Effects of interleukin-18 on asthmatic airway inflammation and nuclear fa ctor kappa-B in murine models

Objective To investigate the effects of Interleukin-18 (IL-18) on asthmatic airway infla mmation and nuclear factor kappa-B (NF-κB) in a murine asthmatic model. Methods BALB/C mice were randomly divided into three groups: group A(control group,n=10) ; group B (asthmatic model group, n=10); group C (IL-18 injection group, n=10) . The asthmatic model was established in group B and C by respiratory syncytial virus (RSV) killed by ultraviolet light. Saline solution (0.1 ml) and IL-18 (0.1 ml, 1 μg) was injected in groups B and C at seven time points (1, 2, 7, 8 , 9, 21, 22 d). The symptoms and the numbers of eosinophils and plasmacytes in the airways were observed and the expression of NF-κB activation in the lung w as analyzed by Immohistochemistry (IHC) and Western blot. Results The symtoms of group C were more severe than in groups A and B. Group A did no t have EOS and plasmacytes in the airway submucosal while the numbers of eosinop hils ［15±3 (average cell counts per microscopic visual field, the same below) ］ and plasmacytes (10±2) in group B were found to have increased significantly . But the numbers of eosinophils and plasmacytes in group C were decreased sig nificantly when compared with group B (6±2 and 2±1, respectively, both P<0 .05). ISH showed that the expression of NF-κB activation in group B was stro nger than that in groups A and C. The amount of NF-κB inhibitor (IκB) in gro up A and group C were 3.5 times and 2.5 times more than that of group B respec tively via Western blot. Conclusion IL-18 can inhibit asthmatic airway inflammation in mice and its mechamism may b e due to the fact that IL-18 can inhibit the activation of NF-κB in the murin e asthmatic model.     

Increased Expression of PI-3K in Asthmatic Rat T Lymphocytes

In order to explore the expression of PI-3K in T lymphocytes of asthmatic rats and the relationship between PI-3K and activation of T lymphocytes, 24 Wistar rats were randomly divided into 4 groups: normal control group, asthmatic one-week group, asthmatic two-week group and asth-matic four-week group. T cells were purified from blood of each rat and the expression of PI-3K was observed by immunocytochemical fluorescence staining, the semiquantitative fluorescence intensity was measured by HPIAS-2000 analytic software, and the expression of IL-4 in supernatants was de-tected by ELISA. The results showed that the fluorescence intensity of T lymphocytes in asthmatic groups was significantly higher than that in normal control (P<0.001), indicating that the expression of PI-3K in T lymphocytes of asthmatic rats was significantly higher than that in those of normal controls, and the difference between acute and chronic stage asthmatic groups was significant (P<0.05). The expression levels of IL-4 protein in supernatants of asthmatic T lymphocytes were sig-nificantly higher than those in the normal controls (P<0.05). There was a significant positive correla-tion between the expression of PI-3K in T lymphocytes and the IL-4 protein expression in super-natants (r=0.583, P<0.01). It was suggested that PI-3K signal pathway may participate in the proc-esses of activation and other cytological effects of asthmatic T lymphocytes, thus may play an impor-tant roles in the pathogenesis of asthma.     

Activation and coreceptor expression of T lymphocytes induced by highly active antiretroviral therapy in Chinese HIV/AIDS patients

Background At the end of 2005, 650 000 people lived with human immunodeficiency virus type-1 (HIV-1) in China, of whom 75 000 were AIDS patients. Many AIDS patients received highly active antiretroviral therapy (HAART) supported by the “China CARES” program but the immune responses of HAART were seldom reported. This study investigated the effect of HAART on the activation and coreceptor expression of T lymphocytes in Chinese HIV/AIDS patients and evaluated its effect on immune reconstitution. Methods Seventeen HIV/AIDS patients were enrolled and three-color-flow cytometry was used to detect the activation of HLA-DR CD38 and the coreceptor CCR5, CXCR4 expression on T lymphocytes in whole blood samples taken from the patients before and after 3- or 6-month HAART.Results The activation percents of CD4(+), CD8(+) T lymphocytes were significantly higher before therapy than the normal controls (HLA-DR/CD4: 40.47±18.85 vs 11.54±4.10; CD38/CD4: 81.34±10.86 vs 53.34±11.44; HLA-DR/CD8: 63.94±12.71 vs 25.67±9.18; CD38/CD8: 86.56±11.41 vs 58.84±6.16, all P&lt;0.01). After 6-month combined antiretroviral treatment, the activation of T lymphocytes in HIV/AIDS patients was significantly decreased (HLA-DR/CD4: 28.31±13.48; CD38/CD4: 69.88±12.64; HLA-DR/CD8: 46.56±18.64; CD38/CD8: 70.17±14.54, all P&lt;0.01 compared with the pre-treatment values). Before the treatment, CCR5 expression on CD8(+) T lymphocytes was up-regulated while CXCR4 expression on CD8(+) T lymphocytes downregulated in HIV/AIDS patients compared with the normal controls (CD8/CCR5: 70.91±10.03 vs 52.70±7.68; CD8/CXCR4: 24.14±11.08 vs 50.05±11.68, all P&lt;0.01). After 6-month HAART, CCR5 expression on CD8(+) T lymphocytes significantly decreased (56.35±12.96, P&lt;0.01), while CXCR4 expression on CD8(+) T lymphocytes increased (36.95±9.96, P&lt;0.05) compared with the pre-treatment and the normal controls. A significant statistical relationship was observed between the expression of activation markers, CCR5 and the CD4(+) T lymphocyte counts after HAART (P&lt;0.05).Conclusions Reduced activation of T lymphocytes and a normalization of coreceptor expression were observed in Chinese HIV/AIDS patients after HAART. Immunity can be restored in HIV/AIDS patients receiving HAART.     

