Proinflammatory cytokines (IL-17, IL-6, IL-18 and IL-12) and Th cytokines (IFN-gamma, IL-4, IL-10 and IL-13) in patients with allergic asthma

Allergen-reactive T helper type-2 (Th2) cells and proinflammatory cytokines have been suggested to play an important role in the induction and maintenance of the inflammatory cascade in allergic asthma. We compared the plasma concentrations of novel proinflammatory cytokines IL-17 and IL-18, other proinflammatory cytokines IL-6 and IL-12, Th2 cytokines IL-10 and IL-13, and intracellular interferon-gamma (IFN-gamma) and IL-4 in Th cells of 41 allergic asthmatics and 30 sex- and age-matched health control subjects. Plasma cytokines were measured by enzyme-linked immunosorbent assay. Intracellular cytokines were quantified by flow cytometry. Plasma IL-18, IL-12, IL-10, IL-13 concentrations were significantly higher in allergic asthmatic patients than normal control subjects (IL-18: median 228.35 versus 138.72 pg/ml, P < 0.001; IL-12: 0.00 versus 0.00 pg/ml, P = 0.001; IL-10: 2.51 versus 0.05 pg/ml, P < 0.034; IL-13: 119.38 versus 17.89 pg/ml, P < 0.001). Allergic asthmatic patients showed higher plasma IL-17 and IL-6 concentrations than normal controls (22.40 versus 11.86 pg/ml and 3.42 versus 0.61 pg/ml, respectively), although the differences were not statistically significant (P = 0.077 and 0.053, respectively). The percentage of IFN-gamma-producing Th cells was significantly higher in normal control subjects than asthmatic patients (23.46 versus 5.72%, P < 0.001) but the percentage of IL-4 producing Th cells did not differ (0.72 versus 0.79%, P > 0.05). Consequently, the Th1/Th2 cell ratio was significantly higher in normal subjects than asthmatic patients (29.6 versus 8.38%, P < 0.001). We propose that allergic asthma is characterized by an elevation of both proinflammatory and Th2 cytokines. The significantly lower ratio of Th1/Th2 cells confirms a predominance of Th2 cells response in allergic asthma.     

Increased interferon-γ- and interleukin-4-synthesizing subsets of circulating T lymphocytes in pregnant asthmatics

BACKGROUND: Pregnancy frequently interferes with the course of bronchial asthma, and asthmatic pregnant women experience less successful pregnancies. T lymphocytes synthesizing IL-4 or IFN-gamma are important in allergic mechanisms of the airways as well as in materno-fetal immunity. OBJECTIVE: We hypothesized that pregnancy (a T helper-2 polarized state) of asthmatics will enhance the number of circulating T2 lymphocytes, but decrease the subset-producing IFN-gamma (T1 lymphocytes) and thereby cause a culminating T2 dominance with possible clinical consequences. METHODS: IL-4- or IFN-gamma-producing T lymphocytes were determined by flow cytometry in healthy (n=8) and asthmatic (n=13) non-pregnant women and healthy (n=18) and asthmatic (n=48) pregnant women of similar chronological and gestational (2nd-3rd trimester) age and asthma severity (Global Initiative for Asthma II-III). RESULTS: In the blood of non-pregnant women--healthy or asthmatic--the numbers of IL-4- and IFN-gamma+ T cells were very low (<10/microL blood). In contrast, in asthmatic pregnant women, the cell counts were 182+/-27 and 39+/-6 for IFN-gamma+ and IL-4+ T cells/microL blood, respectively (both P<0.05 vs. respective control values of non-pregnant asthmatics). Within the asthmatic pregnant group, significant negative correlations were revealed between the numbers of IFN-gamma+ or IL-4+ T cells and maternal peak expiratory flow as well as birth weight of newborns (both P<0.05). CONCLUSION: These data show a previously unknown immunological interference between asthma and pregnancy. The culminating proliferation of IFN-gamma+ and IL-4+ T lymphocytes may potentially impair maternal airway symptoms as well as fetal development.     

