气道嗜酸性粒细胞增高与COPD加重

有证据表明部分COPD加重期气道嗜酸性粒细胞增高,其原因可能与病毒感染有关;了解COPD加重期气道嗜酸性粒细胞增高的发病机制,认识伴有嗜酸性粒细胞增高的气道炎症对临床治疗中是否选择糖皮质激素有一定价值,本文就这方面进展作一综述.     

全身短期应用糖皮质激素治疗加重期慢性阻塞性肺疾病气道炎性细胞因子的产生

探讨对全身短期应用糖皮质激素对慢性阻塞性肺疾病(COPD)患者加重期气道炎症和肺功能的影响。对59例COPD加重期患者给予地塞米松5mg静脉滴注5d,10d内减量至停用。治疗前后分别进行肺功能检查测定FEV1.0及FEV1.0占预计值百分数(FEV1.0pre),并收集诱导痰液分析炎性细胞变化。按照痰液嗜酸粒细胞占白细胞百分数升高与否分为嗜酸粒细胞增高组20名(A组)和非嗜酸粒细胞增高组39名(B组)。健康对照组13名为C组。检测治疗前后上清液白介素8(IL-8)、肿瘤坏死因子α(TNF-α)、嗜酸粒细胞阳离子蛋白(ECP)、内皮素1(ET-1)的变化。与B组比较,A组治疗后Eos/Leu百分率下降(P<0.05),其他细胞比例无变化。B组治疗后炎性细胞占白细胞比例无变化。治疗后两组患者IL-8、TNF-α均明显下降(P<0.05),A组TNF-α下降明显(P<0.05)。治疗后A组ECP及ET-1显著降低,而B组变化不明显。全身短期应用糖皮质激素可改善加重期COPD患者的肺功能及气道炎症,在诱导痰液嗜酸粒细胞升高者效果更明显,与激素抑制嗜酸粒细胞气道炎症有关。中和实验,中和效价分别为10-1.8/10μl、10-1.6/10μl。由此表明,该抗独特型抗体疫苗具有良好的免疫原性。     

支气管哮喘患者血清骨桥蛋白和嗜酸细胞趋化因子表达及临床意义

支气管哮喘是慢性气道炎症性疾病,嗜酸性粒细胞在气道炎症反应中起重要作用[1]。现认为细胞因子网络失衡是发病的基础,而Th2细胞因子、嗜酸细胞趋化因子(eotaxin)共同诱导的嗜酸性粒细胞募     

豚鼠哮喘模型气道中炎症细胞浸润与c—jun表达的关系

观察豚鼠哮喘模型致敏原激发后４，１２，２４ｈ气道中炎症细胞的浸润及炎症细胞内ｃ－ｊｕｎ表达情况。结果表明，激发后４ｈ气道壁有轻度炎症细胞浸润，至１２和２４ｈ气道炎症细胞浸润加重，粘膜上皮及粘膜下层有大量中性粒细胞和嗜酸性粒细胞，气道结构破坏；各时点炎症细胞内均有ｃ－ｊｕｎ的表达，与对照组比较差异显著     

IL-13在哮喘中的作用

支气管哮喘是以Th2型细胞因子增高和气道高反应性为特征的变态反应性疾病。白细胞介素 13(IL 13)是近年来新克隆的Th2型细胞因子 ,它通过诱导B细胞增殖和分化 ,促进IgE合成 ,活化嗜酸性粒细胞 ,延长嗜酸性粒细胞的存活 ,诱导气道高反应性等机制 ,在哮喘的发生中起重要的作用。     

070 IL-13在哮喘中的作用

支气管哮喘是以Th2型细胞因子增高和气道高反应性为特征的变态反应性疾病.白细胞介素-13(IL-13)是近年来新克隆的Th2型细胞因子,它通过诱导B细胞增殖和分化,促进IgE合成,活化嗜酸性粒细胞,延长嗜酸性粒细胞的存活,诱导气道高反应性等机制,在哮喘的发生中起重要的作用.     