T helper cells in patients with chronic hepatitis B virus infection

Objective To investigate the compositions of Th1/Th2/Th3 cells in chronic hepatitis B viru s (HBV)- infected individuals by determining the expression of interleukin- 4 (I L- 4), inetrferon-γ (IFN-γ), and transform growth factor-β (TGF- β) in si ngle CD4(+)T cells isolated from peripheral blood mononuclear cells (PBMCs) and the role of polarized Th cell populations in chronic HBV- infection was discuss ed. Methods PBMCs from chronically infected HBV individuals were isolated, stimulated by PMA /Ionomycin/Monensin, and IL- 4, IFN-γ and TGF-β production by CD4(+)T cells was determined by using fluorescence activated cell sorter (FACS) analysis. Results The percentage of IFN- γ- producing T cells, IL- 4- producing T cells and TGF- β- producing T cells ranged from 2. 3%-18. 6%, 1. 1%-8. 7% and 0. 7%-7. 1% resp ectively in CD4(+) T cells from non- infected individuals. Most of CD4(+)T cel ls from PBMCs in chronically infected HBV individuals were Th0 cells. The propo rtion of Th1 cells increased significantly with hepatic inflammatory activity, and in the active period of chronic hepatitis B infection were higher than those in the non- active period (P&lt;0. 05). Th2 cell percentage in CD4(+)T c ells from HBV- infected individuals did not differ significantly (P&gt;0. 05), but were higher than that from controls (P&lt;0. 05). Th3 cell percentage in CD4(+) T cells from asymptomatic carrier (AsC) group was higher than that in the chronic hepatitis B (CHB) and control groups (P&lt;0. 05). Conclusions Th1 phenotype cytokines were positively correlated with hepatic inflammatory act ivity in chronic hepatitis B and Th2 cells may be associated with the persistenc e of HBV infection. Th3 cells cooperating with Th2 cells can negatively regulat e immune responses and may be associated with the immune tolerant state of chron ic HBV infection.     

Expression of NF-κB in hRPE Cells Stimulated by PDTC and IL-1β

The constitutive expression of nuclear-factor-κB (NF-κB) in human pigment epithelial (hRPE) cells cultivated in vitro and the possible changes when incubated with PDTC and IL-I were investigated. The synchronized hRPE cells in vitro were divided into two groups. In nonPDTC group, hRPE cells were exposed respectively to IL-1β and NS (for detecting the constitutive expressions of NF-κB in hRPE cells) ; In PDTC group, PDTC-pretreated hRPE cells were exposed respectively to IL-1β?Aand NS. (for detecting the constitutive expression of NF-κB in PDTC-pretreated hRPE cells). The expression of NF-κB in hRPE cells in two groups was detected by immunofluorescence stain and flow cytometry. The results showed that the constitutive expression of NF-κB in hRPE cells in vitro was 8.05 %, and increased to 30.26 % by IL-1β. After PDTC pretreatment, the constitutive expression of NF-κB in hRPE cells was decreased to 3.74%, and 3.66 % by IL-l,respectively. It was concluded that the expressions of NF-κB in hRPE cells could be increased significantly by IL-1βand depressed effectively by PDTC. Also, PDTC could significantly inhibit the activation of NF-κB induced by IL-1β.     

