin lesions of discoid lupus erythematosus are characterized by high numbers of skin-homing cytotoxic lymphocytes associated with strong expression of the type I interferon-induced protein MxA.

BACKGROUND: Infiltrating T lymphocytes are considered to play a major pathological role in skin lesions of cutaneous lupus erythematosus (CLE), a cutaneous autoimmune disease of unknown aetiology. Earlier histological studies revealed that the inflammatory infiltrate in CLE skin lesions is predominantly composed of T lymphocytes, with a slight predominance of CD4+ over CD8+ T cells, but failed to explain the development of scarring skin lesions, characteristic for chronic discoid lupus erythematosus (CDLE). Because recent investigations have highlighted the relevance of cytotoxic lymphocytes in autoimmune tissue destruction, we hypothesized that the scarring CDLE lesions might be caused by cytotoxic T lymphocytes. OBJECTIVES: To analyse skin biopsies of 15 patients with CLE [10 female, five male; localized CDLE (lCDLE), n = 5; disseminated CDLE (dCDLE), n = 5, subacute CLE (SCLE), n = 5] and five control biopsies taken from healthy controls and to characterize the inflammatory infiltrate. Methods We used immunohistochemistry, including staining for the cytotoxic molecule granzyme B, the skin-homing molecule cutaneous lymphocyte antigen (CLA) and the protein MxA, which is specifically induced by type I interferons (IFNs). RESULTS: We found a strong coexpression of granzyme B and CLA on lesional lymphocytes of patients with scarring lCDLE and dCDLE, which was significantly enhanced when compared with nonscarring SCLE and healthy controls. The increased expression of granzyme B was closely associated with the lesional expression of the type I IFN-induced protein MxA. CONCLUSIONS: Our results provide evidence that type I IFNs and potentially autoreactive cytotoxic lymphocytes targeting adnexal structures are highly associated with scarring lupus erythematosus lesions and might be responsible for their scarring character.

Biopsy↗

The mode of topical immunomodulators in the immunological network of atopic dermatitis.

For a long time, therapeutic strategies of atopic dermatitis (AD) have been dominated by the application of local or systemic steroids or other immunosuppressive agents, which have been limited by their potential for unwanted local or systemic side effects. Recently, the use of a new generation of topical nonsteroidal, immunomodulatory drugs has revolutionized the therapeutic options of this often recalcitrant allergic-inflammatory skin disease. Research work has focused on the identification of the exact mode of action and the immune specificities of the so-called 'topical immunomodulators' (TIMs) such as tacrolimus and pimecrolimus in AD. In addition to the previous findings about the mode of action of TIMs on T cells, other target cells of TIMs such as keratinocytes, mast cells, eosinophils and dendritic cells have been identified recently as potential therapeutic targets. In this overview, we provide a research update about the anti-inflammatory and anti-allergic properties of TIMs on effector cells of AD that may be involved in the complex pathophysiology of AD.

Acute Disease↗

Absence of CD26 expression on skin-homing CLA+ CD4+ T lymphocytes in peripheral blood is a highly sensitive marker for early diagnosis and therapeutic monitoring of patients with Sézary syndrome.

Patients with Sézary syndrome (SS) show clonal expansion in the peripheral blood of skin-homing CD4+ T-helper cells expressing cutaneous lymphocyte antigen (CLA). However, an increase of CLA+ CD4+ T cells can also be observed in various inflammatory dermatoses. To facilitate early diagnosis and therapeutic monitoring of SS using flow cytometry, we evaluated the expression of CD7 and CD26 on the CLA+ CD4+ lymphocyte subset. Peripheral lymphocytes from 7 patients with SS, 16 patients with mycosis fungoides (MF) and 11 healthy controls were analysed by flow cytometry for the expression of CD4, CD7, CD26, CLA and CCR4. In addition, a longitudinal study was performed over 16 months in two patients with SS. Absence of CD7 and CD26 on CLA+ CD4+ T cells was highly specific for SS. Importantly, the absence of CD26 on CLA+ CD4+ T cells was very sensitive for SS, at 100% in our patient cohort. The number of CD26- CLA+ CD4+ T cells closely correlated with therapeutic interventions in the longitudinal analysis of two patients over more than 1 year. We conclude that the absence of CD26 expression on skin-homing CLA+ CD4+ T-helper cells is a very sensitive and highly specific parameter for early diagnosis and therapeutic monitoring of patients with SS.

Antigens, CD7↗

In search for predictive factors for atopy in human cord blood.

Since early prevention is regarded as an important corner stone in the management of atopic diseases, the identification of reliable markers detecting individuals at risk are of major interest. Therefore, many efforts have been made to unravel reliable predictors for atopy which might identify children at risk and allow the initiation of preventive strategies at an early stage. In the past, much scientific energy has been forced in particular on the development of as noninvasive methods as possible to reach this goal. It is obvious that the identification of markers for atopy at the earliest time of life - namely immediately after birth - represents one of the most attractive attempts. In consequence various studies have been initiated to address this issue investigating markers for atopy in cord blood. Most of them have been geared to our current knowledge about cellular and soluble factors which are dysregulated in adolescent atopic individuals. Although the findings of these studies will improve our knowledge about the initial evolution of atopy, several parameters evaluated did not show any association or have led to almost conflicting results. In order to provide an up-date about the current developments in this field, recent research findings on predictive factors for atopy in cord blood are summarized in the following synopsis.

Antigen-Presenting Cells↗