灭活卡介苗经皮接种治疗婴幼儿哮喘对IgE ECP IFN-γ IL-4水平的影响

目的　为进一步探讨灭活卡介苗治疗婴幼儿哮喘的免疫学作用机制 ,应用灭活卡介苗经皮接种 ,观察患儿机体IgE、嗜酸性细胞阳离子蛋白 (ECP)、IFN γ、IL 4的水平变化及改变程度。方法　将哮喘患儿随机分为常规治疗组 (常规组 )与灭活卡介苗治疗组 (卡介苗组 ) ,进行 6个月的治疗后 ,观察患儿在治疗前后的IgE ,ECP ,IL 4 ,IFN γ的变化 ,另设 2 0例正常儿童作为对照组。结果　①治疗前卡介苗组和常规组IgE ,ECP与IL 4均高于对照组 ,IFN γ低于对照组 ,差异有显著性 (P <0 .0 5 ) ;卡介苗组与常规组比较差异无显著性 (P >0 .0 5 ) ;②卡介苗组治疗后ECP与IL 4低于治疗前 ,IFN γ较治疗前有升高 ,其差异均有显著性 (P <0 .0 5 ) ,IL 4和IFN γ呈明显负相关 ,且IFN γ与IL 4的变化各自均有明显的线性关系。IgE在治疗前后无显著性差异 (P >0 .0 5 )。常规组治疗前后IgE ,ECP与IL 4水平差异无显著性 ,但IFN γ水平治疗后增加 ,差异有显著性 (P <0 .0 1)。结论　灭活卡介苗治疗能刺激婴幼儿哮喘患儿IFN γ生成增多 ,下调IL 4水平 ,可能与干预治疗能诱导TH1细胞的优势分化 ,调节TH1 TH2平衡有关 ;同时 ,能降低ECP水平 ,减轻气道慢性炎症反应 ;但短期内对IgE水平未发现有显著影响。     

Macrophage migration inhibitory factor (MIF) in bronchial asthma

BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine favouring the secretion of TNFalpha and IL-8 and counteracts anti-inflammatory effects of corticosteroids. Airways inflammation is a central feature of bronchial asthma and is characterized by the accumulation of eosinophils. OBJECTIVE: The aim of this study was to investigate whether MIF is related to asthma symptoms and eosinophil accumulation in the airways. METHODS: Serum MIF levels were measured by an enzyme-linked immunosorbent assay in 44 healthy subjects and 44 asthmatics. Levels of MIF in induced sputum were measured in 10 healthy subjects and 15 asthmatics. Levels of eosinophil cationic protein (ECP) in induced sputum were measured by a radioimmunosorbent assay. Fluorescence double immunostaining was conducted to examine cellular source and localization of MIF. RESULTS: Serum MIF levels were significantly increased in asthmatic patients compared with age and sex-matched control subjects. Symptomatic patients had a higher MIF level than asymptomatic patients. Induced sputum obtained from asthmatics contained higher levels of MIF than those from control subjects. MIF levels in induced sputum were correlated with ECP levels in induced sputum. MIF was colocalized with eosinophil peroxidase staining in the cytoplasm of sputum cells. CONCLUSION: Increased MIF levels are associated with asthma symptoms and one of the cellular sources of MIF in the airways are eosinophils.     

Changes in serum ECP levels after storage at room temperature

Wantke F, Demmer CM, Götz M, Jarisch R. Changes in serum ECP levels after storage at room temperature.     

