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Atopic Subjects (atopic + subject)
Selected AbstractsExhaled nitric oxide: relation to sensitization and respiratory symptomsCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2004A.-C. Olin Summary Background Conflicting data have been presented as to whether nitric oxide (NO) in exhaled air is merely reflecting atopy rather than airway inflammation. Objective To investigate the relationship between exhaled NO (eNO) and nasal NO (nNO), respiratory symptoms, and atopy, in the context of a cross-sectional study of the respiratory health of bleachery workers. Methods Two hundred and forty-six non-smoking bleachery and paper-mill workers answered a questionnaire and were examined by measurements of eNO and nNO and spirometry, outside the pollen season. Blood samples were collected and analysed for specific IgE against common aeroallergens (birch, timothy, cat and house dust mite). Atopy was defined as a positive PhadiatopÔ test. Results The atopic and the non-atopic subjects without asthma or rhinitis had similar levels of eNO. Subjects reporting asthma or rhinitis who were also sensitized to perennial allergens had higher levels of eNO, whereas those sensitized to only seasonal allergens had similar eNO levels as non-atopic subjects with asthma or rhinitis. In multiple linear regression models adjusted for nNO, eNO was associated with asthma and sensitization to perennial allergens. Conclusion The results indicate that only atopic subjects who have recently been exposed to the relevant allergen have elevated levels of eNO. Atopic subjects who are not being exposed to a relevant allergen or have never experienced symptoms of asthma or rhinitis show normal eNO. These data indicate that eNO relates to airway inflammation in atopic subjects. [source] Interleukin-16 inhibits interleukin-13 production by allergen-stimulated blood mononuclear cellsIMMUNOLOGY, Issue 1 2006Souad El Bassam Summary Expression of interleukin (IL)-16 is increased in bronchial mucosal biopsies of atopic asthmatics compared to normal controls. The functional significance of increased expression of IL-16 at sites of allergic inflammation is not yet clear. We have previously shown that IL-16 inhibits IL-5 secretion by allergen-stimulated peripheral blood mononuclear cells (PBMC). We investigated whether IL-16 inhibits the production of other T helper 2 cytokines, namely IL-13 and IL-4, by allergen-specific T cells. PBMC from ragweed-sensitive atopic subjects were stimulated with allergen extract for cytokine production in the presence or absence of rhIL-16. Production of cytokines was assessed by enzyme-linked immunosorbent assay and reverse transcription,polymerase chain reaction. To evaluate whether the modulatory effect of IL-16 on cytokine synthesis was mediated by interferon-, (IFN-,), IL-10, IL-12 or IL-18, allergen-stimulated PBMC were cultured in presence of IL-16 and neutralizing concentrations of relevant antibodies. Allergen-stimulated PBMC produced significantly elevated levels of IL-13 (90,740 pg/ml) as compared to unstimulated PBMC (0,375 pg/ml, P < 0·01). Addition of rhIL-16 resulted in down-regulation of IL-13 mRNA expression as well as significantly reduced amounts of IL-13 released by allergen-stimulated PBMC (0,457 pg/ml, P < 0·001), as observed for IL-5. No effect of IL-16 was observed on IL-4 mRNA expression. Treatment with IL-16 resulted in increased levels of IL-10 and IL-18 in allergen-stimulated cell culture. Neutralization of IFN-,, IL-12, IL-10 or IL-18 did not alter the inhibitory effects of IL-16 on IL-13 and IL-5 secretion by allergen-stimulated PBMC. IL-16 did not modify IL-13 synthesis by anti-CD3-stimulated CD4+ T cells, but it significantly reduced the production of IL-5. These data suggest that IL-16 may play an important immunoregulatory role in allergic states in response to allergen. [source] Early production of thymic stromal lymphopoietin precedes infiltration of dendritic cells expressing its receptor in allergen-induced late phase cutaneous responses in atopic subjectsALLERGY, Issue 7 2009C. J. Corrigan Background:, Thymic stromal lymphopoietin (TSLP) is an interleukin (IL)-7-like cytokine that triggers dendritic cell-mediated T helper (Th)2 inflammatory responses through a receptor consisting of a heterodimer of the IL-7 receptor alpha (IL-7R,) chain and the TSLP receptor (TSLPR), which resembles the cytokine receptor common gamma chain. Dendritic cells activated by TSLP prime development of CD4+ T cells into Th2 cells contributing to the pathogenesis of allergic inflammation. We hypothesized that allergen exposure induces expression of TSLP and results in recruitment of TSLPR bearing cells in the cutaneous allergen-induced late-phase reaction (LPR) in atopic subjects. Methods:, Skin biopsies were obtained from atopic subjects (n = 9) at various times after cutaneous allergen challenge. In situ hybridization and immunohistochemistry were used to determine