Altered intracellular expression of the chemokines MIP-1alpha,MIP-1beta and IL-8 by peripheral blood CD4+ and CD8+ T cells in mild allergic asthma

BACKGROUND: The ability of chemokines to regulate Th1 and Th2 responses suggests a role in the pathogenesis of atopic disorders such as allergic asthma where Th2 response dominance has been observed. Although the impact of allergic asthma on local chemokine production in the lung has been the subject of investigation, little is know about the influence of disease progression on peripheral chemokine production. We now report use of whole blood culture and flow cytometry to assess the influence of mild allergic asthma on peripheral T-cell chemokine expression. METHODS: Study participants included patients with mild allergic asthma (n = 7) and nonasthmatic controls (n = 7). Following in vitro stimulation of peripheral venous blood with phorbol 12-myristate acetate (PMA) and ionomycin, flow cytometry was used to estimate the percentage of CD4+ and CD8+ T cells producing a number of chemokines, including macrophage inflammatory proteins MIP-1alpha and MIP-1beta, RANTES (regulated on activation, T-cell expressed and secreted), monocytic chemotactic protein-1 (MCP)-1, and interleukin (IL)-8, or the cytokines interferon (IFN)-gamma and IL-4. Serum levels of MIP-1alpha, MIP-1beta, RANTES, MCP-1, IL-8, IFN-gamma and IL-4 were also assessed by quantitative ELISA. RESULTS: Intracellular expression of MIP-1beta by CD4+ and CD8+ T cells from allergic asthmatics was significantly reduced in comparison to that observed for nonasthmatics (median = 2.29% (1.75-3.50) vs 4.57% (3.38-6.64), P = 0.05; 14.20% (13.18-17.88) vs 44.10% (30.38-48.70), P = 0.01). Similarly, intracellular expression of MIP-1alpha by CD8+ T cells from allergic asthmatics was also significantly lower (3.67% (1.17-5.42) vs 17.10% (4.97-20.43), P = 0.05). Conversely, IL-8 expression by both CD4+ and CD8+ T cells from allergic asthmatics demonstrated significant enhancement (9.93% (7.77-11.28) vs 4.14% (3.61-7.11), P = 0.05; 8.40% (6.97-10.04) vs 4.98% (3.37-6.08), P = 0.05). Examination of intracellular IFN-gamma and IL-4 revealed no significant difference in the expression of either cytokine by CD4+ T-cells from allergic asthmatics and nonasthmatics. In contrast, expression of IFN-gamma was significantly reduced in CD8+ T-cells from allergic asthmatics (24.60% (21.08-32.50) vs 48.40% (41.50-55.28), P = 0.01). CONCLUSIONS: The occurrence in mild allergic asthma of peripheral T-cell chemokine expression suggestive of a diminished Th1 response, coinciding with marginal change in cytokine profiles indicative of a Th2 response bias, confirms the importance of chemokine involvement in the etiology of allergic asthma. The ability to use whole blood culture to estimate chemokine expression in T cell subsets may ultimately provide a practical means to evaluate disease status and to monitor early intervention therapies which target chemokines.     

Cytokine production from sputum cells after allergenic challenge in IgE-mediated asthma

BACKGROUND: Th2 cytokine production from airway cells is thought to govern the eosinophilic airways inflammation in allergic asthma. Induced sputum has become a widely used technique to assess airways inflammation. METHODS: By applying the technique of induced sputum to collect airways cells, we have assessed the spontaneous production of a set of cytokines, including interleukin-4, 6, 10, interferon-gamma and tumour necrosis factor-alpha, 6 h after a bronchial allergenic challenge with Dermatophagoides pteronyssinus (Dpt) in 12 sensitized asthmatics and compared the results obtained after inhalation of saline as control. A group of eight healthy non-allergic subjects was enrolled to control for any non-specific effect of Dpt. Cytokines were measured by a dynamic immunoassay during a 24-h sputum cell culture. RESULTS: Allergen challenge in sensitized asthmatics caused an acute and a late bronchospasm together with a rise in sputum eosinophil counts. Afterwards allergen sputum cells from allergic asthmatics displayed a rise in their production of IL-4 (P < 0.01), IL-6 (P < 0.05) and IL-10 (P < 0.05) when compared to saline. By this time sputum generation of IL-4 in atopic asthmatics was greater than in healthy subjects (P < 0.001). Furthermore, in allergic asthmatics there was a strong correlation between the rise in interleukin-4 production from sputum cells and the rise in sputum eosinophils (r = 0.87, P < 0.001). CONCLUSIONS: Sputum cell culture is a useful model to assess cytokine production in allergic asthmatics who show a marked up-regulation of Th2 cytokines following acute allergen exposure. The rise in sputum eosinophil count following allergen challenge strongly correlates with the rise in IL-4 generation from sputum cells.     