Ursolic Acid Inhibits T-Cell Activation through Modulating Nuclear Factor-κB Signaling

<正>Objective:To investigate the effects of ursolic acid(UA) on T-cell proliferation and activation,as well as to examine its effect on nuclear factor-κB(NF-κB) signaling pathway in T cells.Methods:T-cells isolated from BALB/c mice were incubated with UA at concentrations ranging from 5-30μmol/L in the presence of phorbol 12-myristate 13-acetate(PMA) or PMA plus ionomycin.The proliferation of T cells was measured by the MTT assay.The expressions of CD69,CD25,and CD71 on T-cell surface were analyzed using flow cytometry. The level of interleukin-2(IL-2) in the culture supernatant of activated T cells was quantified by enzyme-linked immunosorbent assay(ELISA).The level of phosphorylated IκB-α(p-lκB-α) in total protein and p65,a subunit of NF-κB,nuclear translocation were measured by Western blot analysis.Results:UA in a dose-dependent manner significantly decreased the proliferation and inhibited the surface expressions of CD69,CD25,and CD71 in murine T lymphocytes upon in vitro activation(P0.01).Significant reduction of IL-2 production was found in activated T cells treated with UA(P0.01).The PMA-induced increase in p-lκB-αprotein was inhibited,and nuclear translocation of p65 from the cytoplasm was blocked by UA.Conclusion:UA is a potent inhibitor for T cell activation and proliferation;these effects are associated with the inhibition of NF-κB signaling pathway.     

Activation of NF-κB in bronchial epithelial cells from children with asthma

Objectives To determine whether nuclear factor-κB (NF-κB) is activated in epithelial cells from children with asthma and to understand the role of NF-κB in airway inflammation in asthma. Methods Bronchial mucosa specimens were obtained from 9 children with asthma and 6 control subjects. NF-κB expression in epithelial cells were detected by immunohistochemical examination, and NF-κB-DNA binding was measured by electrophoretic mobility shift assay (EMSA). Results Nuclear expression of NF-κB in epithelial cells was observed in the 9 asthmatic children. NF-κB-DNA binding was found in 4 asthmatic children (EMSA was performed in 6 asthmatic children). In contrast, both nuclear expression and NF-κB-DNA binding were absent in the 6 control subjects. Conclusion These results indicated that NF-κB is activated in epithelial cells from asthmatic children and the NF-κB activation may be the basis for the increased expression of many inflammatory genes and for airway inflammation in asthma.     

Effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD34+ hematopoietic cells in bone marrow of asthmatic mice

Background Corticosteroids remain the most effective therapy available for asthma. They have widespread effects on asthmatic airway inflammation. However, little is known about the effects of corticosteroids on the production of bone marrow inflammatory cells in asthma. This study observed the effects of glucocorticoid and cysteinyl leukotriene 1 receptor antagonist on CD34+ hematopoietic cells, so as to explore the possible effectiveness of a bone marrow-targeted anti-inflammatory strategy. Methods Balb/c mice were sensitized and challenged with ovalbumin (OVA) to establish an asthmatic model. For two consecutive weeks, asthmatic mice were challenged with OVA while being given either prednisone, montelukast, prednisone plus montelukast, or sterile saline solution. The mice were killed 24 hours after the last challenge with OVA, and bronchoalveolar lavage fluid (BALF), peripheral blood, and bone marrow were collected. Eosinophils in peripheral blood and BALF, and nucleated cells in BALF, peripheral blood, and bone marrow were counted. The percentages of CD34+ cells, CD4+ T lymphocytes and CD8+ T lymphocytes among nucleated cells in peripheral blood and bone marrow were counted by flow cytometry. Immunocytochemistry and in situ hybridization were employed to detect expression of CD34 and interleukin (IL)-5Rα mRNA (CD34+ IL-5Rα mRNA+ cells) among bone marrow hematopoietic cells. Results Compared with the sterile saline solution group, the number of eosinophils in BALF and peripheral blood, CD34+ cells in peripheral blood and bone marrow, and CD34+ IL-5Rα mRNA+ cells in bone marrow of mice from the prednisone and prednisone plus montelukast groups were significantly lower （P&lt;0.01）. The number of eosinophils in BALF from the montelukast group was also significantly lower （P&lt;0.05）. Conclusions The results suggest that, in this asthmatic mouse model, prednisone probably inhibits proliferation, differentiation, and migration of CD34+ cells in bone marrow, blocks eosinophilopoiesis in bone marrow, and interferes with eosinophil migration into peripheral blood and subsequent recruitment in the airway. In addition, montelukast may suppress eosinophil infiltration into the lungs of asthmatic mice. However, a significant inhibitory effect of montelukast on the proliferation and migration of CD34+ cells and a cooperating effect with prednisone on bone marrow of asthmatic mice were not observed.     

