基因芯片检测吴茱萸碱对小鼠DC细胞功能调控相关基因表达的影响

目的：利用基因芯片技术检测吴茱萸碱对小鼠骨髓来源DC功能调控相关基因表达的影响。方法：分离BALB／c小鼠骨髓细胞，经GM-CSF体外诱导培养10天的未成熟DC细胞（iDC）经不同因素处理并分为：对照组（Ⅰ）、吴茱萸碱组（EVO）（Ⅱ）、内毒素（LPS）组（Ⅲ）、EVO＋LPS组（Ⅳ），24小时后收集各组细胞，抽提总RNA，利用SuperArray公司小鼠DC与抗原提呈细胞基因芯片MM-604对细胞功能相关基因进行检测。结果：Ⅱ／Ⅰ上调≥2倍基因7个，下调≥2倍基因10个；Ⅲ／Ⅰ上调≥2倍基因37个，下调≥2倍基因12个；Ⅳ／Ⅱ上调≥2倍基因46个，下调≥2倍基因7个；Ⅳ／Ⅲ上调≥2倍基因24个，下调≥2基因2个，对这些基因功能进行检索分类，主要涉及细胞因子分泌及其受体表达、抗原摄取、抗原提呈、细胞表面受体、信号传导。结论：吴茱萸碱对DC作用涉及多个基因的表达调控，这些基因控制并影响着DC功能、分化和成熟，为进一步寻找药物靶点提供了线索。     

4种细胞因子组合方式对小鼠树突状细胞分化发育的影响

目的观察在体外培养时4种细胞因子(CK)组合方式对小鼠骨髓源树突状细胞(DC)分化、增殖、发育的影响.方法用不同的CK定向诱导小鼠骨髓细胞分化为DC,通过流式细胞仪(荧光抗体双标记法)测定CD11c+细胞比例、MHC-Ⅱ类分子的表达及在脂多糖(LPS)刺激后CD86表达的变化.结果GM-CSF+IL-3+SCF促进DC分化、增殖的能力明显高于其他3组(P＜0.05).该组CK所诱导的DC在LPS刺激后,CD86表达增加的幅度明显低于GM-CSF+IL-4组(P＜0.01).结论GM-CSF、IL-3和SCF对于促进小鼠骨髓细胞向DC定向分化、增殖有协同作用,分化后的DC多数处于发育早期,DC前体所占的比例较大.     

Jagged-1对骨髓来源树突状细胞生成细胞因子的影响

目的:探讨可溶性Jagged-1/Fe嵌合蛋白(Jagged-1)对重组小鼠粒细胞-巨噬细胞集落刺激因子(rmGM-CSF)和白细胞介素4(rmIL-4)体外诱导小鼠骨髓来源树突状细胞(DC)产生细胞凶子的影响.方法:建立rmCM-CSF和rmIL-4体外诱导DC的模型,观察Jagged-1/Fc对DC分化的形态学影响.通过Luminex蛋白液相芯片技术和ELlSA检测其细胞因子的表达水平,藉MTT法测定可溶性Jagged-1/Fc诱导的DC对同种异基因淋巴细胞增殖的刺激能力.结果:除了TGF-β,Jag-ged-1/Fc诱导的DC与细菌脂多糖(LPS)或酵母聚糖A诱导的DC不同,表现为生成TNF-α的水平明显降低,IL-4显著增高,而IL-10、IL-6、IL-2、IL-12和IFN-γ的水平与对照组无明显差异.γ分泌酶抑制剂DAFT能逆转Jagged-1/Fc抑制DC生成TNF-α.混合淋巴细胞反应显示Jagged-1/Fc诱导的DC对T细胞增殖的刺激能力最弱,LPS诱导的DC的刺激能力最强.结论:Jagged-1/Fc诱导的DC倾向介导免疫耐受,指导初始T细胞向Th2细胞偏离.     