Nasal endoscopy in asthmatic children: assessment of rhinosinusitis and adenoiditis incidence, correlations with cytology and microbiology

BACKGROUND: Upper respiratory airway diseases may induce a worsening of asthma. Sinusitis represents one of the most common chronic diseases. The association of asthma and sinusitis varies greatly in different studies, depending on diagnostic procedures. OBJECTIVE: The aims were: (i) to demonstrate that nasal endoscopy may be easily feasible in asthma at paediatric age; (ii) to evaluate the incidence of rhinosinusitis and adenoiditis in children with asthma by nasal endoscopy; (iii) to correlate inflammatory parameters such as cytology and microbiological cultures with nasal endoscopy findings. SUBJECTS AND METHODS: One hundred and forty-five asthmatic children were evaluated, 48 males and 97 females, with an average age of 7.27 years. Evaluated parameters were the incidence of rhinosinusal infections in asthmatic children, and the role of: (i) nasal endoscopy, (ii) nasal cytology, and (iii) nasal microbiology in their diagnoses. RESULTS: Nasal endoscopy was successfully performed on 128 patients. Twenty-six children had endoscopic rhinosinusitis alone, 10 had adenoiditis alone, and 35 showed endoscopic rhinosinusitis associated with adenoiditis. There were significant correlations between endoscopic rhinosinusitis and adenoiditis (P < 0.001), between clinical and endoscopic rhinosinusitis (P < 0.001), between endoscopic rhinosinusitis and adenoiditis and microbiology (P < 0.05 and P < 0.0001, respectively), and between microbiology and cytology (P < 0.05). CONCLUSION: This study shows that rhinosinusal infections are common in asthmatic children. Moreover, nasal endoscopy might represent a fruitful tool in the management of asthmatic children.     

Improvement of clinical and immunopathologic parameters in asthmatic children treated for concomitant chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis is frequently associated with asthma. A Th2 cytokine pattern has been recently reported in chronic rhinosinusitis in asthmatic children. OBJECTIVE: To evaluate the effects of treating concomitant chronic rhinosinusitis on respiratory symptoms and function and immunopathological parameters in asthmatic children. METHODS: Eighteen children with moderate asthma (age range, 5 to 12 years) poorly controlled by high doses of inhaled corticosteroids and chronic rhinosinusitis were evaluated for symptoms, spirometry, and inflammation at baseline, after treatment, and 1 month after suspension of treatment. All of the children were treated with a combination of amoxicillin and clavulanate (20 mg/kg twice daily) and fluticasone propionate aqueous nasal spray (100 microg/d) for 14 days. A short course of oral corticosteroids was also prescribed (deflazacort, 1 mg/kg daily for 2 days, 0.5 mg/kg daily for 4 days, and 0.25 mg/kg daily for 4 days). Rhinosinusal lavage for cytokine measurements and a nasal scraping for cytologic analysis were performed in all patients before and after medical treatment. RESULTS: A negative endoscopy result was demonstrated in 15 children after treatment. Symptoms and respiratory function significantly improved after treatment and 1 month later; 8 children had intermittent asthma and 10 had mild asthma. A significant reduction of inflammatory cell numbers was detected in all asthmatic children. Interleukin 4 levels significantly decreased (P < 0.001), whereas interferon-y levels increased (P < 0.001). CONCLUSION: Treatment of chronic rhinosinusitis is able to improve symptoms and respiratory function in asthmatic children, reducing inflammatory cells and reversing the cytokine pattern from a Th2 toward a Th1 profile.     

