Interleukin-10-Secreting regulatory T cells in allergy and asthma

Allergic diseases, including asthma, are chronic inflammatory disorders originating from an aberrant immune response to innocuous antigens in our environment (allergens). In susceptible individuals, sensitization to allergen leads to the induction of allergen-specific Thelper type 2 (Th2) responses and immunoglobulin E (IgE) production. Subsequent challenge with allergen results in IgE-mediated mast cell activation and the recruitment and activation of effector cells, leading to clinical symptoms of disease. In this review, we discuss evidence that the anti-inflammatory cytokine interleukin-10 (IL-10) offers therapeutic promise for the control of asthma and allergy. We highlight the potential role of IL-10 secretion by a specialized T-cell subset, T regulatory cells, to prevent allergic inflammation in healthy individuals and to provide long-term relief from disease symptoms in allergic patients.     

Immunological Changes After Hyposensitization in House-Dust-Sensitive Asthmatic Children: A Review

Patients with allergic diseases are characterized by the presence of elevated total serum IgE and specific IgE antibodies against a variety of environmental allergens. To explore the causes for augmented IgE antibody production and the working mechanisms of hyposensitization (HS), a series of studies has been conducted on house-dust-sensitive, newly diagnosed, and hyposensitized asthmatic children and normals.

The specific IgE and IgG antibodies were measured by radioallergosorbent test; the lymphoproliferative capability was measured by ³H-thymidine incorporation; the allergen-specific suppressor activity was determined by the extent of house-dust-activated, interleukin-2 (IL-2)-expanded lymphocytes to suppress the allergen-induced proliferation of autologous mononuclear cells (MNC); and IL-2 was produced by stimulating MNC with allergen or phytohemagglutinin (PHA) and quantitated by its capability to support the proliferation of mouse IL-2-dependent cytotoxic T-cell line.

The results showed: 1) HS was effective in 90% of patients in terms of decreased attacks and medication taken; 2) the patients were defective in suppressor T-cell function for IgE production; 3) HS was able to restore the regulatory T-cell function and increase the production of IgG-blocking antibody; and 4) IL-2 production may be used as an indicator for initiation and discontinuation of HS.

Therefore, hyposensitization is an effective and specific treatment for allergic bronchial asthma and can partially correct an immunoregulatory aberration in atopic individuals.     

Beneficial effects of Galectin-9 on allergen-specific sublingual immunotherapy in a Dermatophagoides farinae-induced mouse model of chronic asthma

Background

Allergen-specific sublingual immunotherapy is a potential disease-modifying treatment for allergic asthma. Galectin-9 (Gal-9), a β-galactoside-binding protein with various biologic effects, acts as an immunomodulator in excessive immunologic reactions by expanding regulatory T cells (Treg) and enhancing transforming growth factor (TGF)-β signaling. We investigated the efficacy of sublingually administered Gal-9 as an adjuvant to a specific allergen in a Dermatophagoides farinae (Df)-induced mouse model of chronic asthma.

A protective role for the fifth complement component (c5) in allergic airway disease

RATIONALE: Reports from our laboratory, as well as those from others, have documented the importance of complement activation, the C3a anaphylatoxin, and its receptor, C3aR, in promoting Th2 effector functions in a mouse model of bronchopulmonary allergy. Although deficiency in the fifth complement component (C5) has been linked to enhanced airway hyperresponsiveness in mice, the contribution of C5 to other major biological hallmarks of asthma has not been evaluated. OBJECTIVE: Accordingly, congenic C5-sufficient and C5-deficient mice were subjected to a mouse model of bronchopulmonary allergy to assess the impact of C5 on pulmonary inflammation and Th2 effector functions in experimental asthma. METHODS AND MAIN RESULTS: In contrast to observations reported for C3- and C3aR-deficient animals, C5-deficient mice exhibited significantly increased airway hyperresponsiveness relative to wild-type congenic control mice after antigen challenge. Moreover, challenged C5-deficient mice had a 3.4-fold and 2.7-fold increase in the levels of airway eosinophils and lung interleukin (IL)-4-producing cells, respectively, compared with challenged wild-type mice. Consistent with the numbers of IL-4-producing cells, C5-deficient mice also had increased bronchoalveolar lavage levels of the Th2 cytokines IL-5 and IL-13 and elevated serum levels of total and antigen-specific IgE. CONCLUSIONS: These data indicate that C5 plays an important protective role in allergic lung disease by suppressing inflammatory responses and Th2 effector functions observed in this experimental model. The protection provided by the presence of C5 is likely mediated by C5a, suggesting that C5a may play a significant role in tempering inflammation in Th2-driven diseases such as asthma.     