嗜酸性粒细胞计数与冠心病危险因素相关分析

目的 探讨白细胞中的嗜酸粒细胞计数与冠心病影响因素的相关性.方法 收集128例非急性冠状动脉造影患者一般资料,进行血细胞参数、生化指标等检测.冠状动脉造影确定冠状动脉病变部位及损伤程度.根据嗜酸性粒细胞计数分组,进行趋势分析,判断冠心病患者危险因素与嗜酸性粒细胞计数相关性.结果 患者按嗜酸性粒细胞计数分三组(＜0.1×109/L;0.1～0.2×109/L;＞0.2×109/L).嗜酸性粒细胞增高与男性性别、经皮冠状动脉介入治疗或冠脉再造术呈正相关.嗜酸性粒细胞增高与血小板计数、血红蛋白、白细胞计数、血肌酐、甘油三酯、糖化血红蛋白等冠心病危险因素呈正相关(P＜0.01),与高密度脂蛋白呈负相关(P＜0.01).趋势分析显示,多支血管病变、左主干病变、冠脉内血栓、慢性阻塞、支架内再狭窄等参数在不同嗜酸性粒细胞分组中的差异有统计学意义(P＜0.05).结论 嗜酸性粒细胞增高与冠心病患者的危险因素有一定关联.     

IL—13在哮喘中的作用

支气管哮喘是以Th2型细胞因子增高和气道高反应性为特征的变态反应性疾病。白细胞介素-13(IL-13)是近年来新克隆的Th2型细胞因子，它通过诱导B细胞增殖和分化，促进IgE合成，活化嗜酸性粒细胞，延长嗜酸性粒细胞的存活，诱导气道高反应性等机制，在哮喘的发生中起重要的作用。     

原癌基因表达与哮喘气道炎症

目的:观察原癌基因表达与气道炎症细胞浸润的关系。方法:卵蛋白致敏豚鼠,复制哮喘模型。Dot-blot\,Northern-blot分子杂交及免疫组织化学技术观察哮喘发作前、后豚鼠气道上皮及肺组织中c-fos\,c-myc\,c-jun和c-sis的表达及其与炎症细胞浸润的关系。结果:正常豚鼠气道及肺组织中c-fos\,c-mycmRNA无或很少表达,极少炎症细胞浸润。哮喘发作后,豚鼠气道上皮及肺组织c-fos\,c-mycmRNA表达明显增加。免疫组织化学研究显示Fos、Myc、Jun及Sis在正常豚鼠气道及肺组织低水平表达,哮喘发作后即刻,4种原癌基因表达产物明显增加,气道内有少量淋巴细胞、嗜酸性粒细胞及中性粒细胞浸润;12-24h,上述细胞浸润加重,粘膜下层及粘膜上皮内以中性粒细胞和嗜酸性粒细胞浸润为主。结论:原癌基因表达与气道炎症在哮喘发病中有密切关系。     

嗜酸性粒细胞募集在支气管哮喘发病中的作用

支气管哮喘是一种气道慢性炎症性疾病,伴有嗜酸性粒细胞增多、杯状细胞肥大、黏液分泌增多、可逆性的气道阻塞及对吸入变应原和非特异性刺激的高反应性等特点,其中嗜酸性粒细胞募集和随后的激活在支气管哮喘发病中起着十分重要的作用。本文就嗜酸性粒细胞募集在支气管哮喘发病机制中的研究进展作一综述,为支气管哮喘的治疗提供一线新的曙光。     

Overlap Between Asthma and COPD: Where the Two Diseases Converge

Asthma and chronic obstructive pulmonary disease (COPD) are traditionally recognized as distinct diseases, with some clearly separate characteristic. Asthma originates in childhood, is associated with allergies and eosinophils, and is best treated by targeting inflammation, whereas COPD occurs in adults who smoke, involves neutrophils, and is best treated with bronchodilators and the removal of risk factors. However, the distinction between the two is not always clear. Patients with severe asthma may present with fixed airway obstruction, and patients with COPD may have hyperresponsiveness and eosinophilia. Recognizing and understanding these overlapping features may offer new insight into the mechanisms and treatment of chronic airway inflammatory diseases.     

