Sy, Hing Yee. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves lxxiv-xciv). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese; appendixes I-III in Chinese.

A resposta proliferativa das células mononucleares do sangue periférico dos adultos com dermatite atópica mostrou-se diminuída após estímulos com mitógenos (enterotoxinas estafilocócicas A e B, "pokeweed" e fitohemaglutinina) e antígenos (toxóide tetânico e Candida albicans). A correlação positiva dos níveis séricos de interleucina-18, IgE e escore de gravidade da doença sugerem que esta citocina seria um marcador de atividade da dermatite atópica do adulto / A reduced proliferative response of peripheral blood mononuclear cells in adults with atopic dermatitis was detected when stimuli with mitogens (staphylococcal enterotoxins A and B, phytohemaglutinin, pokeweed), and with antigens (tetanus toxoid and Candida albicans) were performed. A positive correlation of interleukin-18, IgE levels and severity scores of the disease suggest that this cytokine could be a marker of disease activity in adult atopic dermatitis

A resposta proliferativa das células mononucleares do sangue periférico dos adultos com dermatite atópica mostrou-se diminuída após estímulos com mitógenos (enterotoxinas estafilocócicas A e B, "pokeweed" e fitohemaglutinina) e antígenos (toxóide tetânico e Candida albicans). A correlação positiva dos níveis séricos de interleucina-18, IgE e escore de gravidade da doença sugerem que esta citocina seria um marcador de atividade da dermatite atópica do adulto / A reduced proliferative response of peripheral blood mononuclear cells in adults with atopic dermatitis was detected when stimuli with mitogens (staphylococcal enterotoxins A and B, phytohemaglutinin, pokeweed), and with antigens (tetanus toxoid and Candida albicans) were performed. A positive correlation of interleukin-18, IgE levels and severity scores of the disease suggest that this cytokine could be a marker of disease activity in adult atopic dermatitis

A dermatite de contato alérgica (DCA) ao íon níquel (Ni2+) é uma dermatose inflamatória frequente nos países industrializados. Envolve a ativação de células T específicas ao Ni2+, seguida da proliferação e indução de um perfil misto de citocinas, tanto pró-inflamatórias quanto reguladoras, sugerindo que vários subtipos de células T (helper - Th e citotóxica - Tc) estão envolvidos na resposta imune. Este estudo teve como objetivo a análise das citocinas TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 e IL-23 pela técnica de imuno-histoquímica, para tentar identificar a prevalência de um ou mais subtipos de células T (Th/Tc), nos eczemas crônico e agudo de pacientes com DCA ao Ni2+. Avaliamos 20 pacientes (17 mulheres e 3 homens, com idade mediana de 46 anos) apresentando eczema crônico, pelo contato cotidiano do paciente com o Ni2+. Foram coletadas duas biópsias de pele em cada um dos 20 pacientes, a primeira no local do eczema crônico ao Ni2+, antes da aplicação do teste de contato (TC); e a segunda no local do eczema agudo, provocado pelo TC com o sulfato de níquel, 48 horas após sua fixação, nas leituras positivo forte (++) ou positivo muito forte (+++). Foram 160 amostras de eczema agudo e 160 de eczema crônico, perfazendo um total de 320 amostras. Apenas três amostras foram excluídas devido a algum tipo de falha técnica, como, por exemplo, o descolamento dos cortes de pele da lâmina. Para a análise dos dados utilizou-se o software estatístico STATA versão 13. As amostras coradas revelaram resultados positivos para as oito citocinas estudadas, e estas apresentaram valores heterogêneos. Esta heterogeneidade foi medida pelo coeficiente de variação, indicando a variabilidade do conjunto dos dados obtidos. O TNF-alfa, IFN-y, IL-4, IL-13 e IL-17 tiveram prevalência maior no eczema crônico do que no eczema agudo, a IL-2 e IL-23 apresentaram maior prevalência no eczema agudo, em comparação com o eczema crônico e a IL-10 apresentou prevalência similar tanto no eczema agudo quanto no crônico, porém, estas prevalências foram muito baixas, em ambos os eczemas. O TNF-alfa foi a citocina que mais prevaleceu no eczema crônico e a IL-2 foi a mais prevalente no eczema agudo. Porém, estas prevalências foram estatisticamente significantes apenas para a IL-4 e IL-13. Verificamos, nos eczemas crônico e agudo, a presença de um perfil misto de citocinas dos subtipos de células T (Th/Tc), sugerindo que as respostas imunes são expressas ao mesmo tempo. Entretanto, são necessários mais estudos para uma compreensão mais ampla sobre o perfil das citocinas na DCA ao Ni2+, o que poderia levar a novas abordagens terapêuticas / Allergic contact dermatitis (ACD) to nickel (Ni+2) is a inflammatory dermatosis, common in industrialized countries. It involves the activation of nickel-specific T cells, followed by the proliferation and induction of a mixed profile of both proinflammatory and regulatory cytokines, suggesting that several T cell subtypes (helper - Th and cytotoxic - Tc) are involved in the immune response. This study aimed to analyze the cytokines TNF-alfa, INF-y, IL-2, IL-4, IL-10, IL-13, IL-17 and IL-23 using the immunohistochemistry technique in order to try to identify the prevalence of one or more T cell subtypes (Th/Tc) in the chronic and acute eczema of patients with ACD to Ni+2. We evaluated 20 patients (17 women and 3 men, median age of 46 years) with chronic eczema, by the patient\'s daily contact with Ni+2. Two skin biopsies were collected in each of the 20 patients, the first at the site of the chronic eczema to Ni+2, prior to the application of the contact test (CT); and the second at the site of acute eczema caused by CT with nickel sulphate, 48 hours after its fixation in the strong positive (++) or very strong positive (+++) readings. There were 160 samples of acute eczema and 160 of chronic eczema, a total of 320 samples. Only three samples were excluded due to some kind of technical failure, such as detachment of the skin cuts from the microscope slide. Statistical software STATA version 13 was used to analyze the data. The stained samples showed positive results for the eight cytokines studied, and these presented heterogeneous values. This heterogeneity was measured by the coefficient of variation, indicating the variability of the data set obtained. TNF-alfa, IFN-y, IL-4, IL-13 and IL-17 had a higher prevalence in chronic eczema than in acute eczema, IL-2 and IL-23 were more prevalent in acute eczema compared to chronic eczema and IL-10 presented similar prevalence in both acute and chronic eczema, however, a very low prevalence in both eczema. TNF-alfa was the most prevalent cytokine in chronic eczema and IL-2 was the most prevalent in acute eczema. However, these prevalences were statistically significant only for IL-4 and IL-13. In chronic and acute eczema, we observed the presence of a mixed cytokine profile of the T cell subtypes (Th/Tc), suggesting that immune responses are expressed at the same time. However, further studies are needed for a broader understanding of the cytokine profile in ACD to Ni+2, which could lead to new therapeutic approaches