Distinct roles for IL-13 and IL-4 via IL-13 receptor alpha1 and the type II IL-4 receptor in asthma pathogenesis

IL-13 and IL-4 are central T helper 2 (Th2) cytokines in the immune system and potent activators of inflammatory responses and fibrosis during Th2 inflammation. Recent studies using Il13ra1(-/-) mice have demonstrated a critical role for IL-13 receptor (IL-13R) alpha1 in allergen-induced airway responses. However, these observations require further attention especially because IL-4 can induce similar lung pathology to IL-13, independent of IL-13, and is still present in the allergic lung. Thus, we hypothesized that IL-13Ralpha1 regulates IL-4-induced responses in the lung. To dissect the role of IL-13Ralpha1 and the type I and II IL-4Rs in experimental asthma, we examined lung pathology induced by allergen, IL-4, and IL-13 challenge in Il13ra1(-/-) mice. We report that IL-13Ralpha1 is essential for baseline IgE production, but Th2 and IgE responses to T cell-dependent antigens are IL-13Ralpha1-independent. Furthermore, we demonstrate that increased airway resistance, mucus, TGF-beta, and eotaxin(s) production, but not cellular infiltration, are critically dependent on IL-13Ralpha1. Surprisingly, our results identify a CCR3- and IL-13Ralpha1-independent pathway for lung eosinophilia. Global expression profiling of lungs from mice stimulated with allergen or IL-4 demonstrated that marker genes of alternatively activated macrophages are differentially regulated by the type I and type II IL-4R. Taken together, our data provide a comprehensive mechanistic analysis of the critical role by which IL-13Ralpha1 mediates allergic lung pathology and highlight unforeseen roles for the type II IL-4R.     

Mechanisms of IgE Inflammation

The prevalence of diseases such as allergic asthma and rhinitis continues to increase in the United States, affecting millions of people. It is well-established that allergy contributes to the pathogenesis of most asthma, especially in children and young adults. Despite current therapy (eg, inhaled corticosteroids, anti-leukotrienes, and bronchodilators), patients with moderate to severe asthma remain symptomatic and experience frequent exacerbations of disease requiring oral corticosteroids, emergency department treatments, and hospitalizations. Allergic diseases are traditionally referred to as immediate or type 1 hypersensitivity reactions, with IgE as a critical factor. IgE is involved in allergic inflammation, especially in early-phase response, but it may also be involved in the late-phase allergic response. A direct correlation between serum IgE levels and asthma exists. As logarithm IgE values increase, asthma prevalence increases linearly, even in patients who are categorized as having nonallergic asthma. In addition, there is a significant, although low association in allergic rhinitis with IgE levels and positive skin test reactivity to pollens. Recent advances in our understanding of the role of IgE in allergic inflammation have led to the development of a monoclonal antibody to IgE that reduces IgE levels, thereby reducing allergic inflammation. This review aims to provide an overview of the basic science of the IgE molecule and the clinical efficacy of anti-IgE therapy in allergic and asthmatic diseases.     