Inhibition of human interleukin-13-induced respiratory and oesophageal inflammation by anti-human-interleukin-13 antibody (CAT-354)

BACKGROUND: Allergic asthma is a complex disorder characterized by local and systemic T helper type 2 -cell responses such as the production of IL-13, a cytokine associated with the induction of airway hyper-responsiveness (AHR), chronic pulmonary eosinophilia, airway mucus overproduction and eosinophilic oesophagitis. OBJECTIVE: Our study aimed to address the therapeutic potential of a human anti-human IL-13 IgG4 monoclonal antibody (CAT-354) in a murine model of respiratory and oesophageal inflammation induced by intratracheal human IL-13. METHODS: BALB/c mice were treated on days 1 and 3 with CAT-354 (intraperitoneal injection), and human IL-13 was injected intratracheally on days 2 and 4. AHR to methacholine, airway eosinophilia in bronchoalveolar lavage fluid, histologic analysis of goblet cell metaplasia and oesophageal eosinophilia were evaluated. RESULTS: Human IL-13 induced airway eosinophilia and goblet cell metaplasia in mice in a dose-dependent manner. Moreover, intratracheal dosing with 25 microg of human IL-13 was sufficient to induce AHR, goblet cell metaplasia and oesophageal eosinophilia. Pretreatment with CAT-354 significantly reduced AHR, airway eosinophilia and oesophageal eosinophilia. CONCLUSION: These results demonstrate that anti-human IL-13 (CAT-354) is a potential therapeutic treatment for allergic airway and oesophageal diseases.     

Role of interleukin-12 and stat-4 in the regulation of airway inflammation and hyperreactivity in respiratory syncytial virus infection

Respiratory syncytial virus (RSV) is a respiratory pathogen that can cause significant morbidity in infants and young children. Interestingly, the majority of children who acquire a RSV infection do not exhibit severe symptoms. Development of a Th1 response has been associated with resolution of symptoms in viral infections and may explain mild RSV illness. The current study investigated the cytokine response observed in mild disease in C57BL/6 mice that had low airway resistance and mucus production with little pulmonary inflammation. RSV infection in these mice was accompanied by a fourfold increase in interleukin-12(IL-12). Treatment of RSV-infected mice with anti-IL-12 resulted in an increase in airway hyperreactivity, mucus production, and airway inflammation (eosinophilia). Since IL-12 activation is dependent on Stat-4-mediated intracellular signal transduction, similar experiments were performed in Stat-4 deficient mice and demonstrated similar results to those obtained from anti-IL-12 treated mice. Again, there was an increase in airway hyperreactivity and mucus production, and goblet cell hypertrophy. These studies support the importance of IL-12 in the immune response to RSV infection resulting in resolution of disease and protection from inappropriate inflammatory responses.     

IL-6 induced by double-stranded RNA augments allergic inflammation via suppression of Foxp3+ T-cell/IL-10 axis

Activation of innate immunity against viruses in the respiratory tracts affects the development of asthma. Most respiratory viruses generate double-stranded (ds)RNA during their replication. We recently showed that a low-dose administration of polyinosinic polycytidylic acid (poly IC), a mimetic of viral dsRNA, during allergen sensitization augments airway eosinophilia and hyperresponsiveness in mice via enhanced production of IL-13 from T cells. However, a phenotype of asthma under severer load of dsRNA remains unknown. d-galactosamine (d-GalN) is known as a strong sensitizer of poly IC. Mice were treated with poly IC plus d-GalN during allergen sensitization. A sublethal dose of poly IC/d-GalN augmented airway eosinophilia and CD4(+) T-cell accumulation in the lungs but not airway hyperresponsiveness. The augmented inflammation was associated with decreased IL-10 in the bronchoalveolar lavage fluid and decreased Foxp3(+) regulatory T cells in the lungs. Serum IL-6 was prominently higher in the mice treated with poly IC/d-GalN than in that with poly IC alone or d-GalN alone. Poly IC/d-GalN did not affect IL-17-producing T cells in the lungs. Poly IC/d-GalN failed to augment airway eosinophilia after anti-IL-10 receptor monoclonal antibody treatment during allergen challenge. Finally, anti-IL-6 receptor monoclonal antibody treatment before poly IC/d-GalN completely prevented the decrease of IL-10 and Foxp3(+) regulatory T cells and the augmentation of airway inflammation. These results indicate that enhanced production of IL-6 by poly IC/d-GalN induces the augmentation of allergic inflammation via suppression of Foxp3(+) regulatory T-cell/IL-10 axis. IL-6 may be a target for preventing asthma augmentation related to severe virus infection.     

