重组人碱性成纤细胞生长因子单克隆抗体的制备、鉴定及初步应用

目的制备重组人碱性成纤维细胞生长因子(recombinant human basic fibroblast growth factor,rhbFGF)单克隆抗体,鉴定其特性,建立双抗体夹心ELISA检测方法。方法以rhbFGF为免疫原,免疫Balb/c小鼠,通过细胞融合技术建立能稳定分泌抗rhbFGF杂交瘤细胞株,制备抗rhbFGF单克隆抗体,采用Ig亚类ELISA试剂盒鉴定抗体亚类,间接ELISA法检测抗体效,Western blot鉴定抗体特异性。HRP标记McAb并建立夹心ELISA检测方法。结果获得2株(分别命名2D3、5F7)可分泌特异性McAb的强阳性细胞株,腹水抗体效价在10-5以上,IgG亚类均为IgG1,轻链为K链。Western blot证明2株McAb特异性良好,双抗体夹心ELISA检测rhbFGF最低检测限达到2 ng/ml。结论成功制备高效价的抗rhbFGF单克隆抗体,建立抗rhbFGF双抗体夹心ELISA定量检测方法。     

LAIR-2单克隆抗体的制备、鉴定和夹心ELISA方法的建立

为了制备LAIR 2单克隆抗体并建立夹心ELISA方法。应用淋巴细胞杂交瘤技术制备抗LAIR 2单克隆抗体 (mAb )。采用间接免疫荧光染色和流式细胞术鉴定LAIR 2的细胞分布。辣根过氧化物酶 (HRP )标记LAIR 2mAb ,并建立检测LAIR 2的夹心ELISA方法。用重导向杀伤实验 (RCA )鉴定LAIR分子参与调节杀伤功能的关系。结果成功地制备了 3株特异识别LAIR 2的mAb ,1株mAb (3G4 )能够识别LAIR 1和LAIR 2的共同表位 ,但不能在重导向杀伤实验中抑制CD16诱导的杀伤功能。夹心ELISA方法检测LAIR 2的敏感性为 5ng/ml,为LAIR 2的分布及定量检测提供了方法     

Pfs25蛋白单克隆抗体的制备及双抗体夹心ELISA的建立

目的:制备恶性疟原虫子孢子囊表面膜蛋白Pfs25的单克隆抗体( mAb),建立检测Pfs25蛋白的双抗体夹心ELISA方法.方法:纯化毕赤酵母表达的重组Pfs25蛋白,并免疫BALB/c小鼠,采用骨髓瘤细胞Sp2/0与免疫BALB/c鼠脾细胞杂交的细胞融合技术,通过间接ELISA检测获得分泌抗Pfs25抗体的阳性杂交瘤细胞株,通过免疫F1鼠诱生腹水,纯化腹水,并进行mAb的各项生物学鉴定.辣根过氧化物酶(HRP)标记纯化后的抗体,以4B7为包被抗体,1B4为酶标抗体,建立了双抗体夹心ELISA法.结果:获得3株抗Pfs25的杂交瘤细胞株,其中2株有良好的稳定性和特异性.并建立了双抗体夹心ELISA检测法,检测有效范围在0.07～1 mg/mL,其检测灵敏度为41.6 ng/mL.结论:成功制备抗Pfs25蛋白的单克隆抗体,并建立了一种可用于Pfs25蛋白检测的双抗体夹心ELISA法,为Pfs25蛋白制备传播阻断型疟疾疫苗奠定了基础.     