重组可诱导共刺激分子融合蛋白治疗过敏性支气管哮喘小鼠的实验研究

目的研究可诱导共刺激分子融合蛋白(ICOSIg)对过敏性支气管哮喘(简称哮喘)小鼠的治疗作用。方法32只健康雌性BALB/c小鼠用分段随机分组法将小鼠随机分成4组。哮喘组(A组)、ICOSIg治疗组(B组)、同型抗体对照组(C组)、生理盐水气雾激发对照组(D组),每组8只,采用重组真核表达技术制备ICOSIg,建立鸡卵白蛋白(OVA)免疫小鼠哮喘模型,给予ICOSIg治疗后观察其气道阻力变化、支气管肺泡灌洗液(BALF)中细胞总数、各炎性细胞百分比及白细胞介素4(IL4)、γ干扰素(IFNγ)和总免疫球蛋白E(IgE)含量的变化;采用流式细胞仪(FACS)检测T辅助细胞(Th)亚群变化;取肺组织行病理组织学分析观察肺内炎症情况。结果(1)制备的ICOSIg可与哮喘小鼠脾脏B细胞上相应配体结合。(2)B组小鼠气道压力变化为[(33±12)%],与A组[(58±10)%]比较差异有统计学意义(P<0.01)。B组BALF中细胞总数为[(5.9±3.1)×107/L],与A组[(22.6±5.3)×107/L]比较差异有统计学意义(P<0.01);B组嗜酸粒细胞数为0.020±0.020,与A组(0.070±0.030)比较差异有统计学意义(P<0.01);B组IL4水平为(77±31)ng/L,与A组[(179±44)ng/L]比较差异有统计学意义(P<0.01);B组外周血中总IgE水平为(175±33)μg/L,与A组[(282±22)μg/L]比较差异有统计学意义(P<0.01);B组Th2细胞比例为(4.5±1.0)%,与A组[(11.1±2.5)%]比较差异有统计学意义(P<0.01)。(3)与A组比较,B组小鼠肺内炎性浸润明显减轻、上皮细胞完整、管腔内少见分泌物。结论ICOSIg可体内阻断可诱导共刺激通路、减少Th2免疫反应偏移并抑制IgE的生成,对过敏性哮喘有治疗作用。     

过敏性哮喘青春期缓解者外周血IL—4、IL—5活性和IgE的变化

目的：阐明过敏性哮喘青春期解者血清IL－4及IL－5活性和IgE的变化，方法采用ELISA法检测IL－4、IL－5活性和IgE，分别对16例青春期缓解者（A组），26例哮喘发作期（B组）及22例哮喘缓解解患者（C组）和20例正常人（D组）进行比较。结果（1）青春期缓解者-5在性未显著升高，明显低于哮喘发作期患者（P＜0．01）和缓解期患者（P＜0．05），与正常人比较差异无显著性（P＞0．05）。（2）青春期缓解者IL－4较哮喘发作期患者明显降低（P＜0．01），与缓解期患者和正常人比较差异无显著性（P＞0．05）。（3）IgE浓度比较作期明显降低（P＜0．01），与政党人比较差异无显著性（P＞0．05），但还未明显低于哮喘缓解期患者（P＞0．05）。结论过敏性喘喘期解者外周血IL－4、IL－5活性明显降低，IgE有一定程度下降，提示IL－4、IL－5、IgE在支气管哮喘发病机制上起着重要作用。     

哮喘和慢性阻塞性肺疾病患者肺灌洗液Th亚群及B7分子的差异

目的探讨哮喘和慢性阻塞性肺疾病(COPD)及正常对照者支气管肺泡灌洗液(BALF)中淋巴细胞分泌γ干扰素(IFN-γ)、白细胞介素4(IL-4)水平和肺泡巨噬细胞(AM)表达C80(B7-1)、CD86(B7-2)共刺激分子百分率有何不同及其意义.方法分别对16名健康自愿者、16例过敏性哮喘患者和16例COPD患者进行了支气管肺泡灌洗(BAL),获取淋巴细胞和AM,用双抗体夹心酶联免疫吸附法(ELASA)测定了经植物血凝素(PHA)刺激培养的淋巴细胞上清液中IFN-γ和IL-4水平;用生物素-抗生物素复合物(ABC)夹心法测定了经脂多糖(LPS)剌激培养的AM膜表面表达CD80和CD86阳性率,并将正常对照组中已经LPS剌激的和未经LPS刺激的AM膜表面表达CD80与CD86阳性率进行对照.结果在反映Th2的IL-4水平,哮喘组为(331±150)ng/L,与正常对照组(106±42)ng/L及COPD组(49±20)ng/L比较,差异均有显著性(P均<0.01);COPD组IL-4水平与正常对照组比较,差异有显著性(P<0.01);在反映Th1的IFN-γ水平,COPD组(342±122)ng/L与正常对照组(188±67)ng/L及哮喘组(77±32)ng/L比较,差异也均有显著性(P均<0.01);哮喘组IFN-γ水平与正常对照组比较,差异有显著性(P<0.01).AM表达CD86阳性率哮喘组为(22±8)%,与正常对照组(12±6)%及COPD组(11±6)%比较,差异均有显著性(P均<0.01);COPD组与正常对照组比较差异无显著性(P>0.05);正常对照组中未经LPS刺激的与已经LPS刺激的AM在表达B7百分率上差异无显著性(P>0.05).三组48例受检者IL-4水平与经LPS刺激的AM表达CD86阳性率呈显著正相关(r=0.61,P<0.05).结论哮喘和COPD患者肺内淋巴细胞在细胞因子分泌谱上存在截然相反的格局,前者存在向Th2而后者存在向Th1极化的调控,其差异可能与抗原提呈细胞提供的共刺激信号不同有关,CD86在哮喘向Th2极化中可能起重要调控作用,这提示哮喘与COPD在肺局部细胞免疫学上无论从抗原提呈方式还是T细胞分泌谱上都是本质不同的两种疾病.     