Differential mediator release from basophils of allergic and non-allergic asthmatic patients after stimulation with anti-IgE and C5a

The differentiation between allergic and non-allergic asthma is a common and important challenge for the clinician. Until now, no in vitro diagnostic characteristics have been described to distinguish between these types. To examine the diagnostic value of a basophil stimulation test, we compared anti-IgE- and C5a-induced mediator release from peripheral blood leucocytes in different types of bronchial asthma. Peripheral blood leucocytes (PBL) from 10 aspirin-sensitive asthmatics (ASA), 12 non-allergic asthmatics without aspirin intolerance (NAA), seven allergic asthmatics (AA), and nine healthy controls were prepared by dextran sedimentation. After priming with interleukin-3 (IL-3) PBL were stimulated with anti-IgE and C5a, and the release of histamine (HR) and sulfidoleukotrienes (LTR) in the supernatant was compared. Additionally, purified leucocyte fractions were studied to determine the cellular source of mediator release. Upon stimulation with anti-IgE LTR was slightly, but not significantly, lower in ASA and NAA compared to AA and controls. In contrast, C5a-triggered LTR was significantly higher in ASA (14.4 +/- 12.88 pg/105 cells) and NAA (22.9 +/- 22.61 pg/105 cells) than in AA (9.6 +/- 3.29 pg/105 cells) and controls (7.5 +/- 7.19 pg/105 cells) (P < 0.05). This difference between ASA and NAA vs. AA and controls was even more pronounced when determining the quotient C5a-/anti-IgE-induced LTR (P < 0.001). At an optimal cut-off point of 1.0, calculated by relative operating characteristics (ROC) analysis, the positive predictive value for a donor to belong to ASA or NAA was 0.94. No significant differences could be found in HR between the asthmatic patient groups and healthy controls in either condition. As cellular source of LTR and HR the basophil could be determined. Determination of anti-IgE- and C5a-induced LTR from basophils allows us to discriminate between allergic and non-allergic asthmatic patients. For diagnostic purposes the quotient C5a-/anti-IgE-induced LTR is more significant than considering a single parameter. ASA cannot be distinguished from NAA.     

小儿慢性丙型肝炎外周血T细胞亚群和TH1/TH2型细胞因子的研究

目的通过研究小儿慢性丙型肝炎外周血T细胞亚群及TH1/TH2型细胞因子的表达,进一步探讨小儿慢性丙型肝炎的免疫发病机制。方法(1)流式细胞仪(FACS)检测16例慢性丙型肝炎患儿及10例正常对照外周血T细胞亚群。(2)将慢性丙型肝炎患儿和正常对照外周血单个核细胞(PBMC)体外培养72h后,用ELISA法检测培养上清中TH1型细胞因子(IFN-γ、IL-2、IL-12和TNF-γ)和TH2型细胞因子(IL-4、IL-10)的浓度。结果(1)CD4 细胞无明显变化。CD8 细胞与正常对照比较明显升高(P<0.05)。CD3 细胞升高,CD4 /CD8 比值下降,但与正常对照比较无统计学意义(P>0.05)。(2)PBMC培养上清中IFN-γ、IL-10和TNF-α的水平明显升高(P<0.01),而没有检测到IL-2、IL-4、IL-12的基础分泌。结论慢性丙型肝炎患儿体内T淋巴细胞存在数量和功能的异常,CD8 细胞数升高,CD4 细胞功能异常,表现在以TH2型细胞因子的分泌为主。这可能与丙肝病毒(HCV)感染的慢性化有关。     

Airway neutrophil inflammation in nonasthmatic patients with food allergy

BACKGROUND: Patients with food allergy (FA) have been recently shown to develop bronchial hyperresponsiveness (BHR), despite the absence of any concomitant asthmatic manifestation. In order to explain this observation, we sought to examine the presence of a bronchial inflammation in induced sputum of nonasthmatic patients with FA. METHODS: Twelve nonasthmatic patients with FA (urticaria, digestive symptoms, anaphylaxis) were included in the study. Results were compared to these obtained from eight asthmatic patients without food allergy and eight healthy controls. Diagnosis of FA was based on double-blind placebo-controlled challenge. Sputum cells and fluid-phase eosinophil cationic protein (ECP), myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured in induced sputum. BHR was evaluated using methacholine inhalation. RESULTS: Sputum from asthmatics, in comparison with the sputum of healthy subjects and patients with FA contained a higher proportion of eosinophils and higher levels of ECP (< 0.001). In marked contrast, patients with FA exhibited an increased proportion of neutrophils and IL-8 in comparison with asthmatics and controls (P < 0.05 for neutrophils and P < 0.001 for IL-8). There was a significant correlation between sputum neutrophils and IL-8 (r = 0.68, P < 0.001). MPO levels were not different between the groups. There was a trend toward higher levels of IL-8 and ECP in food allergic patients with BHR in comparison with patients with FA without BHR. CONCLUSION: Our results demonstrate that a subclinical neutrophil airway inflammation is present in patients with food allergy free of clinical respiratory symptoms and that IL-8 may be an important mediator of this neutrophilia.     

