抗IgE抗体和腺苷对支气管哮喘患者肥大细胞激活的影响

肥大细胞只有激活才能在支气管哮喘 (简称哮喘 )发病过程中发挥作用 ,而组胺是肥大细胞激活后脱颗粒的主要标志物。据报道 ,细胞在缺氧或过度刺激等条件下代谢为腺苷[1] 。哮喘患者与非哮喘患者比较 ,其支气管肺泡灌洗液(ＢＡＬＦ)中腺苷水平增高[2 ] 。我们的实验用腺苷、抗ＩｇＥ抗体或两者联合应用对哮喘患者ＢＡＬＦ中的肥大细胞进行体外激发 ,通过测定组胺水平来探讨哮喘患者对肥大细胞的激活特征。对象与方法　腺苷、牛血清白蛋白、含 2 5ｍｍｏｌ/ＬＮ 2 羟乙基哌嗪 Ｎ′ 2 乙磺酸 (ＨＥＰＥＳ)的低限量Ｅａｇｌｅ培养液(ＭＥＭ)…     

小剂量茶碱调节哮喘患者T淋巴细胞的活性

目的 :观察茶碱对哮喘患者血清T淋巴细胞活性影响。方法 :检测哮喘患者每d给予茶碱控释片 4 0 0mg治疗 6周前后血清可溶性白细胞介素 2受体 (sIL 2R)浓度、T淋巴细胞亚群和IgE水平变化。结果 :哮喘患者经茶碱治疗 6周后其血清sIL 2R浓度显著下降 ,从治疗前 ( 0 31± 0 10 )U/L ,降低到治疗后 ( 0 2 5± 0 0 6 )U/L ,P <0 0 5。茶碱能显著提高哮喘患者外周血中的CD8T淋巴细胞数 (从治疗前的 18 9%± 4 4 %提高到治疗后的 2 5 8%± 5 9% ,P <0 0 5 ) ,同时CD4 /CD8%相应地显著降低 (P <0 0 5 )。茶碱并有降低哮喘患者外周血中IgE水平的趋势。结论 :小剂量茶碱能抑制哮喘患者血清T淋巴细胞活性 ,不仅具有抗炎作用 ,还有免疫调节作用 ,为评价茶碱在哮喘治疗中的作用提供了依据。     

支气管哮喘的药物治疗

支气管哮喘是由嗜酸性粒细胞、肥大细胞和T淋巴细胞等多种炎性细胞参与的气道慢性炎症。这种炎症使易感者对各种激发因子具有气道高反应性,并可引起气道缩窄,表现为反复发作性喘息、呼吸困难、胸闷或咳嗽等症状[1]。其诱发因素多种多样,有些机制尚不清楚,现就近年药物治疗进展综述如下。1茶碱类茶碱是常用的平喘药物,属于黄膘类衍生物,研究表明,除直接舒张平滑肌外,还具有抗炎作用[2]:(1)抑制IgE介导的肥大细胞释放组胺,通过提高人体内嗜酸粒细胞和肥大细胞内环磷腺苷(cAMP)的浓度而抑制其释放;(2)降低支气管哮喘患者呼吸道中白细胞介素4…     

特应性非哮喘患者吸入乙酰甲胆碱、AMP和致敏原后血浆的组织胺浓度

近来认为腺苷可能是一种支气管刺激物,间接引起支气管高反应性,因为有资料表明,它可通过增加气道内肥大细胞释放组织胺(组胺)而引起支气管收缩。本文为进一步研究 AMP(5′-磷酸腺苷)刺激肥大细胞释放组胺的作用,测定了吸入乙酰甲胆碱、AMP 和10种致敏物质后外周血组胺浓度。上述物质吸入的浓度可最大限度地使 FEV_1分别下降42.8±2.2%、46.5±3.9%和40.9±4.6%。平均血浆组胺浓度的基值分     