Effects of antisense interleukin-5 gene transferred by recombinant adeno-associated virus to allergic rats

Background and objective: The accumulation of eosinophils in airways is an important characteristic of asthma. The process is primarily mediated by interleukin‐5 (IL‐5) secreted by Th2 lymphocytes. This study explored a new approach to asthma therapy in which allergic rats were transfected with the IL‐5 antisense gene delivered by the recombinant adeno‐associated virus (rAAV‐ASIL‐5). Methods: The viral vector rAAV‐ASIL‐5 was constructed and the IL‐5 antisense gene transfected into allergic rats. The levels of IL‐5, IgE, eotaxin and eosinophilic cationic protein (ECP) in sera and bronchoalveolar lavage fluid (BALF) were measured by ELISA. The inflammatory responses in lung tissues were evaluated by histological study. Results: The levels of IL‐5 protein in serum and BALF were significantly decreased in the allergic rats treated with rAAV‐ASIL‐5 (P < 0.05). Serum ovalbumin‐specific IgE was reduced in treated rats compared with untreated rats (P < 0.05). rAAV‐ASIL‐5 treatment also reduced eosinophils in the peripheral blood and BALF, as well as the ECP and eotaxin levels in serum and BALF (P < 0.05). There was significantly less inflammation in the lungs of rAAV‐ASIL‐5‐treated rats than in those of untreated rats. No obvious pathological damage to the kidneys and livers of the rats treated with rAAV was observed. Conclusions: Treatment with rAAV‐ASIL‐5 inhibited the accumulation of eosinophils and airway inflammation in the rat model of allergic asthma by suppressing IL‐5 production. These results suggest that rAAV‐ASIL‐5‐based gene therapy may be used for the treatment of allergic asthma.     

Heligmosomoides polygyrus infection down-regulates eotaxin concentration and CCR3 expression on lung eosinophils in murine allergic pulmonary inflammation

There is growing evidence that helminth infections might suppress allergic responses by mechanisms potentially involving regulatory T lymphocytes, cytokines, helminth molecules and polyclonal IgE. Heligmosomoides polygyrus infection in mice is associated with reduced local and systemic immune responses, thus providing an excellent model to study the mechanisms of immune regulation. In this research, we examined the way that nematode infection modulates the influx of eosinophils into the airways of asthmatic mice. We observed a reduction in the total number and percentage of lung eosinophils that coincided with decreased levels of eotaxin in bronchoalveolar lavage fluid (BALF), lower expression of the CCR3 receptor on eosinophils and impaired chemotaxis of these cells toward eotaxin. We conclude that allergen-induced immune response was down-regulated as production of Th1 (IFN-gamma)-, Th2 (IL-4, IL-5)- and Treg (IL-10)-related cytokines as well as IL-6 and TNF-alpha was diminished upon nematode infection. We postulate that attenuation of allergic inflammation during H. polygyrus infection is a consequence of the dichotomy of the immune response in the face of concurrent antigenic challenge.     