盐酸小檗碱对小鼠脾细胞增殖和凋亡及分泌细胞因子的影响

目的 研究盐酸小檗碱(BBR)对小鼠脾细胞增殖与凋亡及细胞因子产生的影响.方法 采用无菌取BALB/c小鼠脾脏,制成脾细胞悬液,脾细胞预先用(1、2、4) μg/mL BBR处理60 min,加入刀豆蛋白(ConA)刺激脾细胞增殖,细胞培养至24、48、72 h时,用MTT方法检测脾细胞增殖情况;流式细胞术检测脾细胞培养不同时间的凋亡情况,用细胞因子ELISA检测试剂盒定量分析细胞上清液中TNF-α,IL-2和IFN-γ的浓度.结果 与对照组相比,在以上浓度范围内,BBR对ConA刺激下实验组小鼠脾细胞的增殖和TNF-α,IL-2,IFN-γ产生有明显的抑制作用(P＜0.05),且呈浓度及时间依赖性,但对小鼠脾细胞凋亡无明显影响(P>0.05).结论 BBR对小鼠脾细胞具有明显的免疫抑制作用,可作为潜在的免疫抑制药物.     

小檗碱对小鼠DTH及其体内几种细胞因子的影响

目的 :以二硝基氟苯 (DNFB)所致迟发型超敏反应 (DTH)小鼠模型观察小檗碱对小鼠DTH及其体内几种重要细胞因子的影响。方法 :采用 1%DNFB腹部致敏、耳廓发敏的方法建立DTH小鼠模型 ,以巨噬细胞NO2 -释放法测定血清IFN γ水平 ,胸腺细胞法检测IL 1水平 ,丝裂原激活的淋巴母细胞法检测IL 2水平 ,L92 9细胞结晶紫染色法测定TNF α水平。结果 :发现小檗碱可抑制DNFB诱导的小鼠DTH ,降低其血清IFN γ水平 ,抑制其腹腔MΦ产生IL 1及TNF α ,抑制其脾细胞产生IL 2。结论 :表明小檗碱有抑制小鼠DTH的作用 ,其机制可能是抑制了IFN γ、IL 1、TNF α、IL 2等细胞因子的产生和分泌 ,从而抑制免疫反应 ,减轻炎症损伤。     

小鼠胸腺树突状细胞系的克隆化及基本鉴定

目的：应用单细胞培养系统,对本室建成的胸腺基质细胞系ＭＴＳＣ４进行细胞克隆化并鉴定。方法：在单个细胞培养中,扩增出一个细胞长成的克隆,并使之稳定生长后,进行表面标志分子和倍增时间检查,并以其分泌的细胞因子测定其生物不特性及功能。结果;获得１４个细胞克隆,它们均表达树突状细胞抗原和ＭＨＣ－Ⅱ类分子,均无角蛋白,表明各克隆均为树突状细胞,起始的ＭＴＳＣ４也是树突状细胞系。     

催乳素对小鼠脾脏CD11c+树突状细胞合成细胞因子的调控

本研究采用逆转录-多聚酶链反应(RT-PCR)方法,在mRNA水平上了解不同浓度的催乳素(PRL)对小鼠脾脏树突状细胞CD11c+(spleen CD11c-positive dendritic cells,SDC)合成细胞因子的影响。结果表明,低(0.01 nmol/L)、中浓度(0.1nmol/L)的PRL可以上调IL-6、IL-10、IL-12和TNF-α的水平而高浓度(1 nmol/L)则降低它们的表达(IL-12除外)。这提示PRL可能通过改变抗原提呈细胞SDC细胞因子的合成,进而参与调节机体的生理或病理性免疫反应。     

青藤碱促进树突状细胞分化抑制其成熟

目的 探讨青藤碱对树突状细胞(Dendritic cell,DC)体外分化发育、成熟、抗原递呈及刺激T细胞活化能力的影响.方法 DC体外培养时,青藤碱处理,观察细胞生长情况,流式检测细胞表型及抗原内吞能力,混合淋巴细胞反应检测DC刺激T细胞活化的能力,E(I)ISA检测细胞因子分泌.结果 与对照组相比,青藤碱处理DCCD1a表达上调而CD14下调,IL-12分泌减少,共刺激分子表达减少,同种T细胞刺激活性降低.结论 合适剂量的青藤碱能刺激单核细胞分化为不成熟DC但能抑制其进一步成熟.     