Local IgE and inflammation in chronic rhinosinusitis of asthmatics and non-asthmatics

The aim of the study was to show the difference in the pattern of inflammation, and Th1/Th2 polarization between asthmatic and non-asthmatic patients with CRS, specifically eosinophil activation, local IgE levels in the sinus fluid and tissue, and the severity of inflammation were measured. The maxillary sinus lavages, mucosal biopsies and bacteriological swabs were taken in 17 asthmatic and 36 non-asthmatic adult patients with CRS. The concentrations of IgE, eosinophil cationic protein (ECP), myeloperoxidase (MPO), and tryptase were analyzed and IgE+ cells, eosinophils, lymphocytes and plasma cells were counted. The granulocyte activation markers and IgE in sinus lavages, and the inflammatory and IgE+ cells counts were significantly higher in the asthmatics with the greatest difference in ECP and IgE concentrations. The tryptase concentrations did not differ, but only in the asthmatics they correlated significantly with the IgE concentrations and IgE+ cells count. Asthmatic patients present a distinct subgroup among the patients with chronic rhinosinusitis (CRS). The levels of the cellular markers and IgE in the sinus fluid differ from those of non-asthmatic patients with CRS. The activation of granulocytes (especially eosinophils), local IgE concentrations and the inflammatory cells infiltration are significantly higher in the asthmatics.     

Eosinophil phenotypes in bullous pemphigoid.

Eosinophil phenotypes were investigated in peripheral blood and skin lesions from eight patients with bullous pemphigoid (BP). By Nycodenz density gradients fractionation, blood eosinophils were divided into two phenotypes; normodense (greater than 1.080 g/ml) and hypodense (less than or equal to 1.080 g/ml). Increased numbers of hypodense eosinophils were observed in the blood from all patients with BP. Immunocytochemical observations, using an EG2 monoclonal antibody to react with the secretion form of eosinophil cationic protein (ECP), revealed that EG2 was expressed in 86 +/- 3% of hypodense phenotypes and 3 +/- 2% of normodense phenotypes. Ultrastructurally, hypodense eosinophils were characterized by numerous spheroidal granules, each with a lytic crystalloid core. These indicate that the hypodense phenotype represents a cell in an activated state. Only eosinophils with immunocytochemical and morphological characteristics similar to hypodense phenotypes infiltrated around the basement membrane zone in involved skin of BP. Furthermore, direct adherence of eosinophils associated with degranulation into basal keratinocytes was seen at the sites of blistering lesions. Bullous fluids contained higher concentrations of ECP than sera as determined by a radioimmunosorbent assay; thus hypodense (activated) eosinophils may directly damage the basal keratinocytes by releasing their granule proteins, subsequently leading to dermo-epidermal separation.     

Comparison of allergen-induced changes in bronchial hyperresponsiveness and airway inflammation between mildly allergic asthma patients and allergic rhinitis patients

Bronchial eosinophilic inflammation and bronchial hyperresponsiveness (BHR) are the main features of allergic asthma (AA), but they have also been demonstrated in allergic rhinitis (AR), suggesting a continuity between both diseases. In spite of not fully reproducing natural allergenic exposure, the allergen bronchial provocation test (A-BPT) has provided important knowledge of the pathophysiology of AA. Our aim was to verify the existence of a behavior of AA and AR airways different from the allergen bronchial challenge-induced airway eosinophilic inflammation and BHR changes. We studied a group of 31 mild and short-evolution AA and 15 AR patients, sensitized to Dermatophagoides pteronyssinus. The A-BPT was performed with a partially biologically standardized D. pteronyssinus extract, and known quantities of Der p 1 were inhaled. Peripheral blood (eosinophils and ECP) and induced sputum (percentage cell counts, ECP, albumin, tryptase, and interleukin [IL]-5) were analyzed, before and 24 h after A-BPT. Methacholine BHR, assessed before and 32 h after the A-BPT, was defined by M-PD20 values and, when possible, by maximal response plateau (MRP). The A-BPT was well tolerated by all the patients. AA presented a lower Der p 1 PD20 and a higher occurrence of late-phase responses (LPR). M-PD20 values decreased in AA, but not in AR, patients. MRP values increased in both groups. Eosinophils numbers and ECP levels increased in blood and sputum from both AA and AR, but only the absolute increment of sputum ECP levels was higher in AA than AR patients (P = 0.025). The A-BPT induced no change in sputum albumin, tryptase, or IL-5 values. We conclude as follows: 1) In spite of presenting a lower degree of bronchial sensitivity to allergen, AR patients responded to allergen inhalation with an eosinophilic inflammation enhancement very similar to that observed among AA. 2) MRP levels increased in both AA and AR patients after allergen challenge; however, M-PD20 values significantly changed only in the AA group, suggesting that the components of the airway response to methacholine were controlled by different mechanisms. 3) It is possible that the differences between AR and AA lie only in the quantitative bronchial response to allergen inhalation.     