An experimental study on the regulation of expression of Th2 cytokines from T lymphocytes by protein kinase C in asthma

Summary To explore the regulatory role of protein kinase C (PKC) in the expression of Th₂ cytokines, interleukin-4 (IL-4) and interleukin-5 (IL-5) by T lymphocytes in asthma. T lymphocytes were isolated and purified from blood and bronchial alveolus lavage fluid (BALF) of each guinea pig of normal control group and asthmatic group and from peripheral blood of the asthmatic patients and normal controls, and were stimulated with PKC accelerant phorbol 12-myristate 13-acetate (PMA) and inhibitor Ro31-8220. The expression of IL-4 and IL-5 mRNA and protein was detected by using in situ hybridization staining and ELISA respectively. The expression of IL-4 and IL-5 mRNA and protein of asthmatic T lymphocytes stimulated with PMA was significantly higher than that of asthmatic T lymphocytes stimulated without PMA respectively (P<0. 01) and that of normal T lymphocytes stimulated with PMA respectively (P<0. 01). The expression of IL-4 and IL-5 mRNA and protein of asthmatic T lymphocytes stimulated with PMA and Ro31-8220 was significantly lower than that of asthmatic T lymphocytes stimulated only with PMA respectively (P<0. 01). It was concluded that PKC might participate in regulating the expression of IL-4 and IL-5 in asthmatic T lymphocytes, and the activation of PKC in T lymphocytes might play an important role in the pathogenesis of asthma. This project was supported by a grant from National Natural Sciences foundation (No. 30070332) and Education Ministry college cadreman teachers imbursement plan (2000 year).     

An Experimental Study on the Regulation of Expression of Th_2 Cytokines from T Lymphocytes by Protein Kinase C in Asthma

Bronchial asthma (asthma) was a disease ofchronic airway inflammation.Inflammatory cells,primarily eosinophils and lymphocytes,andinflammatory proteins including cytokines generatedby them participated in pathogenesis of asthma.Interleukin- 4(IL- 4) and IL- 5 ,primarily generated bytype helper T lymphocytes(Th2 ) ,were consideredto be pivotal inflammation- promoting cytokines atpresent,and their expression was up- regulated inasthmatic process[1] ,but the idiographic regulatorymechanisms wer…     

The Effect of Ginkgo Biloba Extract on the Expression of PKCα in the Inflammatory Cells and the Level of IL-5 in Induced Sputum of Asthmatic Patients

To investigate the effect of the Ginkgo Biloba Extract (GBE) on the asthma and examine its possible mechanisms, 75 asthma patients were divided into 4 groups and the patients were respectively treated with fluticasone propionate for 2 weeks or 4 weeks, or treated with fluticasone propionate plus GBE for 2 weeks or 4 weeks. Fifteen healthy volunteers served as healthy controls. Sputum inhalation with inhaling hypertonic saline (4%-5%) was performed. Lung ventilatory function and forced expiratory volume in one second (FEV1) were measured. The numbers of different cells in induced sputum were calculated. The expression of PKCα in the cells was immunocytochemically detected and the percentages of positive cells in different cells were counted. Interleukin-5 (IL-5) in sputum supernatants was detected with enzyme-linked immunosorbent assay. The percentage of eosinophils, lymphocytes, PKCα positive inflammatory cells and the concentration of IL-5 in asthmatic patients were higher than those in the controls (P＜0.05), and the eosinophils, lymphocytes,positive expression of PKCα and the level of IL-5 were significantly decreased in asthmatic patients after they were treated with fluticasone propionate or fluticasone propionate plus GBE. However,they were still significantly higher than those of the controls. Compared to the group treated with glucocorticosteroid for 2 weeks, no significant decrease was found in the percentage of eosinophils,lymphocytes, PKCα positive inflammatory cells and the IL-5 in the supernatant of induced sputum.Compared with the group treated with glucocorticosteroid for 2 or 4 weeks, significant decrease in the same parameters was observed in the group treated with fluticasone propionate and GBE for 4 weeks. The IL-5 level in the supernatant of induced sputum was positively correlated with the percentage of PKCα-positive inflammatory cells and the percentage of eosinophils in the induced sputum in asthma patient groups respectively (n=150, r= 0.83, P＜0.01; n=150, r=0.76, P＜0.01). The FEV1 was negatively correlated with the percentage of PKCα-positive inflammatory cells and the IL-5 levels in supernatant of induced sputum in asthma patients respectively (n=150, r=-0.77,P＜0.01; n=150, r= -0.64, P＜0.01). It is concluded that GBE could significantly decrease the infiltration of inflammatory cells such as eosinophils and lymphocytes in the asthmatic airway and relieve the airway inflammation. GBE may decrease the activation of the PKCα in the inflammatory cells and thereby decrease the IL-5 level in induced sputum. GBE may be used as a complement to the glucocorticosteroid therapy for asthma.     