INTRODUÇÃO: A dermatite atópica (DA) é uma doença cutânea inflamatória, acompanhada por prurido intenso e xerose cutânea. A etiopatogenia da DA é multifatorial, envolvendo fatores genéticos, ambientais e imunológicos, dentre outros. OBJETIVOS: Avaliar a influência das enterotoxinas A e B do Staphylococcus aureus (SEA e SEB) na resposta mediada por células Th17 e Th22 nos indivíduos adultos com DA. MÉTODOS: Foram selecionados 38 pacientes adultos com DA e um grupo controle com 40 indivíduos adultos, pareados por idade e gênero Os métodos utilizados foram: 1) ELISA: dosagem dos níveis séricos de IL-6, IL-17, IL-22 e IL-12p40/IL-23 e em sobrenadantes de culturas de células mononucleares do sangue periférico (PBMC) estimuladas com SEA e SEB; 2) Imuno-histoquímica: análise da expressão de IL-17 em fragmentos de pele; 3) Citometria de fluxo: a) análise das citocinas circulantes em amostras de soro: IL-2, IL-4, IL-5, IL-6, IL-10, TNF, IL-17A e IFN-y b)avaliação das células T CD4+ mono e polifuncionais secretoras de IL-17, IL-22, TNF, IFN-y, MIP-1beta, e expressão do marcador de ativação celular CD38; c) células Th22 e Tc22 estimuladas com SEA e SEB. RESULTADOS: 1) Através do ELISA, a secreção de IL-22 sérica e em PBMC induzidas por SEA e SEB foi significativamente mais elevada, quando comparada ao grupo controle; 2) houve aumento na expressão de IL-17 em amostras de pele de doentes de DA através da imuno-histoquímica; 3) Através da citometria de fluxo, foram detectados: a) níveis séricos de IL-2, 5, 6, 10, 17A e IFN-y elevados no grupo com DA em relação aos controles; houve diferença significativa nos níveis circulantes de IL-17A nos pacientes com DA moderada e grave; b) na avaliação monofuncional das células T CD4+ sob estímulo de SEA/SEB, houve redução da expressão das citocinas IFN-y, IL-17A, IL-22 ou TNF na DA, quando comparadas ao grupo controle; na análise polifuncional das células T CD4+/CD8+, ocorreu redução da resposta na DA em relação aos controles; nos pacientes atópicos encontramos aumento da resposta em situação basal na dependência de CD38, e redução na resposta frente a SEA/SEB na ausência de CD38; c) encontramos resposta reduzida das células Th22, e elevada de células Tc22 frente aos estímulos SEA e SEB, nos pacientes com DA. CONCLUSÕES: O estudo corrobora o papel patogênico das enterotoxinas estafilocócicas na DA. A ativação crônica com superantígenos estafilocócicos pode contribuir com a alta frequência de células T CD4+ CD38+ polifuncionais, e com a resposta polifuncional anérgica, mediadas por células T CD38- / BACKGROUND: Atopic dermatitis (AD) is an inflammatory skin disease with intense itching and xerosis. AD pathogenesis is multifactorial, involving genetic, environmental, and immunological factors, among others. OBJECTIVES: To evaluate the influence of enterotoxins A and B from Staphylococcus aureus (SEA and SEB) in Th17 and Th22 cell response in adults with AD. METHODS: We evaluated 38 adult patients with AD, and a control group of 40 adults, age and gender matched. Assays: 1) ELISA: evaluation of IL-6, IL-17, IL-12p40/IL-23 and IL-22 serum levels and in supernatants of mononuclear cell cultures from peripheral blood (PBMC), stimulated with SEA/SEB; 2) Immunohistochemistry: analysis of IL-17 expression in skin specimens; 3) Flow cytometry: a) analysis of circulating cytokines in serum samples: IL-2, IL-4, IL-5, IL-6, IL-10, TNF, IL-17A and IFN-y b) evaluation of mono and polyfunctional TCD4+ cells that secrete IL-17, IL-22, TNF, IFN-y, MIP-1beta, and expression of the activation marker CD38; c) analysis of Tc22 and Th22 cells stimulated with SEA and SEB. RESULTS: 1) Secretion of IL-22 in the serum and from supernatants of cell cultures from PBMC, stimulated with SEA and SEB were higher in AD patients, when compared to the control group by ELISA; 2) there was an increase of IL-17 expression in skin samples by immunohistochemistry; 3) Flow cytometry showed: a) elevated serum levels of IL-2, 5, 6, 10, 17A and IFN-y in AD, when compared to controls; there was a significant difference in circulating levels of IL-17A in patients with moderate and severe disease; b) monofunctional evaluation of T CD4+ cells under SEA/SEB stimuli showed reduced expression of IFN-y, IL-17A, IL-22 or TNF cytokines in AD, compared to controls; the same was observed for polyfunctional CD4+/CD8+ T cells analysis, exhibiting a diminished response in AD. In atopic patients under basal conditions, there was an augmented CD38- dependent response and reduced pattern to SEA/SEB in the absence of CD38; c) finally, we observed a reduced response of Th22 cells and enhanced Tc22 cells under SEA/SEB stimuli in patients with AD. CONCLUSIONS: This study corroborates the pathogenic role of staphylococcal enterotoxins in AD. Chronic activation with staphylococcal superantigens may contribute to the high frequency of polyfunctional CD4 +CD38+ T cells and with the anergic polyfunctional response mediated by T CD38- T cells