Relationship between changes in interferon-γ production by peripheral blood T cells and changes in peak expiratory flow rate in patients with chronic stable asthma

BACKGROUND: Cytokines production by T helper lymphocytes (Th cells), which orchestrate the interplay of the different cells involved in airway inflammation of asthma, may be reflected in peripheral blood. Some studies have suggested that the Th cell cytokines by peripheral blood T cells correlate with asthma severity. OBJECTIVE: To investigate the relationship between changes in IFN-gamma production by peripheral blood T cells and changes in lung function in chronic stable asthmatics. METHODS: Sixteen patients with chronic stable moderate asthma aged 35-65 years (nine women) were recruited. Morning and evening peak expiratory flow rates (PEFR) monitoring and blood sampling for peripheral blood T cell culture, total IgE and blood eosinophils were performed at baseline and week 12. Levels of IFN-gamma, IL-4 and IL-5 in culture supernatants of peripheral blood T cell were determined by using enzyme-linked immunosorbent assay (ELISA) kits. RESULTS: Patients with increased IFN-gamma changes from baseline showed significantly increased changes in morning (P = 0.02) and evening (P < 0.05) PEFR compared with those with decreased IFN-gamma changes. The changes in IFN-gamma production and IFN-gamma: IL-4 ratio significantly correlated with the changes in morning PEFR (Rs = 0.59, P < 0.02; Rs = 0.63, P < 0.01, respectively) and tended to correlate with the changes in evening PEFR (Rs = 0.45, P = 0.08; Rs = 0.5, P = 0.05, respectively). The changes in IL-4 and IL-5 did not correlate with the changes in IgE and blood eosinophils, respectively. CONCLUSIONS: These findings suggest that IFN-gamma may be associated with the alteration of lung function in asthmatics and play a role in the pathophysiology of chronic stable asthma.     

Acid-base equilibrium in exhaled breath condensate of allergic asthmatic children

BACKGROUND: The dysregulation of airway pH control may have a role in asthma pathophysiology. The measurement of exhaled breath condensate (EBC) pH and ammonia levels may be used as a noninvasive method to study acid-base status in the airway of asthmatics. METHODS: Exhaled breath condensate from 29 allergic stable asthmatic children and 13 healthy controls was collected by cooling exhaled air during tidal breathing. Ammonia was measured by high-performance liquid chromatography with fluorescence detection. pH was measured after deaeration of EBC samples by bubbling with argon. The children also underwent FENO measurement. RESULTS: Both pH and ammonia values in EBC were significantly lower in the asthmatics than in the control group [pH: ICS-treated (median and interquartile range) 7.70 (7.62-7.74), steroid-naive 7.53 (7.41-7.68), controls 7.85 (7.80-7.90), P <0.01 and P <0.001, respectively; ammonia: ICS-treated 476.17 microM (282.50-594.80), steroid-naive 253.24 microM (173.43-416.08), controls 788.30 microM (587.29-1310.39), P < 0.05 and P <0.001, respectively]. Both pH and ammonia values were higher in ICS-treated than in steroid-naive asthmatic children. There was a significant correlation between EBC pH and ammonia concentrations. CONCLUSIONS: These data show that EBC pH values of stable asthmatic children are lower compared with those of healthy controls and positively correlated with ammonia concentrations, supporting the hypothesis that airway acidification may have a role in the pathobiology of allergic asthma.     