抗人NGAL单克隆抗体的制备及其定量检测方法的建立

目的获得抗人中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin,NGAL)特异性单克隆抗体并建立双抗体夹心ELISA免疫定量检测方法。方法通过杂交瘤技术制备了抗人NGAL高亲和力高特异性单克隆抗体,筛选能够结合天然NGAL的单克隆抗体并建立双抗体夹心ELISA系统。以重组人NGAL为检测对象,对系统线性范围、灵敏度、精密度和准确度(回收试验)进行全面分析和评价。通过对肾病患病组和对照组尿液标本检测初步研究其在临床上的分析性能。结果获得了8株能稳定分泌抗人NGAL单克隆抗体的杂交瘤细胞株,筛选得到F2和G2两株单克隆抗体可用于双抗夹心ELISA免疫检测。本方法线性范围为0～40 ng/ml,灵敏度为4.8 ng/ml,批内变异CV≤10.04%,批间变异CV≤9.76%,平均回收率为101.9%。临床标本检测显示肾病组与对照组有显著差异(P<0.01)。结论本研究制备了高亲和力特异性单克隆抗体并建立了双抗体夹心ELISA方法,该方法灵敏度、精密度和准确性良好,能够检测体液标本中的天然NGAL蛋白,检测结果与临床基本符合,为其临床应用和推广奠定了基础。     

麻痹性贝毒单克隆抗体的制备和酶联免疫检测方法的建立

目的:利用B淋巴细胞杂交瘤技术制备麻痹性贝毒(PSP)的单克隆抗体,以便建立快速、灵敏、有效的毒素检测方法.方法:采用甲醛法将半抗原石房蛤毒素(STX)与血蓝蛋白(KLH)偶联制备成完全抗原STX-KLH,免疫BALB/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞融合,经筛选和克隆,HAT选择培养杂交瘤细胞,利用ELISA方法筛选出分泌抗STX-McAB的杂交瘤细胞株,并通过小鼠体内诱生腹水的方法获得单克隆抗体.结果:共获得4株能稳定分泌麻痹性贝毒抗体的阳性细胞株,建立了分析检测麻痹性贝毒的间接竞争酶联免疫方法.对PSP中STX组分的检出限为20 ng/ml,IC50为220 ng/ml;对GTX2/3的检出限为10 ng/ml,IC5o为50 ng/ml.结论:所制备抗体具有高特异性和灵敏性,可用于研制高质量的国产快速检测麻痹性贝毒ELISA试剂盒.     

多种单抗联合检测HIV抗原

目的 建立多种单抗联合早期检测HIV抗原的夹心ELISA方法.方法 以SAS盐析沉淀法和亲和层析法纯化抗HIV-1 p24、gp41、gp120及抗HIV-2 gp36的腹水型单克隆抗体(McAb),用高碘酸钠法将纯化的McAb以HRP进行标记.建立针对单个抗原的双抗体夹心ELISA法,对其灵敏度及特异性进行检测.将筛选得到的4株捕获McAb按比例混合作为捕获抗体,4株酶标McAb按比例混合作为检测抗体,建立多种单抗联合检测HIV抗原的夹心ELISA方法,检测混合HIV抗原.结果 按确定的最优反应条件建立的多种McAb联合夹心ELISA方法,检测到的最高稀释度的HIV混合抗原中各抗原的终浓度分别为:重组HIV-1 p24:0.625 pg/ml,gp41:6.25 ng/ml,gp120:6.25 ng/ml;HIV-2 gp36:9.25 ng/ml.结论 建立了具有高度敏感性的鸡尾酒式多种单抗联合检测HIV抗原的夹心ELISA法,为早期榆测HIV抗原提供了新的思路,为后续的研究奠定了一定基础.     