屋尘螨过敏原质粒DNA疫苗对屋尘螨小鼠气道变应性炎症的作用

目的 探讨屋尘螨过敏原质粒DNA疫苗对屋尘螨致敏／激发小鼠气道变应性炎症的作用。方法 40只小鼠分为健康对照组、屋尘螨致敏／激发模型组（用屋尘螨提取液致敏／激发）、Der p1治疗组（用屋尘螨提取液致敏／激发,用编码有屋尘螨过敏原Der p1的真核表达质粒肌肉注射后再次激发）、Der p2治疗组（用屋尘螨提取液致敏／激发,用编码有屋尘螨过敏原Der p2的真核表达质粒肌肉注射后再次激发）、Der p1联合Der p2治疗组（用屋尘螨提取液致敏／激发,用编码有屋尘螨过敏原Der p1和Der p2的真核表达质粒肌肉注射后再次激发）5组,每组8只。检测5组小鼠支气管肺泡灌洗液（BALF）中细胞计数和分类。取5组小鼠肺组织行病理检查。测BALF、血清中IL-4、IL-5、IFNγ／水平及BALF中IgE、IgG1水平。结果 屋尘螨致敏／激发模型组小鼠肺组织可见明显炎性细胞浸润;BALF中炎性细胞特别是嗜酸性粒细胞计数较健康对照组明显升高（P〈0．01）,IL-4、IL-5、IgE、IgG1水平较健康对照组明显升高（P〈0．001）,IFNγ／水平与健康对照组比较差异无统计学意义（P〈0．01）。经DNA疫苗治疗后,小鼠肺部炎性细胞浸润显著减少;BALF中炎性细胞计数及IL-4、IL-5、IgE、IgG1水平显著下降,IFNγ／水平无显著变化,IL-10水平显著升高。Der p1联合Der p2治疗组各项指标的改善情况优于Der p1治疗组和Der p2治疗组。结论 屋尘螨过敏原质粒DNA疫苗可有效抑制屋尘螨致敏／激发小鼠气道变应性炎症,且两种疫苗联合治疗优于单用一种疫苗治疗。     

Interleukin-4 is involved in allergen-induced airway eosinophilic inflammation and bronchial hyperresponsiveness independent of genetic background

The role of interleukin (IL)-4 in the development of allergen-induced airway inflammation and bronchial hyperresponsiveness (BHR) is still controversial. To investigate the role of IL-4 in the development of antigen-induced airway inflammation and BHR, we used two different inbred IL-4 gene-knockout mice; one was BALB/c, which is known to be a high IgE responder, and the other was C57BL/6, known to be a low IgE responder and a lower responder to acetylcholine (ACh) in the airways. Mice were immunized with antigen at intervals of 12 days. Starting 10 days after the second immunization, mice were exposed to antigen three times every fourth day. Twenty-four hours after the last antigen challenge, bronchial responsiveness to ACh was measured and bronchoalveolar lavage was performed. In sensitized BALB/c mice, repeated aeroallergen challenge induced dramatic eosinophilia in the airways and severe increases in bronchial responsiveness to intravenous ACh, along with increases in serum antigen-specific IgE. In contrast, immunized C57BL/6 mice, after antigen provocation, developed a minor influx of eosinophils into the airways and only moderate increases in bronchial responsiveness without antigen-specific IgE in serum, indicating that the genetic background influenced not only IgE synthesis, but also the degree of airway inflammation and BHR. Moreover, disruption of the IL-4 gene in both strains of mice abolished allergen-induced BHR, airway eosinophilia and IgE response. Together, these findings suggest that the differences in genetic background can directly influence the pathophysiology of bronchial asthma, including the role of IgE, and that IL-4 has a crucial role in the development of allergen-induced BHR independent of genetic background.     

南蛇藤素对哮喘小鼠TSLP介导的Th2优势免疫干预的研究

目的观察南蛇藤素对小鼠哮喘模型胸腺基质淋巴生成素(TSLP)介导的气道炎症的影响及机制。方法 24只SPF级BALB/c雌性小鼠随机分成4组。哮喘组、甲强龙组及南蛇藤素组分别予OVA致敏,然后腹腔注射等体积药物(分别为生理盐水、甲强龙及南蛇藤素),再予以雾化吸入1%OVA激发。对照组使用等剂量生理盐水。末次激发24h后,检测各组小鼠血清总Ig E及TSLP含量,支气管肺泡灌洗液(BALF)中IL-4、IL-13水平,HE染色肺组织病理学检测炎症浸润。结果南蛇藤素组小鼠哮喘表现较哮喘组明显改善;其血清总Ig E、TSLP含量及BALF中IL-4、IL-13水平均低于哮喘组(P0.05);且小鼠肺组织气道炎症明显减轻,但与甲强龙组无异(P0.05)。结论南蛇藤素组可以通过抑制哮喘小鼠TSLP介导的Th2优势免疫改善其临床症状。     

Elevated total serum immunoglobulin E (>1000 IU/mL): implications?