TSLP mRNA expression and to measure infiltration of TSLPR+ DC in skin LPR. RT-PCR and flow cytometry were employed to analyse TSLPR expression on isolated blood DC. Results:, Allergen-induced skin TSLP expression occurred as early as 1 h after allergen challenge, whereas TSLPR+ and CD11c+ cells infiltrated relatively late (24,48 h). The majority of TSLPR+ cells were DC co-expressing blood DC antigen-1 (BDCA-1) or BDCA-2. Freshly isolated blood DC expressed both TSLPR and IL-7R, chains. Maturation and stimulation with TSLP or polyriboinosinic,polyribocytidylic acid in vitro upregulated the expression of both TSLPR and IL-7R, chains in DC but not in chemoattractant receptor-homologous molecule expressed on Th2 cells+ CD4+ T cells. Conclusion:, The data suggest that TSLP plays a role in augmenting, through DC recruitment and activation, the development of Th2-type T cells in allergic inflammation. [source] Exhaled nitric oxide and exercise-induced bronchoconstriction in young wheezy children , interactions with atopyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 7 2009L. Pekka Malmberg The association between exercise-induced bronchoconstriction (EIB) and exhaled nitric oxide (FENO) has not been investigated in young children with atopic or non-atopic wheeze, two different phenotypes of asthma in the early childhood. Steroid naïve 3- to 7-yr-old children with recent wheeze (n = 84) and age-matched control subjects without respiratory symptoms (n = 71) underwent exercise challenge test, measurement of FENO and skin prick testing (SPT). EIB was assessed by using impulse oscillometry, and FENO by standard online technique. Although FENO levels were highest in atopic patients with EIB, both atopic and non-atopic wheezy children with EIB showed higher FENO than atopic and non-atopic control subjects, respectively. In atopic wheezy children, a significant relationship between FENO and the severity of EIB was found (r = 0.44, p = 0.0004), and FENO was significantly predictive of EIB. No clear association between FENO and EIB or predictive value was found in non-atopic wheezy children. Both atopic and non-atopic young wheezy children with EIB show increased FENO levels. However, the association between the severity of EIB and FENO is present and FENO significantly predictive of EIB only in atopic subjects, suggesting different interaction between bronchial responsiveness and airway inflammation in non-atopic wheeze. [source] Highly conserved gene expression profiles in humans with allergic rhinitis altered by immunotherapyCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2005Z. Liu Summary Background Atopic diseases, resulting from hypersensitivity to a wide variety of allergens, affect 10,20% of the population. Immunotherapy is an effective treatment for atopic diseases, but its mechanisms are not fully understood. Objective We studied gene expression profiles in the peripheral blood mononuclear cells (PBMC) and examined whether the individuals with allergic rhinitis (AR) have a unique gene expression profile and how the immunotherapy affect the gene expression profiles. Methods We used cDNA microarray and ,expression analysis systemic explorer' to examine the gene expression profiles in the PBMC of atopic subjects and other groups. Results We identified a highly conserved gene expression profile in atopic subjects that permitted their accurate segregation from control or autoimmune subjects. A major feature of this profile was the under-expression of a variety of genes that encode proteins required for apoptosis and over-expression of genes that encode proteins critical for stress responses and signal transduction. We also identified 563 genes that can segregate individuals with AR based upon receipt of immunotherapy. Conclusion There is a highly conserved gene expression profile in the PBMC of individuals with AR. This profile can be used to identify individuals with AR and to evaluate responses to immunotherapy. Quantitative endpoints, such as gene expression, may assist clinicians faced with clinical decisions in the diagnosis of patients and the evaluation of response to therapy. The knowledge of the possible genetic basis for immunotherapy efficacy may also lead to novel therapeutic approaches for atopic diseases. [source] Exhaled nitric oxide: relation to sensitization and respiratory symptomsCLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2004A.