自身免疫性慢性荨麻疹的诊治

慢性荨麻疹(CU)的病因尚未完全阐明,其可能的因素涉及变态反应、假变态反应、慢性感染和自身反应。高达30%～50%的CU出现针对FcεRI a链或IgE本身的自身抗体。这些存在于患者循环系统中的自身抗体可导致皮肤嗜碱性细胞和肥大细胞活化释放组胺并引起风团。因此,大部分慢性特发性荨麻疹(CIU)是内源性自身免疫引起的。不伴自身抗体的CU病因仍不清楚,最近的研究显示部分患者内源性嗜碱性细胞和肥大细胞功能缺陷,导致其组胺释放模式发生改变。CU的严重性和临床类型变化很大,治疗方案应个体化。     

虫源性IgE依赖组胺释放因子诱导致敏肥大细胞释放组胺的研究

目的 制备日本血吸虫和华支睾吸虫IgE依赖组胺释放因子重组蛋白rSjHRF和rCsHRF，并观察两者诱导大鼠致敏肥大细胞释放组胺的功能。 方法 分别克隆SjHRF和CsHRF基因完整编码序列，将重组质粒分别转化大肠埃希菌BL21并诱导表达，亲和层析纯化可溶性表达的重组蛋白，将纯化的rSjHRF和rCsHRF分别与卵清蛋白变应原致敏的大鼠肺肥大细胞一起孵育，利用荧光分光光度法测定肥大细胞组胺释放量，并制备2种重组蛋白诱导肥大细胞释放组胺的剂量依赖曲线和动力学曲线。 结果 成功构建重组质粒pET?鄄30?鄄rSjHRF和pET?鄄30?鄄rCsHRF，并获得纯化的可溶性重组蛋白rSjHRF和rCsHRF；2种重组蛋白诱导大鼠致敏肥大细胞释放组胺均具有剂量依赖性，当浓度为150 mg/L时，rSjHRF和rCsHRF诱导致敏肥大细胞组胺平均释放率为49.78%和32.63%；2种重组蛋白诱导致敏肥大细胞组胺释放率随时间延长而增加，在反应开始后约35 min，组胺释放率达到最高。 结论 重组虫源性IgE依赖组胺释放因子可诱导大鼠致敏肥大细胞释放组胺，提示该蛋白可能与寄生性蠕虫感染诱导机体Ⅰ型超敏反应的发生相关。     

肥大细胞参与皮肤瘙痒的机制

肥大细胞长期定居在皮肤及黏膜中,是荨麻疹、食物过敏、哮喘、过敏性休克等变态反应疾病的主要效应细胞.肥大细胞参与的皮肤疾病大多表现为显著瘙痒.特异性IgE介导肥大细胞活化释放组胺进而引起神经敏化是瘙痒信号传递的经典神经免疫途径.近年来研究表明,除组胺外,肥大细胞释放其他炎症介质活化外周神经介导瘙痒信号传递也尤为重要.本文...     

雷公藤红素抑制支气管哮喘小鼠气道炎症的实验研究

目的　观察雷公藤红素对支气管哮喘 (简称哮喘 )小鼠气道炎症的抑制作用并探讨其作用机制。方法　 30只BALB/c小鼠按随机数字表法分为对照组 (A组 )、哮喘组 (B组 )、雷公藤红素治疗组 (C组 )。B组及C组以 10 %卵蛋白 (OVA)滴鼻复制哮喘模型 ,C组予以腹腔注射雷公藤红素 (1mg/kg)干预 ,观察肺组织病理学、支气管肺泡灌洗液 (BALF)中嗜酸粒细胞数目及肺组织干细胞因子(SCF)蛋白表达的变化。在体外实验中 ,建立C5 7B6小鼠骨髓来源的肥大细胞与成纤维细胞系NIH3T3的共培养体系 ,并予雷公藤红素 (2 μmol/L)干预 ,同时以单独培养的肥大细胞和NIH3T3细胞作对照 ;分别通过荧光测定法、酶联免疫吸附测定 (ELISA)、免疫组化染色检测各组上清液组胺、嗜酸粒细胞趋化因子 (eotaxin)含量及NIH3T3细胞中SCF的表达。结果　病理组织学显示 ,C组较B组小鼠肺组织炎性细胞浸润减少 ,C组BALF中的嗜酸粒细胞数为 (0 5 6± 0 0 3)× 10 6/L ,与B组 [(1 2 5±0 4 0 )× 10 6/L ]比较差异有显著性 (P <0 0 5 ) ;C组小鼠肺组织中SCF蛋白表达强度为 0 74± 0 2 0 ,与B组 (2 5 0± 0 19)比较差异有显著性 (P <0 0 1)。体外共培养体系中 ,上清液组胺、eotaxin含量及NIH3T3细胞的SCF蛋白阳性表达率分别为 (3 83± 0 4 1)n     