Atopic eczema, allergic broncho‐pulmonary aspergillosis, helminthic infections and rare primary immunodeficiencies are known to elevate total serum immunoglobulin E (IgE) above 1000 IU/mL. However, of 352 patients with IgE >1000 IU/mL seen in our hospital over a 5‐year period, less than 50% had these conditions. Markedly elevated IgE levels in the rest of the patients were associated with asthma, allergic rhinitis and food allergy, instances where the test is of limited diagnostic utility.     

Novel recombinant interleukin-13 peptide-based vaccine reduces airway allergic inflammatory responses in mice

RATIONALE: Interleukin (IL)-13 plays a pivotal role in the pathogenesis of allergic asthma. Passive administration of its monoclonal antibody or soluble receptor to block overproduced IL-13 has been proven to be effective in controlling airway allergic responses in animal models, but these approaches have disadvantages of short half-lives, high costs, and possible adverse effects. OBJECTIVES: We sought to develop a novel therapeutic strategy through constructing an IL-13 peptide-based vaccine for blocking IL-13 on a persistent effect basis and to evaluate its in vivo effects using a murine model. METHODS: To break self-tolerance, truncated hepatitis B core antigen was used as a carrier. Vaccine was prepared by inserting a peptide derived from the receptor binding site of mouse IL-13 into the immunodominant epitope region of the carrier using gene recombination methods. Mice received vaccine subcutaneously three times, and then subjected to intraperitoneal sensitization and intranasal challenge with ovalbumin. Control animals received carrier or saline in place of vaccine. MEASUREMENTS AND MAIN RESULTS: The vaccine presented as virus-like particles and induced sustained and high titered IL-13-specific IgG without the use of conventional adjuvant. Vaccination significantly suppressed ovalbumin-induced inflammatory cell number, and IL-13 and IL-5 levels in bronchoalveolar lavage fluids. Serum total and ovalbumin-specific IgE were also significantly inhibited. Moreover, allergen-induced goblet cell hyperplasia, lung tissue inflammatory cell infiltration, and pulmonary hyperresponsiveness to inhaled methacholine were significantly suppressed in vaccinated mice. CONCLUSIONS: Our data indicate that IL-13 peptide-based vaccines could be an effective therapeutic approach in the treatment of asthma.     

Augmentation of allergic inflammation in the airways of cyclooxygenase-2-deficient mice

OBJECTIVE: Airway cyclooxygenase-2 (COX-2) is induced by cytokine-mediated inflammation such as occurs in asthma. However, the role of COX-2 in the pathophysiology of asthma is not fully understood. METHODS: Allergic inflammation, airway responsiveness to methacholine and mucous cell metaplasia after ovalbumin sensitization in the airways of COX-2 deficient (-/-) mice, COX-2 (+/+) mice and C57BL/6J mice treated with a selective COX-2 inhibitor, nimesulide were assessed. Histology, cell analysis, measurements of arachidonic acid metabolites and Th2 cytokine levels in bronchoalveolar lavage fluid (BALF), and measurement of serum IgE were performed. RESULTS: Eosinophil infiltration into the airway wall, and the number of eosinophils in BALF were greater in sensitized COX-2 (-/-) mice than in sensitized COX-2 (+/+) mice. The levels of cysteinyl leukotrienes (LTC4/D4/E4), prostaglandin E2 (PGE2) and interleukin (IL)-13 as well as airway responsiveness did not differ in COX-2 (-/-) mice and COX-2 (+/+) mice. However, sensitized COX-2 (-/-) mice had higher LTC4/D4/E4 and lower PGE2 concentrations compared with non-sensitized COX-2 (-/-) mice. The number of PAS/alcian blue-positive airway epithelial cells and serum IgE were elevated in COX-2 (-/-) mice. Nimesulide-treated mice showed augmented eosinophilic inflammation, LTC4/D4/E4 concentrations and mucous cell metaplasia. CONCLUSION: These data indicate that COX-2 deficiency augments allergic inflammation and mucous cell metaplasia.     