Cigarette smoke synergistically enhances respiratory mucin induction by proinflammatory stimuli

Pathogenic factors associated with chronic obstructive pulmonary disease (COPD), such as cigarette smoke, proinflammatory cytokines, and bacterial infections, can individually induce respiratory mucins in vitro and in vivo. Since co-presence of these factors is common in lungs of patients with COPD, we hypothesized that cigarette smoke can amplify mucin induction by bacterial exoproducts and proinflammatory cytokines, resulting in mucin hyperproduction. We demonstrated that cigarette smoke extract (CSE) synergistically increased gene expression and protein production of MUC5AC mucin induced by LPS or TNF-alpha in human airway epithelial NCI-H292 cells. CSE also enhanced expression and production of MUC5AC mucin induced by epidermal growth factor receptor (EGFR) ligands TGF-alpha and amphiregulin, as well as LPS- and TNF-alpha- induced expression and/or release of TGF-alpha and amphiregulin. Furthermore, (4-[(3-bromophenyl)amino]-6,7-diaminoquinazoline), a potent inhibitor of EGFR, blocked synergistic induction of MUC5AC mucin. H(2)O(2) mimicked the synergistic effects of CSE, while antioxidant N-acetyl-L-cysteine prevented synergistic induction of MUC5AC mucin by CSE. In a rat model of LPS-induced airway inflammation, concurrent cigarette smoke inhalation enhanced mucin content of the bronchoalveolar lavage fluid, muc5AC gene expression, and mucous cell metaplasia in the airways. These results suggest that cigarette smoke has the potential to synergistically amplify induction of respiratory mucins by proinflammatory stimuli relevant to COPD pathogenesis and contribute to mucin hyperproduction observed in patients with COPD.     

Role of viral infections in asthma and chronic obstructive pulmonary disease

Substantial evidence implicates common respiratory viral infections in the pathogenesis of asthma and chronic obstructive pulmonary disease (COPD). Children who experience recurrent virally induced wheezing episodes during infancy are at greater risk for developing asthma. In addition, respiratory viral infections are a major trigger for acute exacerbations of both asthma and COPD. Despite the importance of viral infections in asthma and COPD, the mechanisms by which viruses predispose to, or cause exacerbations of, these diseases remain poorly understood. It is clear that viral infections lead to enhanced airway inflammation and can cause airways hyperresponsiveness. The epithelial cell is the principal site of viral infection in the airways and plays a central role in viral modulation of airway inflammation via release of a variety of cytokines, chemokines, and growth factors. The mechanisms by which viral infections modulate epithelial function, therefore, is a topic of intense investigation. The epithelium also contributes to the host innate defense response to viral infection by releasing products that are antiviral and/or can lead to increased recruitment of dendritic cells and lymphocytes. Some evidence supports a role for the epithelial cell in specific immunity, although the response of more conventional cells of the immune system to viral infections is likely the dominant factor in this regard. Although current therapies may help combat virally induced disease exacerbations, they are less than ideal. A better understanding of the mechanisms underlying viral modulation of these diseases, therefore, may lead to new therapeutic approaches.     

Role of respiratory viral infections in the development of atopic conditions

PURPOSE OF REVIEW: Respiratory viral infections are implicated in both protection from, and inception of, allergic airway disease. Severe lower respiratory tract viral infections are associated with recurrent wheeze, asthma and atopy. It is unclear if this association is causal and the underlying mechanisms governing this are unknown. Whilst respiratory viral infections are the major precipitants of acute exacerbations of wheezing illness, early life infections are also clearly associated with protection from allergic diseases. This article aims to review the current understanding of the complex relationship between lower respiratory tract viral infections and their impact upon development of atopy in the airway. RECENT FINDINGS: Clinical studies and animal models have further demonstrated that lower respiratory tract viral infections are strongly associated with development of recurrent wheeze and asthma with human rhinoviruses being shown to be the most prevalent cause of lower respiratory tract viral infections in infants, along with associated asthma development. A case-control study provided evidence of a contributory role for respiratory viral infections within this association, whilst recent experimental studies provide a possible mechanistic insight. SUMMARY: Progress into understanding the relationship between respiratory viral infections and allergic airway disease is essential for development of treatments aimed at treating common risk factors mediating association but not cause. Recent findings may have begun to identify key pathways open to therapeutic intervention.     