变应原激发后支气管肺泡灌洗液中特异性IgE增高

变应原与肥大细胞表面的IgE特异性结合,促进肥大细胞释放组胺和其他炎性介质,引发支气管哮喘,但IgE的合成是在全身还是在支气管粘膜局部仍不清楚。为此,对18例室尘螨和草花粉过敏的非吸烟哮喘患者进行了研究。 方法 对18例室尘螨和草花粉过敏的非吸烟哮喘患者,在变应原激发前和24时后分别进行支气管肺泡灌洗(BAL)。在两次BAL前均采取血标本。用自动荧光酶试验测定免疫球蛋白,用溴甲酚紫技术测定血清中的白蛋白含     

肥大细胞蛋白酶类在呼吸道中的作用

肥大细胞与哮喘和其它炎症性疾病有关。它释放的类胰蛋白酶和糜蛋白酶,在免疫性和炎症性呼吸道疾病中有重要的病理作用。①气道平滑肌收缩:纯化的肥大细胞瘤细胞与人和狗正常肥大细胞相似,钙离子载体 A23187可刺激其脱颗粒,释放类胰蛋白酶和糜蛋白酶.将这种激活后的上清液(已除去 A23187)加入肌槽中,可大大加强狗支气管平滑肌对组胺的     

Induction of tryptase and histmine release from human colon mast cells by IgE dependent or independent mechanisms

AIM: To investigate the tryptase and histamine release ability of human colon mast cells upon IgE dependent or independent activation and the potential mechanisms.METHODS: Enzymatically dispersed cells from human colons were challenged with anti-IgE or calcium ionophore A23187, and the cell supernatants after challenge were collected. Both concentration dependent and time course studies with anti-IgE or calcium ionophore A23187 were performed. Tryptase release was determined with a sandwich ELISA procedure and histamine release was measured usina a glass fibre-based fluorometric assay.RESULTS: Both anti-IgE and calcium ionophore were able to induce dose dependent release of histamine from colon mast cells with up to approximately 60% and 25% net histamine release being achieved with 1 μg/mL calcium ionophore and 10 μg/mL anti-IgE, respectively. Dose dependent release of tryptase was also observed with up to approximately 19 ng/mL and 21 ng/mL release of tryptase being achieved with 10 μg/mL anti-IgE and 1 μg/mL calcium ionophore, respectively. Time course study revealed that both tryptase and histamine release from colon mast cells stimulated by anti-IgE initiated within 10 sec and reached their maximum release at 6 min following challenge. Pretreatment of cells with metabolic inhibitors abolished the actions of anti-IgE as well as calcium ionophore. Tryptase and histamine release, particularly that induced by calcium ionophore was inhibited by pretreatment of cells with pertussis toxin.CONCLUSION: Both anti-IgE and calcium ionophore are able to induce significant release of tryptase and histamine from colon mast cells, indicating that this cell type is likely to contribute to the pathogenesis of colitis and other mast cell associated intestinal diseases.     

Induction of tryptase and histamine release from human colon mast cells by IgE dependent or independent mechanisms

AIM: To investigate the tryptase and histamine release ability of human colon mast cells upon IgE dependent or independent activation and the potential mechanisms.METHODS: Enzymatically dispersed cells from human colons were challenged with anti-IgE or calcium ionophore A23187, and the cell supernatants after challenge were collected. Both concentration dependent and time course studies with anti-IgE or calcium ionophore A23187 were performed. Tryptase release was determined with a sandwich ELISA procedure and histamine release was measured using a glass fibre-based fiuorometric assay.RESULTS:Both anti-IgE and calcium ionophore were able to induce dose dependent release of histamine from colon mast cells with up to approximately 60% and 25% net histamine release being achieved with 1μg/mL calcium ionophore and 10μg/mL anti-IgE, respectively. Dose dependent release of tryptase was also observed with up to approximately 19ng/mL and 21ng/mL release of tryptase being achieved with 10μg/mL anti-IgE and 1μg/mL calcium ionophore, respectively. Time course study revealed that both tryptase and histamine release from colon mast cells stimulated by anti-IgE initiated within 10 sec and reached their maximum release at 6 min following challenge. Pretreatment of cells with metabolic inhibitors abolished the actions of anti-IgE as well as calcium ionophore. Tryptase and histamine release, particularly that induced by calcium ionophore was inhibited by pretreatment of cells with pertussis toxin.CONCLUSION: Both anti-IgE and calcium ionophore are able to induce significant release of tryptase and histamine from colon mast cells, indicating that this cell type is likely to contribute to the pathogenesis of colitis and other mast cell associated intestinal diseases.     