Increased T helper 1 cytokine responses by circulating T cells are present in women with recurrent pregnancy losses and in infertile women with multiple implantation failures after IVF

BACKGROUND: We aimed to study T-helper 1 (Th1) and Th2 intracellular cytokine expression in peripheral blood lymphocytes of women with recurrent spontaneous abortions (RSA) or infertility with multiple implantation failures after IVF cycles. METHODS: Twenty-six women with three or more RSA and 23 with two or more IVF failures (14 with no history of spontaneous abortion (SAB) and nine with more than one SAB) comprised the two study groups. Twenty-one non-pregnant healthy multiparous women served as controls. Proportions (%) of lymphocytes containing IFN-gamma, TNF-alpha, IL-4 and IL-10 and the Th1/Th2 ratios of IFN-gamma/IL-4, IFN-gamma/IL-10, TNF-alpha/IL-4 and TNF-alpha/IL-10 in CD3+, CD3+/CD8- (T helper) and CD3+/CD8+ (T suppressor) cells were measured by 4-colour flow cytometry. RESULTS: RSA women demonstrated significantly higher Th1/Th2 ratios of IFN-gamma/IL-4 (P < 0.01), TNF-alpha/IL-4 and TNF-alpha/IL-10 (P < 0.05 each) in CD3+/CD8- T helper cells than those of controls. The proportion of TNF-alpha producing CD3+/CD8- cells (P < 0.05), and the Th1/Th2 ratios of TNF-alpha/IL-4 (P < 0.05) and TNF-alpha/IL-10 (P < 0.005) in CD3+/CD8- cells were significantly higher in women with multiple IVF failures without SAB as compared with those of controls. CONCLUSIONS: The prevalence of dominant Th1 immune responses in peripheral blood lymphocytes may reflect the systemic contribution of Th1 cytokines to RSA or multiple implantation failures in IVF cycles.     

Allergen-induced bronchial inflammation in house dust mite-allergic patients with or without asthma

BACKGROUND: It is presently unknown which factors determine the occurrence and persistence of asthma in house dust mite-allergic individuals. The level of allergen-specific IgE antibodies does not seem to be decisive for asthmatic symptoms. Moreover, levels of exposure to mite allergens do not seem to differ significantly between asthmatic and non-asthmatics individuals. AIM: It was hypothesized that the presence or absence of asthmatic symptoms in house dust mite-allergic patients is associated with quantitative or qualitative differences in the cellular bronchial inflammatory response during the late phase of the allergic reaction. This hypothesis was tested in the bronchial allergen challenge model. MATERIAL AND METHODS: Whole lung challenges with house dust mite extract were performed in 52 house dust mite-allergic subjects, of whom 26 had asthma and 26 had perennial rhinitis without asthmatic symptoms. Primary outcomes were parameters for bronchial inflammation in serial samples of induced sputum (cell differentials, eosinophil cationic protein (ECP), interleukin-8 (IL-8), myeloperoxydase (MPO)). In addition, lung function, non-specific bronchial hyper-responsiveness and serial blood samples (eosinophils and IL-5) were analysed. RESULTS: At baseline sputum eosinophils and ECP were similar in both groups but neutrophils and IL-8 were higher in asthmatics. The early bronchoconstriction after allergen challenge was similar in asthma and non-asthmatic rhinitis (median decrease in FEV1: asthma -31.7% vs. non-asthmatics -29.1%, P > 0.1). The late phase bronchoconstriction was significantly greater in asthma (median decrease in FEV1: asthma -27.6% vs. non-asthmatics -18.9%, P = 0.02). Induction of bronchial hyper-responsiveness was similar in both groups. Bronchial allergen challenge elicited significant increases in sputum eosinophils and ECP, which were indistinguishable for both groups (P > 0.1 and P = 0.07, respectively). In contrast, higher numbers of neutrophils persisted in asthma 24h after challenge and were accompanied by significant increases in IL-8 and MPO, which were absent in non-asthmatics (difference between groups P = 0.007 and P = 0.05, respectively). CONCLUSION: Allergen challenge inducedvery similar increases in eosinophils and ECP in induced sputum in allergic asthmatics and in allergic non-asthmatic patients. The difference in bronchial inflammation between asthma and non-asthmatic rhinitis appeared to be more closely related to indices for neutrophilic inflammation.     