No description available.

Background: Pimecrolimus cream 1% is a non-steroid, selective inflammatory cytokine inhibitor indicated for atopic dermatitis (AD). Objective: To compare the safety and efficacy of pimecrolimus cream 1%-based treatment versus conventional therapy in adults with moderate AD. Methods: Patients were randomized to receive pimecrolimus cream 1% (n = 62) or vehicle (n = 68) at the first signs/symptoms of AD, for 24 weeks as required. A moderately potent topical corticosteroid (prednicarbate 0.25% cream) was allowed in both groups to treat flares. Results: Corticosteroids were required on fewer days in the pimecrolimus group, compared with the vehicle group (9.7 vs. 37.8%, p < 0.001). Furthermore, 59.7% of pimecrolimus-treated patients experienced no flares during the study period, compared with 22.1% of vehicle-treated patients (p < 0.001). Pimecrolimus cream 1% was well tolerated throughout the study. Conclusion: For adults with moderate AD, pimecrolimus cream 1% is well tolerated, reduces the incidence of flares, reduces/eliminates corticosteroid use, improves long-term disease control and enhances the patients’ quality of life. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Allergic manifestations are increasingly common in infants and children. Accumulating evidence suggests that the ‘epidemic’ increase of childhood allergy may be associated with environmental factors such as stress. Although the impact of stress on the manifestation and exacerbation of allergy has been demonstrated, the underlying mechanisms of stress-induced exacerbation are still obscure. A growing number of studies have suggested an altered hypothalamus-pituitary-adrenal (HPA) axis function to stress in allergic children. It is speculated that a dysfunctional HPA axis in response to stress may facilitate and/or consolidate immunological aberrations and thus, may increase the risk for allergic sensitization and exacerbation especially under stressful conditions. In the present review the potential impact of a hyporesponsive as well as a hyperresponsive HPA axis on the onset and chronification of childhood allergy is summarized. Moreover, potential factors that may contribute to the development of an aberrant HPA axis responsiveness in allergy are discussed. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.