-C. Olin Summary Background Conflicting data have been presented as to whether nitric oxide (NO) in exhaled air is merely reflecting atopy rather than airway inflammation. Objective To investigate the relationship between exhaled NO (eNO) and nasal NO (nNO), respiratory symptoms, and atopy, in the context of a cross-sectional study of the respiratory health of bleachery workers. Methods Two hundred and forty-six non-smoking bleachery and paper-mill workers answered a questionnaire and were examined by measurements of eNO and nNO and spirometry, outside the pollen season. Blood samples were collected and analysed for specific IgE against common aeroallergens (birch, timothy, cat and house dust mite). Atopy was defined as a positive PhadiatopÔ test. Results The atopic and the non-atopic subjects without asthma or rhinitis had similar levels of eNO. Subjects reporting asthma or rhinitis who were also sensitized to perennial allergens had higher levels of eNO, whereas those sensitized to only seasonal allergens had similar eNO levels as non-atopic subjects with asthma or rhinitis. In multiple linear regression models adjusted for nNO, eNO was associated with asthma and sensitization to perennial allergens. Conclusion The results indicate that only atopic subjects who have recently been exposed to the relevant allergen have elevated levels of eNO. Atopic subjects who are not being exposed to a relevant allergen or have never experienced symptoms of asthma or rhinitis show normal eNO. These data indicate that eNO relates to airway inflammation in atopic subjects. [source] Macrophage inflammatory protein-1, and C,C chemokine receptor-1 in allergen-induced skin late-phase reactions: relationship to macrophages, neutrophils, basophils, eosinophils and T lymphocytesCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2001S. Ying Background Macrophage inflammatory protein (MIP)-1, binds to C,C chemokine receptor (CCR)-1 with high affinity. CCR-1 is expressed on neutrophils, eosinophils, monocytes, T lymphocytes and basophils; cells characteristic of atopic allergic inflammation. In vitro, MIP-1, is chemotactic for monocytes, T cells and basophils and is also a potent histamine-releasing factor for basophils and mast cells. Although increased levels of MIP-1, were shown in atopic allergic disorders, the kinetics of expression of these CC chemokines in vivo is largely unknown. Objective To investigate the kinetics of expression of MIP-1, and receptor CCR-1 and the relationships between the expression and infiltration of inflammatory cells in allergen-induced cutaneous late-phase reactions in atopic subjects. Methods Cryostat sections, obtained from skin biopsies from 10 human atopic subjects at 6, 24, 48, 72 h and 7 days after allergen challenge, were processed for immunohistochemistry and in situ hybridization using 35S-labelled riboprobes. Results The peak expression of allergen-induced mRNA for MIP-1, and CCR-1 was 6 h. This was maintained at 24 h, and gradually returned to base line at 7 days. At 6 h, the number of cells expressing MIP-1, mRNA significantly correlated with elastase+ neutrophils and BB-1+ basophils. At 24 h, the MIP-1, mRNA+ cells significantly correlated with CD68+ macrophages. There were significant inverse correlations between the numbers of MIP-1, mRNA cells and the numbers of Tryptase+ mast cells at 6 and 24 h after allergen challenge. Conclusion Allergen-induced cutaneous late-phase reactions in humans were associated with increased expression of MIP-1, and CCR-1. This may be relevant to the infiltration of neutrophils, eosinophils, basophils and macrophages. [source] Potato lectin activates basophils and mast cells of atopic subjects by its interaction with core chitobiose of cell-bound non-specific immunoglobulin ECLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2007S. N. Pramod Summary A major factor in non-allergic food hypersensitivity could be the interaction of dietary lectins with mast cells and basophils. Because immunoglobulin E (IgE) contains 10,12% carbohydrates, lectins can activate and degranulate these cells by cross-linking the glycans of cell-bound IgE. The present objective focuses on the effect of potato lectin (Solanum tuberosum agglutinin; STA) for its ability to release histamine from basophils in vitro and mast cells in vivo from non-atopic and atopic subjects. In this study, subjects were selected randomly based on case history and skin prick test responses with food, pollen and house dust mite extracts. Skin prick test (SPT) was performed with STA at 100 µg/ml concentration. Histamine release was performed using leucocytes from non-atopic and atopic subjects and rat peritoneal exudate cells. SPT on 110 atopic subjects using STA showed 39 subjects positive (35%); however, none showed STA-specific IgE; among 20 non-atopic subjects, none were positive by SPT. Maximal histamine release was found to be 65% in atopic subjects (n = 7) compared to 28% in non-atopic subjects (n = 5); the release was inhibited specifically by oligomers of N -acetylglucosamine and correlates well with serum total IgE levels (R2 = 0·923). Binding of STA to N -linked glycoproteins (horseradish peroxidase, avidin and IgG) was positive by dot blot and binding assay. As potato lectin activates and degranulates both mast cells and basophils by interacting with the chitobiose core of IgE glycans, higher intake of potato may increase the clinical symptoms as a result of non-allergic food hypersensitivity in atopic subjects. [source] | ||||||||||||||||||||||