Atopic dermatitis in young children is associated with impaired interleukin-10 and interferon-γ responses to allergens, vaccines and colonizing skin and gut bacteria

BACKGROUND: A significant proportion of children with food allergy and more severe forms of atopic dermatis (AD) go on to develop persistent forms of allergic disease such asthma. Defining immune dysregulation in these children will be of great value in understanding disease pathogenesis. OBJECTIVE: In this study we characterized the immune responses of young infants (6-18 months of age) with moderate-to-severe AD (a modified SCORAD>or=25) and compared these (n=53) with responses of non-allergic children with no history of dermatitis or sensitization of the same age (n=20). METHODS: Mononuclear cell cytokine responses to allergens (egg ovalbumin (OVA), beta-lactoglobulin (BLG), house dust mite (HDM)), vaccines (tetanus toxoid (TT), diphtheria toxoid (DT)), intestinal flora (heat-killed Lactobacillus species (HKLB)), heat-killed Staphylococcus aureus (HKSA), S. aureus enterotoxin B (SEB) and mitogen (phytohaemaglutinin (PHA)) were compared in children with AD with unaffected children. RESULTS: Children with AD had significantly lower spontaneous (unstimulated) production of regulatory cytokine IL-10 (P<0.001), as well as IFN-gamma (P<0.001) and TNF-alpha (P<0.001) compared with the unaffected children. After allowing for differences in baseline levels IL-10 responses to virtually all stimuli (food allergens (P=0.003), vaccines P=0.01, intestinal flora (heat-killed Lactobacillus species (HKLB), P=0.005) and skin flora (heat-killed Staphylococcus aureus (HKSA), P=0.003)) were also significantly attenuated in children with AD. The only exception was HDM, to which responses were stronger in children with AD [P=0.05]. Although there were no significant correlations between HDM IgE and HDM cytokine responses at this age, T-helper type 2 (Th2) IL-5 (P=0.014) and IL-13 (P=0.004) responses to HDM were significantly more frequent in the children with AD. However, while children with AD showed significantly attenuated Th1 IFN-gamma responses to food allergens (OVA, P=0.007 and BLG, P<0.001) and vaccines (DT, P=0.008 and TT, P<0.001), these children showed no difference in Th1 IFN-gamma responses to HDM or microbial agents (HKSA and HKLB). CONCLUSION: A increase in propensity for Th2 responses to aeroallergens in children with AD is associated with early impaired production of IL-10 regulatory cytokine to a broad range of environmental stimuli including foods, intestinal flora, S. aureus, and vaccines.     

Reduced IL-12 level correlates with decreased IFN-gamma secreting T cells but not natural killer cell activity in asthmatic children.

BACKGROUND: Accessory cells such as macrophages and natural killer cells, and their cytokines such as IL-10, IL-12, and IFN-gamma have been suggested to play a critical role in the development of T helper cells. OBJECTIVE: Both natural killer cells and peripheral blood mononuclear cells were isolated and stimulated for their ability in producing cytokines. In addition, the percentage of IFN-gamma-secreting cells was analyzed with the method of intracellular staining. RESULTS: The data suggested (1) no significant difference between asthmatic children and normal controls in number, cytotoxicity, and IFN-gamma production of purified NK cells; (2) decreased secretion of IL-12 by stimulated peripheral blood mononuclear cells in asthmatic children compared with normals (P < .05); (3) decreased production of IFN-gamma by PBMC from asthmatic children compared with normals (P < .05); and (4) intracellular expressed IFN-gamma level was lower in CD4+ T cells of asthmatic children (P < .05). CONCLUSION: The results suggested that IL-12 produced predominantly by macrophages and associated decreased IFN-gamma-secreting CD4+ T cells play a critical role in the pathogenesis of asthma.     

Patterns of food allergen-specific cytokine production by T lymphocytes of children with multiple allergies

BACKGROUND: The contribution of different T cell subsets to the overall measured cytokine response to food allergens is largely unexplored. METHOD: The patterns of cytokine production of peripheral blood-derived T cells after allergen stimulation were studied in 22 children with multiple food allergies and in 20 non-allergic children as controls, using flow cytometry. RESULTS: Proportions of T cells of food-sensitized children spontaneously secreting IFN-gamma and IL-10 (without antigen stimulation) were lower than non-atopic children and adult controls (P相似文献   

High serum levels of tumour necrosis factor‐α and interleukin‐8 in severe asthma: markers of systemic inflammation?