石杉碱甲快速检测酶联免疫试剂盒的制备

目的:制备并鉴定石杉碱甲单克隆抗体,研制石杉碱甲间接竞争酶联免疫试剂盒。方法:以石杉碱甲人工抗原免疫BALB/c小鼠获得单克隆抗体,采用酶联免疫吸附法制备石杉碱甲试剂盒,对试剂盒各项指标进行评价。结果:试剂盒工作范围为5~2 500 ng/ml,检测限为6.242 ng/ml,与多种生物碱均无交叉反应,试剂盒可在4℃或-20℃下稳定贮存半年以上,石杉碱甲片回收率在94.2%~108.6%之间,变异系数在2.3%~4.8%之间。结论:石杉碱甲ELISA试剂盒快速、灵敏、稳定,可用于石杉碱甲的含量测定。     

抗烟曲霉菌单克隆抗体鉴定和初步应用

目的 :制备抗烟曲霉菌单克隆抗体 (McAb) ,建立一种快速检测烟曲霉菌抗原方法。方法 :用基因重组烟曲霉菌半乳糖甘蛋白 (AFMP1)抗原 ,免疫BALB/c小鼠 ,制备单克隆抗体 ,选择针对不同抗原决定簇单抗配对 ,建立双抗夹心ELISA法检测烟曲霉菌抗原。结果 :筛选出 3株稳定分泌抗烟曲霉菌单抗杂交瘤细胞株 ,IgG亚类鉴定分别为IgG1、IgG2a、IgG2b ,抗体亲和常数分别为 1 2× 10 10 、4 5 6× 10 9和 1 81× 10 10 mol/L ,免疫印迹证实单抗特异性识别烟曲霉菌培养上清和细胞裂解产物 ,相加试验表明 3株单抗是针对不同抗原决定簇 ,组成配对双抗夹心ELISA法 ,检测最高灵敏度为 0 1ng/ml,可测范围为 0 1～ 6 0ng/ml。结论 :3株杂交瘤细胞株特异性好、亲和力高 ,组成配对夹心ELISA法可用于快速检测烟曲霉菌抗原。     

自制NSE单抗的鉴定及其双抗夹心ELISA方法的建立

目的:制备并鉴定NSE(Neuron-specific enolase)单克隆抗体,建立可检测NSE蛋白的双抗夹心ELISA方法。方法:用本实验室已表达纯化的NSE融合蛋白免疫BALB/c小鼠,采用杂交瘤技术制备单克隆抗体。采用WB、IP、IF、IHC等方法对获得的NSE单抗进行鉴定及亚型检测。利用辣根过氧化物酶标记纯化后的NSE单抗,建立一个可检测NSE蛋白的双抗夹心ELISA法。结果:通过分析和鉴定,选定2株可稳定分泌抗NSE抗体的杂交瘤细胞株,效价达4.2×107～6.5×107,亚型为IgG2b。免疫印迹结果显示,该抗体不仅能识别细胞内源NSE蛋白,还能识别分泌到细胞培养上清液中的NSE蛋白,此外还可用于免疫荧光及免疫组化检测。文中所建立的双抗夹心ELISA法,最低检测极限为8.85 ng/ml。结论:成功获得了效价高、灵敏度好及特异性强的NSE单抗,建立了一个双抗体夹心ELISA检测系统,具有良好的临床应用前景。     

重组人源细胞珠蛋白单抗制备及检测方法建立

目的制备重组人源细胞珠蛋白（recombinanthumanCytoglobin,rhCygb）单克隆抗体,并建立检测该蛋白双抗体夹心ELISA法,为下一步研究rhCygb药代动力学做准备。方法用纯化的rhCygb免疫BALB/c小鼠,采用甲基纤维素半固体培养基法获得抗rhCygb的单克隆抗体杂交瘤细胞,间接ELISA法筛选制备单克隆抗体,建立双抗体夹心ELISA法。结果筛选获取了稳定分泌单克隆抗体的杂交瘤细胞株,通过抗原表位相加法实验获得5株表位不同的细胞株,Western-blotting验证能与rhCygb特异性结合,间接ELISA法验证其不与本实验室制备的其它PET28a-BL21蛋白及BL21裂解液发生交叉反应。本方法灵敏度为1.25ng/ml,在浓度为10～1250ng/ml时,线性关系良好,相关性达0.9931,实验内和实验间平均变异系数分别为6.2%和10.92%。结论成功建立了灵敏度好、特异性高的双抗体夹心法,为下一步研究rhCygb药代动力学奠定了基础。     