The antineoplastic bryostatins affect human basophils and mast cells differently

Bryostatins, macrocyclic lactones from the marine bryozoan Bugula neritina, are potent antineoplastic agents and multi-potential stimulators of immune cells. We have examined the effects of bryostatins on mediator release from human basophilic leukocytes and human tissue mast cells. Bryostatins 1, 2, and 5 (10 to 3,000 nmol/L) induced histamine secretion from purified and unpurified peripheral blood basophils, whereas they caused no release of peptide-leukotriene C4 from these cells. The rate of histamine release caused by bryostatin 1 was slower than that caused by anti-IgE (t1/2 +/- SEM = 38.2 +/- 4.7 minutes v 8.9 +/- 0.2 minutes; P < .01), whereas the temperature dependence was similar (optimum release at 37 degrees C, approximately 30% less at 30 degrees C, and no release at 22 degrees C or 4 degrees C). The addition of increasing concentrations of extracellular Ca2+ to the medium caused histamine release in the presence of bryostatins. Subeffective concentrations of bryostatins and anti-IgE produced a synergistic effect on histamine release from basophils. Staurosporine, chelerythrine, and calphostin C (0.1 to 10 nmol/L), which are protein kinase C inhibitors, inhibited the histamine secretion activated by bryostatin 1 and tetradecanoylphorbol-acetate (TPA). Preincubation with granulocyte-monocyte colony-stimulating factor (GM-CSF; 1 and 5 nmol/L) and interleukin-3 (IL-3; 10 ng/mL) potentiated the activation of human basophils induced by bryostatin 1. Neither bryostatin 1 nor bryostatin 2 induced the release of histamine from mast cells isolated from human lung or skin tissues. However, brief (10 minutes) preincubation with bryostatin 1 (3 to 300 nmol/L) potently inhibited the histamine secretion induced by anti-IgE from skin or lung mast cells. Bryostatin 1 was a more potent (by approximately 30 times) inhibitor of IgE- mediated histamine release than was TPA. The heterogeneous effects exerted by bryostatins on human basophils and mast cells can be of interest for those designing therapeutic trials using these agents.     

Modulation of tryptase secretion from human colon mast cells by histamine

AIM: TOtryptasepotentialinvestigate the ability of histamine to modulate release from human colon mast cells and the mechanisms.METHODS: Enzymatically dispersed cells from human colons were challenged with histamine, anti-IgE or calcium ionophore A23187 (CI), and the cell supernatants after challenge were collected. Tryptase release was determined with a sandwich ELISA procedure.RESULTS:Histamine at concentrations from 1ng/mL was able to induce a “bell” shape dose related release of tryptase from colon mast cells. The maximum release of tryptase was approximately 3.5 fold more than spontaneous release. As little as 10ng/ml histamine showed a similar potency to 10μg/mL anti-IgE in induction of tryptase release. Histamine induced release of tryptase initiated at 10s when histamine (100ng/mL) was added to cells, gradually increased thereafter, and completed at 5 rain.Both pertussis toxin or metabolic inhibitors were able to inhibit histamine induced tryptase release. When histamine and anti-IgE were added to colon mast cells at the same time, the quantity of tryptase released was similar to that induced by anti-IgE alone.The similar results were observed with CI. However, when various concentrations of histamine were incubated with cells for 20min before adding anti-IgE or CI, the quantity of tryptase released was similar to that was induced by histamine alone.CONCLUSION:Histamine is a potent activator of human colon mast cells, which represents a novel and pivotal selfamplification mechanism of mast cell degranulation.     