The effect of eosinophils on collagen gel contraction and implications for tissue remodelling

Asthma is characterized by an eosinophilic inflammation and a subepithelial fibrosis in the airways. Eosinophils contain several cytotoxic substances, such as eosinophil cationic protein (ECP), which can promote inflammation and cause tissue damage. This has generated the hypothesis that eosinophils may drive remodelling of extracellular matrix (ECM). To investigate the role of eosinophils we used an in vitro model for remodelling, the three-dimensional collagen gel contraction assay. Two sources of eosinophils were used in this study, isolated human peripheral eosinophils (purity > 95%) and stimulated [interleukin (IL)-5, IL-3 and granulocyte macrophage-colony stimulating factor (GM-CSF)] HL-60 clone 15 cells. Human eosinophils or HL-60 cells were cast together with human lung fibroblasts (HFL1) in type I collagen gels. Both types of eosinophils augmented fibroblast-mediated collagen gel contraction in a time and concentration-dependent manner. At 48 h, the gel area in HFL1/eosinophil co-culture was 46.5% +/- 0.5 (mean +/- s.e.m.) of initial area and in HFL1 culture 52.3% +/- 0.1 (P < 0.001). Respective figures for HFL1/stimulated HL-60 co-culture and HFL1 culture only were 44.1% +/- 0.5 and 52.4% +/- 0.4 (P < 0.001). The release of ECP was increased when fibroblasts were cultured with eosinophils compared to eosinophils cultured alone. In addition, native ECP added to fibroblast gel cultures also augmented contraction. Our results suggest that eosinophils may interact with mesenchymal cells, promoting remodelling of ECM and that ECP constitutes one potential eosinophil-derived mediator driving this process. We conclude that this may be one important mechanism by which eosinophil-ECM interactions will lead to airway tissue remodelling in asthma.     

Induced sputum methodology: Validity and reproducibility of total glutathione measurement in supernatant of healthy and asthmatic individuals

Glutathione (GSH), a major antioxidant, has repeatedly been linked to the pathogenesis of pulmonary disease. The measurement of GSH in induced sputum (IS) offers a noninvasive tool for the study and monitoring of oxidative stress in airway diseases. In this study we assessed the validity and reproducibility of GSH quantification in IS from healthy subjects and individuals with mild asthma. We spectrophotometrically quantified total GSH in the IS of 31 healthy nonsmoking volunteers and 12 individuals with mild asthma. IS was processed with varying concentrations of dithiothreitol (DTT) in an effort to evaluate the effect of DTT on GSH measurements. We performed spiking experiments with defined concentrations of GSH and quantified the percentage of recovery and also analyzed the effect of induction time on GSH levels through sequential sampling of sputum portions (15, 30, and 45 minutes' induction). Finally we tested the reproducibility of GSH measurements at 2 separate time points (0 and 72 hours) and expressed it as an intraclass correlation coefficient (R(i)) with a coefficient of reliability (CR). Processing with DTT increased GSH values in IS (P <.05 for each DTT concentration > 0.001%). Recovery of GSH after spiking was complete, with a mean recovery of 102% +/- 4.8%. Increasing duration of induction led to an increase in sputum GSH (15 minutes, 10.2 +/- 2.3 micromol/L; 30 minutes, 18.4 +/- 3.5 micromol/L; 45 minutes, 26.1 +/- 4 micromol/L; P <.05 for all comparisons). Reproducibility of sputum GSH both in healthy subjects and asthmatic individuals was good (R(i) =.78, P <.001; and R(i) =.51, P =.003, respectively). With the use of standardized protocols for duration of induction and sample processing, sputum GSH measurement in healthy subjects and asthmatic individuals is valid and reproducible.