A high throughput electrochemiluminescent cell-binding assay for therapeutic anti-CD20 antibody selection

A cell-based ELISA using suspension WIL2 cells in 96-well format was previously developed for measuring relative binding affinities of humanized anti-CD20 variants. We further developed a new cell-binding assay that uses high binding capacity carbon electrode plates for rapid attachment of suspension WIL2 cells and electrochemiluminescence for detection. Compared to the cell-based ELISA, which requires centrifugation for the manual wash steps, significant improvement in assay throughput was achieved by using a microplate washer. The assay can be performed on both 96- and 384-well plates with a standard curve range of 2.74-2000 ng/ml, which is wider than the range of 15.6-1000 ng/ml for the cell-based ELISA. Using CD20 expressing CHO cell clones, surface expression of >or=33,000 CD20 molecules was sufficient to obtain a dose-response curve in 384-well format. Relative affinities of 15 humanized variants correlated well (r(2)=0.94) between electrochemiluminescent cell-binding assay and cell-based ELISA. A competitive assay format, using mouse anti-CD20 antibody as the tracer, with a dose-response range of 27.4-20,000 ng/ml was also developed. The new cell-binding assay method can be used to efficiently support humanization process for selection of anti-CD20 antibody drug candidates and to characterize antibody binding to other cell surface proteins.     

IL‐6, but not IL‐4, stimulates chemokinesis and TNF stimulates chemotaxis of tissue mast cells: involvement of both mitogen‐activated protein kinases and phosphatidylinositol 3‐kinase signalling pathways

Misiak‐T?oczek A, Brzezińska‐B?aszczyk E. IL‐6, but not IL‐4, stimulates chemokinesis and TNF stimulates chemotaxis of tissue mast cells: Involvement of both mitogen‐activated protein kinases and phosphatidylinositol 3‐kinase signalling pathways. APMIS 2009; 117: 558–67. An increase in the number of mast cells within tissues is observed in many pathophysiological conditions. Current data indicate that migration of mature mast cells might be one of the key mechanisms responsible for rapid local accumulation of these cells. Considering that interleukin (IL)‐6 and IL‐4, as well as tumour necrosis factor (TNF), influence mast cell activity in various ways, the purpose of the current study was to examine whether these cytokines function as rat peritoneal mast cell chemoattractants. We showed that IL‐4, in the concentration range from 10^?6 to 10^?3 ng/ml, did not induce a mast cell migratory response, even in the presence of laminin and fibronectin. Under the same experimental conditions, mast cells were shown to migrate in response to IL‐6 stimulation in the presence of laminin. The optimal concentration of IL‐6 for maximal migration of mast cells was 10^?4 ng/ml (i.e. ～5 nM). In comparison, the optimal concentration of TNF for maximal migration of mast cells was 5 × 10^?5 ng/ml (i.e. ～3 fM). IL‐6‐stimulated mast cell migration was the result of chemokinesis, whereas TNF‐induced migration was the result of chemotaxis. Mast cell migratory responses to IL‐6 and TNF were entirely blocked by specific anti‐IL‐6R and anti‐TNFR1 antibodies. We also documented that the migration response of mast cells to stimulation with IL‐6 and TNF was mediated through signal transduction pathways involving mitogen‐activated protein kinases and phosphatidylinositol 3‐kinase. Taken together, our results indicate that IL‐6, as well as TNF, induces tissue mast cell migration. Thus, these proinflammatory cytokines can be responsible for mast cell accumulation at the site of diverse conditions accompanied by inflammation.     