Modulation of histamine release from human colon mast cells by protease inhibitors

AIM: To investigate the ability of protease inhibitors to modulate histamine release from human colon mast cells. METHODS: Enzymatically dispersed cells from human colon were challenged with anti-IgE or calcium ionophore A23187 in the absence or presence of tryptase and chymase inhibitors, and histamine release was determined. RESULTS: IgE dependent histamine release from colon mast cells was inhibited by up to approximately 37%, 26% and 36.8% by chymase inhibitors Z-Ile-Glu-Pro-Phe-CO2Me (ZIGPFM), N-Tosyl-L-phenylalanyl-chloromethyl ketone (TPCK), and alpha1-antitrypsin, respectively. Similarly, inhibitors of tryptase leupeptin, N-tosyl-L-lysine chloromethyl ketone (TLCK), lactoferrin and protamine were also able to inhibit anti-IgE induced histamine release by a maximum of some 48%, 37%, 40% and 34%, respectively. Preincubation of these inhibitors with cells for 20 min before challenged with anti-IgE had small effect on the inhibitory actions of these inhibitors on colon mast cells. A specific inhibitor of aminopeptidase amastatin had no effect on anti-IgE induced histamine release. The significant inhibition of calcium ionophore induced histamine release was also observed with the inhibitors of tryptase and chymase examined. Apart from leupeptin and protamine, the inhibitors tested by themselves did not stimulate colon mast cells. CONCLUSION: It was demonstrated that both tryptase and chymase inhibitors could inhibit IgE dependent and calcium ionophore induced histamine release from dispersed colon mast cells in a concentration dependent of manner, which suggest that they are likely to be developed as a novel class of anti-inflammatory drugs to treat chronic of colitis in man.     

Characterization and functional studies of rheumatoid synovial mast cells: Activation by secretagogues,anti-IgE,and a histamine-releasing lymphokine

Microscopic analysis of synovial specimens from 35 patients with rheumatoid arthritis (RA) and 7 patients with osteoarthritis revealed mast cell hyperplasia in perivascular regions, in fibrous interstitial areas, and clustered around the periphery of lymphoid aggregates. Metachromatic staining, immunofluorescence studies, and ultrastructural analysis revealed a single population of connective tissue-type mast cells with surface IgE receptors. Total extractable histamine of synovial tissue was 4.15 ± 2.30 μg/gm (n = 8) for RA synovium and 0.53 ± 0.23 μg/gm (n = 7) for OA synovium. Mast cell secretion was assessed and specific release of histamine from RA synovial mast cells was observed following stimulation with anti-IgE (32.3%), compound 48/80 (40.1%), calcium ionophore A23187 (25.2%), and a partially purified lymphokine with histamine-releasing activity (23.9%).     

Activation of pulmonary mast cells by bronchoalveolar allergen challenge. In vivo release of histamine and tryptase in atopic subjects with and without asthma

Human mast cells likely play a significant role in human asthma. In the present study, concentrations of tryptase and histamine in bronchoalveolar lavage fluid (BALF) were used as indicators of pulmonary mast cell activation. BALF was obtained before and after endobronchial allergen challenge and assessed for mediator content and cell composition in 4 subject groups: nonatopic nonasthmatics (Group 1, n = 7), nonatopic asthmatics (Group 2, n = 3), atopic nonasthmatics (Group 3, n = 7), and atopic asthmatics (Group 4, n = 7). Before challenge, histamine concentrations were not different between the 4 groups, whereas tryptase concentrations were significantly greater in the atopic asthmatics than in each of the other groups (p less than 0.04). Allergen challenge in atopic asthmatics resulted in significant increases above baseline in mean +/- SD histamine (0.7 +/- 7.1 to 2.8 +/- 2.0 ng/ml) and tryptase (2.0 +/- 1.7 to 10.1 +/- 8.2 ng/ml) concentrations in BALF (p less than 0.03). Atopic nonasthmatics also had increases above baseline in histamine (0.2 +/- 0.2 to 1.2 +/- 1.4 ng/ml) and tryptase (0.5 +/- 0.4 to 1.4 +/- 1.03 ng/ml) concentrations after allergen challenge (p less than 0.05). Though the histamine values were not significantly different between atopic nonasthmatics and atopic asthmatics after allergen challenge, tryptase concentrations were markedly higher in the atopic asthmatic group. The numbers, as well as the predominance of the T mast cell type in atopic asthmatics and nonasthmatics, were no different from controls. In nonatopic subjects, regardless of asthmatic state, histamine or tryptase concentrations were not altered by allergen challenge.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interaction between hyperosmolar and IgE-mediated histamine release from basophils and mast cells