吴茱萸碱抑制荷瘤小鼠结肠癌HCT-116细胞增殖

目的研究吴茱萸碱(Evo)对人结肠癌荷瘤Balb/c裸鼠HCT-116细胞增殖的影响,并探讨其可能机制。方法用HCT-116细胞接种到4周龄的Balb/c裸小鼠右下腋部,待荷瘤直径约0.5 cm后用灌胃针灌入Evo(3 mg/kg)进行治疗,每3 d测瘤体直径及小鼠质量,绘制质量曲线及瘤体体积曲线,灌喂22 d后处死,取瘤体组织;HE染色法验证Balb/c裸鼠瘤体的成瘤情况;免疫组化检测瘤体HDAC3、NF-κB、p53的表达;Westernblot检测瘤体组蛋白去乙酰化酶HDAC3、NF-κB、p53的变化。结果 Evo灌喂组小鼠的瘤体体积和瘤体质量明显小于对照组,质量较对照组重;Evo灌喂组肿瘤细胞皱缩,胞核深染,较对照组核分裂像明显减少;经吴茱萸碱处理的裸鼠的瘤体中NF-κB、p53表达量较对照组增高,HDAC3则反之(P0.05)。结论吴茱萸碱可以通过下调HDAC3来影响NF-κB及p53蛋白的表达,抑制人结肠细胞系HCT-116的体内增殖。     

Effects of cytokine milieu secreted by BCG-treated dendritic cells on allergen-specific Th immune response

Bacillus Calmette-Guerin (BCG) is reported to suppress Th2 response and asthmatic reaction. Dendritic cells (DCs), the major antigen-presenting cells, infections with BCG are known to result in inducing various cytokines. Thus, DCs are likely to play a role in the effects of BCG on asthma. This study aims at investigating that cytokine milieu secreted by BCG-treated DCs directly enhances allergen-specific Th1 response and/or suppresses Th2 response in allergic asthma. DCs and CD3+ T cells were generated from Dermatophagoides farinae-sensitive asthmatics. DCs were cultured with and without BCG and subjected to flow cytometric analysis. IL-12 and IL-10 were determined from the culture supernatants. Some DCs were cocultured with T cells in the presence of D. farinae extracts after adding the culture supernatants from BCG-treated DCs, and IL-5 and IFN-gamma were determined. BCG-treated DCs enhanced significantly the expressions of CD80, CD86, and CD40, and the productions of IL-12 and IL-10. Addition of culture supernatants from BCG-treated DCs up-regulated production of IFN-gamma by T cells stimulated by DCs and D. farinae extracts (p<0.05), but did not down-regulate production of IL-5 (p>0.05). The cytokine milieu secreted by BCG-treated DCs directly enhanced allergen-specific Th1 response, although did not suppress Th2 response.     

Differing effects of clarithromycin and azithromycin on cytokine production by murine dendritic cells

Summary The macrolide antibiotics are now well known to have anti-inflammatory effects. Because dendritic cells (DCs) orchestrate immune responses, we examined the in vitro effects of clarithromycin (CAM), azithromycin (AZM) and midecamycin (MDM) on the expression of co-stimulatory molecules and production of cytokines [interleukin (IL)-10, IL-6, interferon (IFN)-gamma, IL-12p40, tumour necrosis factor (TNF)-alpha] of murine bone marrow-derived DCs by lipopolysaccharide (LPS) stimulation. A 15-membered macrolide, AZM, and a 14-membered macrolide, CAM, significantly enhanced the intensity of a co-stimulatory molecule, CD80, on DCs but not CD86 and CD40. AZM significantly increased the production of IL-10 and CAM significantly inhibited the production of IL-6 by DCs. However, a 16-membered macrolide, MDM, did not have any significant effect on these surface markers and cytokine productions. Moreover, AZM increased IL-10 and CAM decreased IL-2 productions significantly, when naive T cells derived from spleen were co-cultured with DCs treated in advance with LPS and these macrolides. These findings suggest that 14-membered and 15-membered, but not 16-membered macrolides play as anti-inflammatory agents, at least in part, through modulating the functions of DCs. However, each macrolide affects them in different ways.     