人外周血白介素-22产生细胞在不同淋巴细胞亚群中的比例

目的:采用流式细胞术(flow cytom etry,FCM)检测人外周血不同淋巴细胞亚群中白介素-22(IL-22)产生细胞的比例。方法:健康人外周全血用肝素抗凝管采集后与相同体积RPM I 1640培养液混匀,加入佛波酯和离子霉素,于37℃、5% CO₂静置培养2 h,再加入莫能霉素后继续培养4 h收集细胞。用荧光素标记单抗进行细胞表面抗原和胞内细胞因子染色,用FCM检测表达IL-22、IL-17的细胞在不同淋巴细胞亚群中的比例。结果:IL-22产生细胞在CD3+T细胞、CD4+T细胞、CD8+T细胞、自然杀伤(NK)细胞和B细胞的表达比例分别为1.83%、2.12%、0.67%、1.96%和1.09%,CD4+T细胞中的比例明显高于CD8+T细胞中的比例(P<0.01)。另外,在CD3+T细胞、CD4+T细胞和CD8+T细胞中,均检测到共表达IL-22和IL-17的细胞,差异有统计学意义(P<0.01)。结论:用FCM检测IL-22产生细胞在CD4+T细胞、CD8+T细胞、NK细胞和B细胞均有表达,在CD4+T细胞的比例明显高于CD8+T细胞。     

IL-17A抑制Th2细胞分化减轻哮喘小鼠气道嗜酸性粒细胞炎症

目的 研究IL-17A对哮喘小鼠Th2细胞分化及其相关炎症的作用.方法 24只C57BL/6J小鼠按随机数字表法分为对照组、哮喘组和IL-17A处理组(n=8).哮喘组和IL-17A处理组予以卵清蛋白(ovalbumin,OVA)致敏及激发.每次雾化激发前1h,IL-17A处理组给予重组小鼠IL-17A气道滴入.各步对照均予以生理盐水.末次激发后24h处死小鼠,收集支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)行细胞总数及分类计数.ELISA检测BALF中IL-4、IL-5、IFN-γ、IL-17A的浓度.HE和PAS染色及半定量评分评估小鼠肺部病理变化.流式细胞术检测脾脏和支气管淋巴结Th细胞分化.免疫磁珠分选健康小鼠幼稚CD4+T细胞,用Th2极化培养基体外培养,并给予IL-17A或等量PBS干预,检测Th2细胞的增殖、凋亡和分化.结果 哮喘组较对照组,BALF中细胞总数、嗜酸性粒细胞数及其比例(P＜0.05)、IL-4、IL-5、IL-17A浓度均显著增高(P＜0.05),IFN-γ浓度显著下降(P＜0.05);支气管、血管周围炎症细胞浸润和杯状细胞化生明显加重(P＜0.01);脾脏和淋巴结Th2细胞分化比例显著增高(P＜0.05).IL-17A处理组较哮喘组,BALF中的细胞总数[(26.00±5.43)×104/mLvs(58.40 ±26.93)×104/mL,P＜0.05]、嗜酸性粒细胞数[(8.04±1.98)×104/mL vs(31.95±12.28)×104/mL,P＜0.05]及其比例[(29.93 ±3.03)％ vs(53.47 ±6.62)％,P＜0.01]显著降低,而中性粒细胞数及其比例无明显变化;BALF中Th2相关因子IL-4浓度[(9.86 ±2.77) pg/mL vs(28.13 ±4.62) pg/mL,P＜0.01]、IL-5浓度[(7.30 ±0.50) pg/mL vs(10.50±1.10) pg/mL,P＜0.01]均显著降低;支气管、血管周围炎症细胞浸润减轻,HE染色半定量评分降低[(2.00 ±0.51)vs(3.12 ±0.64),P＜0.05],杯状细胞化生减少[(0.80 ±0.45)vs(2.40 ±0.55),P＜0.01];脾脏[(2.24±0.44)％vs(4.82±1.83)％,P＜0.01]和淋巴结[(7.05±0.58)％vs(10.57±1.35)％,P＜0.05]中Th2细胞分化比例显著减少.极化培养的幼稚CD4+T细胞,予IL-17A干预后,诱导分化的Th2细胞比例显著减少(P＜0.05),而增殖和凋亡无显著变化.结论 IL-17A有抑制Th2细胞分化,减轻哮喘小鼠气道嗜酸性粒细胞炎症的作用.