Prevention of IL-6 signaling ameliorates toluene diisocyanate-induced steroid-resistant asthma

BackgroundAccumulating evidence indicated the crucial role for interleukin 6 (IL-6) signaling in the development of allergic asthma. Yet, the role of IL-6 signaling in toluene diisocyanate (TDI)-induced mixed granulocytic airway inflammation still remains unclear. Thus, the aims of this study were to dissect the role of IL-6 signaling and to evaluate the effect of tocilizumab on TDI-induced steroid-resistant asthma.MethodsTDI-induced asthma model was prepared and asthmatic mice were respectively given IL-6 monoclonal antibody, IL-6R monoclonal antibody (tocilizumab, 5 mg/kg, i.p. after each challenge) for therapeutic purposes or isotype IgG as control.ResultsTDI exposure just elevated IL-6R expression in the infiltrated inflammatory cells around the airway, but increased glycoprotein 130 expression in the whole lung, especially in bronchial epithelium. Moreover, TDI inhalation increased airway hyperresponsiveness (AHR) to methacholine, coupled with mixed granulocytic inflammation, exaggerated epithelial denudation, airway smooth muscle thickening, goblet cell metaplasia, extensive submucosal collagen deposition, dysregulated Th2/Th17 responses, as well as innate immune responses and raised serum IgE. And almost all these responses except for raised serum IgE were markedly ameliorated by the administration of IL-6 neutralizing antibody or tocilizumab, but exhibited poor response to systemic steroid treatment. Also, TDI challenge induced nucleocytoplasm translocation of HMGB1 and promoted its release in the BALF, as well as elevated lung level of STAT3 phosphorylation, which were inhibited by anti-IL-6 and anti-IL-6R treatment.ConclusionsOur data suggested that IL-6 monoclonal antibody and tocilizumab might effectively abrogate TDI-induced airway inflammation and remodeling, which could be used as a clinical potential therapy for patients with severe asthma.     

白细胞介素12重组腺病毒气道内应用对哮喘豚鼠治疗作用的研究

目的　探讨激发前气道内应用白细胞介素 12 (IL 12 )重组腺病毒对过敏性气道高反应的调节作用。方法　以C5 7BL/ 6小鼠经鸡卵蛋白 (OVA)免疫建立哮喘模型 ,实验分 6组 ,每组 6只。激发前气管内单次使用IL 12重组腺病毒 (10 8pfu/mouse) ,观察抗原激发后反应的变化。结果　 (1)小鼠气道内应用IL 12重组腺病毒在肺内可有效表达 ,48h血浆及肺泡灌洗液IL 12分别为 (5 40± 6 0 )U/ml和 (470 0± 80 0 )U/ml,对照病毒和PBS组未检出 ,两组比较差异有显著性 (P <0 0 1)。 (2 )在抗原激发阶段使用IL 12重组腺病毒 ,可明显抑制肺内IL 4[(3 5± 2 0 )ng/ml∶85 0± 2 5 0 )ng/ml]和IL 5[(6 5± 4 5 )ng/ml∶(5 4 0± 14 0 )ng/ml];γ干扰素 (IFN γ)的产生增加 [(6 90 0± 32 0 )ng/ml∶(12 5±3 2 )ng/ml];并明显抑制气道高反应性 [(36 0± 30 )cmH2 O∶(810± 5 0 )cmH2 O];抑制外周血 [(0 7±0 1) %∶(9 2± 0 5 ) % ]及肺泡灌洗液 [(3 5± 0 7)∶(2 1 6± 4 7)× 10 4 /ml]中的嗜酸细胞的水平 ;与对照组比较 (t分别 =7 97、7 92、5 1 6、18 9、9 33、47 1,P均 <0 0 1) ;但与总IgE[(6 5± 9) μg/ml∶(6 7± 10 )μg/ml]及抗原特异性IgE[(32± 8)∶(33± 8)U/ml]比较无明显影响 (P均 >0 0 5 )。