The establishment of a combined serum-free and serum-supplemented culture method of obtaining functional cord blood-derived human mast cells

BACKGROUND: Serum-free cultures supplemented with stem cell factor (SCF) and IL-6 is reported to support the extensive growth of less functional human cord blood-derived mast cells. OBJECTIVE: To obtain more functional mast cells from cord blood, we developed a culture system combining a serum-free condition for 0-8 weeks of culture, and followed by a serum-supplemented culture condition and examined the function of the cells compared to the cells cultured continuously in serum-free condition. METHODS: Human cord blood progenitors were purified with anti-CD133 antibody. They were cultured in a serum-free medium StemSpan supplemented with SCF at 100 ng/ml and IL-6 at 50 ng/ml for 8 weeks. Then, an aliquot of the cultured cells were cultured in the above condition but further supplemented with 10% fetal calf serum (FCS). RESULTS: The addition of FCS after 8 weeks of culture significantly increased the amount of histamine per mast cell (3.8 pg/cell) when compared to the serum-free condition (0.7 pg/cell). The cells cultured with FCS after 8 weeks expressed more FcvarepsilonRI alpha and released >30% of the histamine content upon anti-IgE stimulation than those cultured without serum. CONCLUSION: It is uncertain why FCS enhanced the functional maturation of mast cells when added after week 8 of culture but suppressed mast cell development when added at day 0 of culture. Yet, the present method combining a serum-free culture system with a serum-supplemented culture system seems to be beneficial for most of the laboratories to obtain functional human mast cells.     

Histamine release from dispersed human intestinal mast cells

To study the human intestinal mast cell of children and adults, we combined a sensitive glassfibre-based histamine assay with the enzymatic and mechanical dispersion of surgical specimens or mucosal biopsies. The method yields between 1.2 x 10(3) to 4.6 x 10(3) mast cells/mg tissue constituting 1.2% to 5.3% of total cell count. The mast cell yield, however, depends on the intestinal tissue specimen used for dispersion. Aliquots containing 1500 mast cells per sample are sufficient for measuring significant amounts of histamine (greater than or equal to 0.15 ng histamine per sample), thus making it possible, to carry out approximately 75 tests for four mucosal biopsies of 10 mg each. The intestinal mast cell releases histamine in a dose-dependent manner on challenge with anti-IgE (6-600 U/ml), ionophore A23187 (0.25-1.0 microM), and Concanavalin A (0.7-25.0 micrograms/ml). The histamine release shows interindividual variation with a net histamine release between 0 to 2.5 ng/samples dependent on the secretatogue. In general, it is not necessary to passively sensitize the mast cells to obtain a sufficient histamine release response to anti-IgE challenge, indicating the presence of intact and functional cell-bound IgE. However, it is shown that four of 10 non-atopic intestinal mast cell samples could be passively sensitized with human plasma containing either mite- or grass-specific IgE without stripping off the IgE first. This indicates the presence of free and preserved Fc-receptors on the dispersed mast cells in some subjects. In addition, it is found that the phorbolester TPA increases the histamine release response to A23187 and turns anti-IgE non-responding mast cells into responding mast cells, but TPA alone at 2 to 16 ng/ml has no histamine releasing effect. In patients with anti-IgE responding mast cells no additional effect of TPA is seen. Finally, no substantial differences between mast cells of children and adults are demonstrated.     

Development of a new,more sensitive immunoassay for human tryptase: Use in systemic anaphylaxis

Tryptase, a neutral protease, is selectively concentrated in the secretory granules of human mast cells, and its release into the circulation serves as a clinical marker of mast cell activation. The current study describes a new, more sensitive ELISA utilizing a newly developed, mouse monoclonal IgG1 antibody for capture called B12 and capable of detecting tryptase in normal plasma and serum. The greater sensitivity of the new immunoassay results in part from a greater portion of tryptase being detected. Mean levels of tryptase in serum from normal subjects from Richmond, Virginia (4.9 ng/ml;n=56), Munich, Germany (3.8 ng/ml;n=19), and Amersfoort, The Netherlands (1.9 ng/ml;n=8) were as indicated. In 62 subjects with ongoing allergic rhinitis, tryptase levels were no different in serum than for 19 normal controls, indicating that local mast cell activation is not necessarily reflected in the circulation. In 61 subjects sensitive to honey bee or yellow jacket venom by history, the 17 destined to have a severe, hypotensive response to a sting challenge had higher levels of tryptase at baseline than mild reactors, nonreactors, and controls, suggesting that baseline levels of tryptase may predict the severity of the clinical response to allergen in sensitive subjects.     