Rhinovirus infections: induction and modulation of airways inflammation in asthma

There is renewed interest in the role of respiratory virus infections in the pathogenesis of asthma and in the development of exacerbations in pre-existing disease. This is due to the availability of new molecular and experimental tools. Circumstantial evidence points towards a potentially causative role as well as to possibly protective effects of certain respiratory viruses in the cause of allergic asthma during early childhood. In addition, it now has become clear that exacerbations of asthma, in children as well as adults, are mostly associated with respiratory virus infections, with a predominant role of the common cold virus: rhinovirus. Careful human in vitro and in vivo experiments have shown that rhinovirus can potentially stimulate bronchial epithelial cells to produce pro-inflammatory chemokines and cytokines, may activate cholinergic- or noncholinergic nerves, increase epithelial-derived nitric oxide synthesis, upregulate local ICAM-1 expression, and can lead to nonspecific T-cell responses and/or virus-specific T-cell proliferation. Experimental rhinovirus infections in patients with asthma demonstrate features of exacerbation, such as lower airway symptoms, variable airways obstruction, and bronchial hyperresponsiveness, the latter being associated with eosinophil counts and eosinophilic cationic protein levels in induced sputum. This suggests that multiple cellular pathways can be involved in rhinovirus-induced asthma exacerbations. It is still unknown whether these mechanisms are a distinguishing characteristic of asthma. Because of the limited effects of inhaled steroids during asthma exacerbations, new therapeutic interventions need to be developed based on the increasing pathophysiological knowledge about the role of viruses in asthma.     

Disseminated Trichosporon asahii infection presenting as eosinophilia in an immunocompetent patient: A case report

Trichosporon are naturally found in external environments and are a part of the normal flora of the human skin, respiratory tract, and gastrointestinal tract. Disseminated Trichosporon infection occurs sporadically in patients with immunodeficiency, and is mainly manifested as blood, urine, catheter, and thorax/peritoneum infections, rarely as lymphatic, liver and spleen infections. Elevated blood eosinophil granulocyte from Trichosporon infection have rarely been reported. Here, we report a rare Case of eosinophilia associated with lymphatic and liver and spleen infections due to Trichosporon asahii in an immunocompetent patient. No reports of eosinophilia from Trichosporon infections other than lung, to our knowledge, have been published.     

γδT cells suppress inflammation and disease during rhinovirus-induced asthma exacerbations

Most asthma exacerbations are triggered by virus infections, the majority being caused by human rhinoviruses (RV). In mouse models, γδT cells have been previously demonstrated to influence allergen-driven airways hyper-reactivity (AHR) and can have antiviral activity, implicating them as prime candidates in the pathogenesis of asthma exacerbations. To explore this, we have used human and mouse models of experimental RV-induced asthma exacerbations to examine γδT-cell responses and determine their role in the immune response and associated airways disease. In humans, airway γδT-cell numbers were increased in asthmatic vs. healthy control subjects during experimental infection. Airway and blood γδT-cell numbers were associated with increased airways obstruction and AHR. Airway γδT-cell number was also positively correlated with bronchoalveolar lavage (BAL) virus load and BAL eosinophils and lymphocytes during RV infection. Consistent with our observations of RV-induced asthma exacerbations in humans, infection of mice with allergic airways inflammation increased lung γδT-cell number and activation. Inhibiting γδT-cell responses using anti-γδTCR (anti-γδT-cell receptor) antibody treatment in the mouse asthma exacerbation model increased AHR and airway T helper type 2 cell recruitment and eosinophilia, providing evidence that γδT cells are negative regulators of airways inflammation and disease in RV-induced asthma exacerbations.