Bovine Dermatitis digitalis (DD) ist eine weltweit verbreitete Infektionskrankheit bei Rindern, die primär die plantare Haut über dem Kronenrand nahe des Zwischenzehenspalts der Hinterklauen betrifft. Schmerzhafte ulzero-proliferative Läsionen mit akuten und chronischen Erscheinungsformen führen zu Verhaltensänderungen und Lahmheit der Tiere. DD hat damit einen erheblichen Einfluss auf deren Wohl und ihre Leistungen. Zahlreiche Untersuchungen zur Ätiologie der Krankheit ergaben, dass es sich um das Zusammenspiel verschiedener Ursachen handelt. Einer synergistischen multifaktoriellen Infektion mit starker Beteiligung von Bakterien der Gattung Treponema kommt dabei besondere Bedeutung zu. Aspekte wie Tierhaltung, Hygienestandards und genetische Prädispositionen wurden ebenfalls intensiv untersucht. Nichtsdestotrotz bleiben Infektionsherde, Transmissionsrouten und Pathomechanismen weitgehend unklar. Zum besseren Verständnis der Ereignisse, die zu DD-Läsionen führen, sollte im Zuge dieser Arbeit ein organotypisches Zellkulturmodell der bovinen Haut erstellt werden, welches in späteren Versuchen mit dem Krankheitserreger zum Einsatz kommen soll. Verlässliche und reproduzierbare Techniken zur Isolation und Kultur von bovinen primären Keratinozyten und Fibroblasten wurden etabliert; geeignete Zellkulturmedien für die Langzeitkultivierung und –aufbewahrung der Hautzellen wurden identifiziert. Zur Erstellung des Hautmodells wurden zwei verschiedene Ansätze miteinander verglichen. Der zweite Ansatz, bei dem Keratinozyten direkt auf ein dermales Äquivalent, d.h. ein Pad aus bovinem Kollagen I mit eingesäten post-mitotischen Fibroblasten, gesät wurden, brachte ein vielversprechendes Hautmodell hervor. Die inkorporierten post-mitotischen Fibroblasten wiesen eine charakteristische Zellmorphologie mit intakten Nuklei auf. Die terminale Differenzierung der Keratinozyten auf dem dermalen Äquivalent wurde mittels Immunfluoreszenzfärbungen mit Antikörpern gegen die Markerproteine Keratin 14 und Desmoglein 1 gezeigt. Die Ergebnisse erster Experimente mit Treponema spp. verdeutlichen, dass das Hautäquivalent ein geeignetes Modell zur Untersuchung der Pathogenese der DD darstellt. / Bovine digital dermatitis (DD) is a worldwide occurring, infectious disease in cattle primarily affecting the plantar skin above the coronary band near the interdigital cleft on hind feet. Painful ulceroproliferative lesions with acute and chronic appearances lead to behavioral changes and lameness. Hence, DD has a major impact on animal welfare and performance. Substantial efforts in investigating the etiology of the disease revealed a synergistic origin with evidence for a multibacterial infection and the strong involvement of bacteria from the genus Treponema. As the interaction between host, pathogen and environment is not negligible, surrounding circumstances such as housing, general hygiene and genetic predispositions have been investigated intensively. Nevertheless, infection reservoirs, transmission routes and pathomechanisms remain widely unclear. To better understand the cellular and molecular events during Treponema-infection of bovine skin, it was the specific aim of this study to establish an organotypic in vitro skin model, which could be challenged with the causative agent of the disease. A technique to reliably and reproducibly isolate primary keratinocytes and fibroblasts from the site of infection was established. Appropriate cell culture media for the long-term cultivation and storage of bovine skin cells were identified. Two different methods to develop the skin model were compared. The second strategy in which keratinocytes were directly seeded on top of a dermal equivalent, i.e. a bovine collagen type I pad with embedded post-mitotic fibroblasts, gave rise to a promising organotypic skin equivalent. The incorporated post-mitotic fibroblasts showed a characteristic cell morphology with intact nuclei. The terminal differentiation of the keratinocytes on top of the dermal equivalent was shown with anti-K14 and anti-Dsg1 immunofluorescence stainings. The results of initial Treponema-experiments proved that the skin equivalent is a suitable model to investigate the underlying mechanisms during Treponema-infection of bovine skin and hence, the pathogenesis of DD.