Evidence of ongoing mast cell and eosinophil degranulation in symptomatic asthma airway.

To assess whether mast cell and eosinophil (EOS) degranulation occurs in the airway of subjects with moderately symptomatic asthma, we have measured levels of preformed mast cell-derived mediators (histamine and tryptase) and EOS-derived mediators (major basic protein and EOS-derived neurotoxin) in bronchoalveolar lavage fluid (BALF) obtained from patients with symptomatic (N = 14) and asymptomatic asthma (N = 9) and patients without asthma (N = 6). Both the FEV1 (1.52 +/- 0.33 L:55% +/- 15% of predicted FEV1) and the forced expiratory flow at 50% (FEF50) (1.11 +/- 0.62 L/sec:26% +/- 14% of predicted FEF50) in the patients with symptomatic asthma were significantly lower than the corresponding values for FEV1 (3.16 +/- 0.45 L:86% +/- 10% of predicted FEV1) and the FEF50 (4.04 +/- 1.54 L/sec:71% +/- 25% of predicted FEF50) in the patients with asymptomatic asthma. Levels of histamine (4.8 +/- 5.0 ng/ml versus 0.2 +/- 0.2 ng/ml) (p = 0.05), EOS-derived neurotoxin (420.6 +/- 959.4 ng/ml versus 12.6 +/- 7.7 ng/ml) (p = 0.05), major basic protein (31.4 +/- 46.6 ng/ml versus less than 9 ng/ml) (p = 0.05), and percent EOSs (10.6% +/- 7.0% versus 1.1% +/- 0.9% of BAL cells) (p = 0.0006) were all significantly elevated in BALF from symptomatic compared to asymptomatic patients with asthma. The elevated levels of tryptase (13.2 +/- 14.8 ng/ml versus 3.9 +/- 3.9 ng/ml) in BALF from symptomatic compared to asymptomatic patients with asthma approximated, but did not reach, statistical significance. Spontaneous histamine release from BAL mast cells of symptomatic patients with asthma was 46% +/- 5% compared to 5% +/- 2% in asymptomatic patients with asthma. In response to antihuman IgE, histamine release from BAL mast cells recovered from asymptomatic patients with asthma increased to 25% +/- 10%, whereas in BAL mast cells of symptomatic patients with asthma, no anti-IgE potentiation of histamine release occurred. This study suggests that mast cell and EOS degranulation is ongoing in the airway of patients with moderately symptomatic asthma.     

Typical and atypical mast cells of the rat gastrointestinal system: Distribution and correlation with tissue histamine

Mast cells and histamine are present throughout the rat gastrointestinal system. Typical mast cells, differentiated from atypical mast cells by morphology, staining characteristics, and response to Compound 48/80, were the only mast cell type identified by histology in the cheek, tongue, esophagus, and nonglandular stomach. Atypical mast cells were found in large numbers in the glandular stomach, small and large intestine, and cecum, where they outnumbered typical mast cells by up to 201. Gastrointestinal histamine levels varied from 2.6 to 19.3 ng/mg in all tissues surveyed except for the glandular stomach, which contained 26 ng/mg. The amount of histamine per typical mast cell was estimated to be approximately 1.29 picograms; atypical mast cells contained less than 0.15 picograms per cell. Parenteral administration of Compound 48/80 resulted in the degranulation of typical mast cells, but not atypical mast cells, as determined by a fall both in typical mast cell number and a decrease in tissue histamine in areas rich in typical mast cells. These results indicate that striking regional differences in mast cell distribution and tissue histamine levels exist in the rat gastrointestinal system.     