Because both hyperosmolar and IgE-dependent stimuli may be encountered in the airway, and because hyperosmolarity causes histamine release in basophils, we examined the effects of the 2 stimuli on human lung mast cells. Mast cells prepared by enzymatic digestion of human lung were suspended in buffers made hyperosmolar with mannitol. Significant histamine release was seen above 360 mOsm/kg H2O, increasing to 11.9 +/- 1.0% at 770 mOsm/kg H2O, and release was synergistically enhanced by anti-IgE. Cells that had been rendered unresponsive to IgE-dependent stimuli by exposure to anti-IgE in the absence of Ca++ became markedly more responsive to hyperosmolar stimulation, and released as much as 32 +/- 2% histamine in hyperosmolar buffers alone. Antigen-induced histamine release from the basophils of allergic donors was also synergistically enhanced in buffers above 460 mOsm/kg H2O. These data show that immunologic and nonimmunologic stimuli may interact, and that human lung mast cells are capable of mediator release when exposed to osmolarities that may occur in the airway, especially during hyperventilation. Hyperosmolar mediator release is a plausible mechanism by which exercise-induced hyperventilation might induce asthma.     

Characterization of human synovial mast cells

Human synovium obtained at arthroplasty from patients with rheumatoid arthritis (RA) and osteoarthritis (OA) were characterized by assessing mast cell morphology, content and function. Histological studies confirmed significant numbers of mast cells in both RA and OA synovium. Electron microscopic data support the morphologic similarity between human synovial mast cells and human mast cells in lung and intestine. Likewise, synovial mast cells do not appear to be functionally different from pulmonary or intestinal mucosal mast cells. Mast cell suspensions with a cellular histamine content of 4.3 +/- 0.5 pg/cell (mean +/- SEM) released histamine following provocation with anti-IgE and calcium ionophore but not compound 48/80, f-met peptide or bradykinin. Prostaglandin D2 (PGD2) and leukotriene C4 (LTC4) were also released in response to anti-IgE. Auranofin inhibited anti-IgE provoked histamine, PGD2 and LTC4 release while gold sodium thiomalate, cromolyn and indomethacin had no effect on histamine release. Theophylline inhibited anti-IgE induced histamine release only at concentrations greater than or equal to 10(-3) M. Our study argues against functional or morphologic mast cell heterogeneity of human intestinal, lung and synovial origin and suggests that mast cells may have a pathogenic role in both RA and OA.     

Immunoglobulin E-mediated release of a kininogenase from purified human lung mast cells

Certain manifestations of the allergic response, such as vasodilation and edema, may be attributed to the involvement of kinins, but, as yet, little data exist to show how these peptides could be produced during IgE-mediated events. We now report that purified human lung mast cells contain a kininogenase that is released in a dose-dependent fashion by anti-IgE. Release of kinin-generating activity parallels that of histamine and, like histamine release, kininogenase release is temperature-dependent. Kininogenase release also parallels increasing histamine release when mast cells of increasing size are stimulated with an optimal level of anti-IgE. Finally, when mast cells of greater than 99% purity were optimally challenged, kininogenase activity again paralleled histamine levels in the release supernatant and residual cell pellet. The mast cell kininogenase appears to be a preformed mediator in that it occurs in lysates of unstimulated mast cells of greater than 99% purity. Optimal generation of kinin from highly purified human low molecular weight kininogen occurred at pH 5.5 and in 8 preparations was 380 +/- 237 ng kinin/h/10(6) mast cells (means +/- SD). Thus, human lung mast cells contain a kininogenase that is released during, and may participate in, IgE-mediated inflammatory disorders in humans.