BACKGROUND: Severe asthma is characterized by elevated levels of pro-inflammatory cytokines and neutrophilic inflammation in the airways. Blood cytokines, markers of 'systemic' inflammation, may be a feature of amplified inflammation in severe asthma. OBJECTIVE: To detect differences in IL-8, TNF-alpha, IL-16 and IL-13 levels in the serum(s) of stable severe and mild-moderate asthmatics related to blood leucocytes proportion, airway calibre and exhaled nitric oxide (NO) levels. METHODS: We assessed cytokine serum levels by ELISA and blood leucocyte counts by an alkaline peroxidase method in 20 healthy controls, 22 mild-moderate [forced expiratory volume in 1 s (FEV1)(%pred): 89+/-3] and 14 severe asthmatics [FEV1(%pred): 49+/-2]. RESULTS: IL-8 and TNF-alpha levels were higher in severe asthmatics than in mild-moderate asthmatics or in controls (P<0.05). No differences in IL-16 and IL-13 levels were detected. Severe asthmatics showed higher circulating neutrophil and eosinophil number than controls (P<0.05). In severe asthmatics, exhaled NO levels were superior than in controls (P<0.05), but inferior than in mild-moderate asthmatics (P<0.05). We found positive correlation between TNF-alpha levels and exhaled NO (r=0.67; P=0.01) or circulating neutrophil counts (r=0.57; P=0.03) in severe asthmatics. CONCLUSION: sTNF-alpha and sIL-8 are markers of 'systemic' inflammation in severe asthmatics, in conjunction with augmented circulating neutrophils, suggesting the involvement of neutrophil-derived cytokine pattern in severe asthma.     

T cell and eosinophil activation in mild and moderate atopic and nonatopic children's asthma in remission

BACKGROUND: Inflammation in the pathogenesis of asthma is associated with products of activated T cells and eosinophils. The aim of this study was to determine whether ongoing inflammation persists in children with different phenotypes of asthma despite the disease in remission. METHODS: Serum samples were collected from 68 children with atopic or nonatopic asthma in remission and from 15 healthy children. Soluble interleukin-2 receptor (sIL-2R), IL-2 and IL-4 were examined by using an enzyme-linked immunosorbent assay. Total and specific immunoglobulin E, and eosinophil cationic protein (ECP) were analysed by fluoroimmunoassay (Pharmacia CAP System). RESULTS: In patients with moderate persistent atopic asthma, sIL-2R was increased significantly when compared with mild persistent atopic asthma (P < 0.05). No changes of sIL-2R were seen in nonatopic asthmatics compared with atopics and controls. The level of IL-2 was elevated in moderate persistent atopic and nonatopic asthmatic children compared with controls (P < 0.05 and P < 0.05 respectively) and compared with mild persistent atopic asthmatics and mild persistent nonatopic asthmatics (P < 0.05 in both cases). The levels of IL-4 in most patients and controls remained below the sensitivity of the assay. Eosinophil cationic protein levels in moderate persistent atopic and nonatopic asthmatics were significantly higher than in mild persistent asthma severity cases (P < 0.001 and P < 0.01 respectively) and in healthy children (P < 0.01 in both cases). CONCLUSION: Changes in the concentration of sIL-2R, IL-2 and ECP reflect increased T cell and eosinophil activity in relation to the level of severity of asthma in atopic and nonatopic children, thereby proving the presence of persistent inflammation despite the absence of disease symptoms.     

Oral provocation tests with aspirin and food additives in asthmatic patients

Aspirin and food additives are known to induce bronchoconstriction, angioedema or urticaria in susceptible patients. To evaluate the incidence of hypersensitivity to aspirin and food additives, 36 subjects with bronchial asthma, 33 of whom were non-allergic asthmatics and 3 were allergic asthmatics who had a history of aspirin sensitivity, were challenged orally with six compounds: acetylsalicylic acid (ASA), sodium bisulfite, tartrazine, sodium benzoate, 4-hydroxy benzoic acid, and monosodium L-glutamate. Significant bronchoconstrictions were found in 15 (41.7%) of the 36 subjects tested. Eight of the 15 subjects showed positive asthmatic responses to the aspirin, two showed asthmatic responses to the food additives, and five responded to both aspirin and the food additives. It is suggested that ASA and food additives could be causes of clinically significant bronchoconstriction in moderately severe non-allergic asthmatic patients.