IL-33 induces IL-13 production by mouse mast cells independently of IgE-FcepsilonRI signals

The IL-1-related molecules, IL-1 and IL-18, can promote Th2 cytokine production by IgE/antigen-FcepsilonRI-stimulated mouse mast cells. Another IL-1-related molecule, IL-33, was identified recently as a ligand for T1/ST2. Although mouse mast cells constitutively express ST2, the effects of IL-33 on mast cell function are poorly understood. We found that IL-33, but not IL-1beta or IL-18, induced IL-13 and IL-6 production by mouse bone marrow-derived, cultured mast cells (BMCMCs) independently of IgE. In BMCMCs incubated with the potently cytokinergic SPE-7 IgE without specific antigen, IL-33, IL-1beta, and IL-18 each promoted IL-13 and IL-6 production, but the effects of IL-33 were more potent than those of IL-1beta or IL-18. IL-33 promoted cytokine production via a MyD88-dependent but Toll/IL-1R domain-containing adaptor-inducing IFN-beta-independent pathway. By contrast, IL-33 neither induced nor enhanced mast cell degranulation. At 200 ng/ml, IL-33 prolonged mast cell survival in the absence of IgE and impaired survival in the presence of SPE-7 IgE, whereas at 100 ng/ml, IL-33 had no effect on mast cell survival in the absence of IgE and reduced mast cell survival in the presence of IgE. These observations suggest potential roles for IL-33 in mast cell- and Th2 cytokine-associated immune responses and disorders.     

ELISA measurement of IgG subclass production in culture supernatants using monoclonal antibodies

Specific and sensitive ELISA to quantitate the human IgG subclasses in cell culture supernatants are described. These assays detect a minimum of 5 ng/ml IgG1, 90 ng/ml IgG2, 8 ng/ml IgG3 and 8 ng/ml IgG4 and can generally measure IgG subclasses in lymphocyte cultures containing a minimum of 200 ng/ml of total IgG. The isotype specificity of these ELISA is demonstrated and each individual ELISA shown to react with a number of paraproteins of the relevant subclass independently of their light chain type or their (major Caucasian) allotype. These assays have been used to determine the IgG subclass response of normal human lymphocytes to pokeweed mitogen in vitro.     

芝麻素通过PKCα/ NF-κB 信号途径抑制肥大细胞活化

目的:观察芝麻素对肥大细胞活化和炎症介质释放的影响并探讨其可能的作用机制。方法:体外培养HMC-1细胞,用10 μg/ ml 的anti-DNP IgE 处理细胞6 h 后,再用100 ng/ ml 的DNP-HAS 孵育10 min 诱导HMC-1 细胞活化,在DNP-HAS 处理前给予最终浓度25、50 和100 μg/ L 芝麻素预处理30 min 后光镜下观察芝麻素对肥大细胞脱颗粒的影响,ELISA 法检测芝麻素对肥大细胞组胺、TNF-α、IL-6、IL-1β、IL-8 释放的影响,Western blot 方法观察芝麻素对Fc RI 受体下游信号Lyn 和 Syk,PKC琢激活,IκB琢磷酸化和NF-κB 活化的影响。结果:DNP-HAS 能明显诱导HMC-1 细胞脱颗粒,促进组胺和TNF-α、IL-6、IL-1β和IL-8 等细胞因子的释放,激活Fc着RI 受体下游信号分子Lyn、Syk 和PKCα,磷酸化IκBα,促进NF-κB 活化(P<0.05)。芝麻素高(100 μg/ L)、中(50 μg/ L)浓度能明显抑制HMC-1 细胞脱颗粒和炎症介质的释放,阻断Fc着RI 受体下游信号激活,抑制NF-κB 活化(P<0.05)。结论:芝麻素通过PKCα/ NF-κB 途径抑制肥大细胞活化和炎症介质释放。