MCF-7 乳腺癌细胞培养上清对树突状细胞抑制作用的研究

目的:应用MCF-7乳腺癌细胞分泌的上清液培养正常外周血树突状细胞,探讨MCF-7乳腺癌细胞分泌因子对正常树突状细胞分化、成熟及功能的影响.方法:应用MCF-7 乳腺癌细胞的培养上清和GM-CSF、IL-4及TNF-α培养正常外周血单个核细胞,检测所诱导的树突状细胞(DC)及其致敏的CTL活性.结果:MCF-7 乳腺癌细胞培养上清能够明显抑制正常树突状细胞的分化成熟及抗原提呈能力,CD80、CD83、CD86和HLA-DR的表达明显降低,与正常对照差异显著(P＜0.01);CTL对MCF-7细胞杀伤活性为17.35%与对照组56.14%比较差异显著(P＜0.01);IL-12分泌和共刺激T淋巴细胞所分泌的IFN-γ明显降低(P＜0.01).结论:MCF-7 乳腺癌细胞上清明显抑制所共培养的树突状细胞的分化、成熟及抗原提呈能力.     

Effects of murine leukemia viruses on the function of dendritic cells

In asymptomatic human immunodeficiency virus-1 infection T cells respond normally to allogeneic dendritic cells (DC), but DC show reduced stimulatory capacity. By contrast in HTLV-1 infection no significant changes in allogeneic stimulation were seen but DC-stimulated activity of autologous T cells. In seeking animal models relevant to these diseases the effects of two murine leukemia retroviruses, Rauscher leukemia virus (RLV) and Moloney leukemia virus (MLV) on the function of dendritic cells and T cells in a primary mixed leucocyte reaction have been tested. Treatment by RLV in vitro suppressed the ability of DC to stimulate allogeneic T cells from healthy animals. MLV at the same concentration did not significantly affect the ability of DC to stimulate allogeneic T cells, but provoked considerable enhancement of the low level stimulation by DC in the syngeneic system. Similar results were obtained following in vivo exposure to viruses. Two pieces of evidence suggested that these effects were due to impairment of DC function and were not operating through infection of T cells. Firstly, exposure of T cells directly to virus in vitro and in vivo before stimulation with untreated allogeneic DC caused no significant alteration in T cell activity. Secondly, the impact of murine leukemia virus on DC function was not abrogated when infected DC were added to normal T cells and cultured in the presence of zidovudine. Treatment of DC by RLV caused a decrease of cluster formation with allogeneic T cells. No statistically significant influence of MLV was observed on cluster formation after 3-h of incubation in the allogeneic system. However, after 18-h incubation MLV-treated DC formed fewer clusters with T cells than untreated DC. At the same time a stimulatory effect of MLV on DC cluster formation with syngeneic T cells was found. Considerable decrease was found in major histocompatibility complex class II antigen and LFA-1 receptor expression on the DC surface in mice infected by RLV MLV induced no significant changes. These mouse retroviruses can therefore cause changes in DC function similar to those already reported using human retroviruses and may provide models for studying their effects.     

小鼠骨髓瘤细胞分泌的免疫球蛋白对其自身增殖作用的体外研究

为了研究小鼠骨髓瘤细胞系P3X63Ag8所分泌的免疫球蛋白(immunoglobulin,Ig)对其自身增殖的影响,首先用ELISA方法检测P3X63Ag8细胞培养上清中的Ig含量;而后以不同浓度的P3X63Ag8细胞培养上清作用于P3X63Ag8细胞,通过3H-TdR掺入和MTT比色法检测细胞增殖水平,并比较P3X63Ag8细胞与其他肿瘤细胞对该培养上清的反应性;最后以抗小鼠IgG抗体中和P3X63Ag8细胞分泌的Ig,观察其对细胞增殖的影响。结果显示,P3X63Ag8细胞分泌小鼠IgG;不同浓度的P3X63Ag8细胞培养上清均可促进细胞增殖,并具有一定的剂量依赖性;与P3X63Ag8细胞不同,小鼠乳腺癌细胞系4T1的增殖不受P3X63Ag8细胞培养上清的影响;以抗小鼠IgG抗体中和P3X63Ag8细胞分泌的Ig,可部分抑制P3X63Ag8细胞增殖。该结果表明,小鼠骨髓瘤细胞分泌的Ig可能具有促进骨髓瘤细胞增殖的能力,这为我们更加深入理解多发性骨髓瘤的发病机制提供了一定的实验依据。     

Autophagy regulates long-term cross-presentation by murine dendritic cells

Autophagy has been reported to be involved in supporting antigen cross-presentation by dendritic cells (DCs). We have shown that DCs have the ability to store antigen for a prolonged time in endolysosomal compartments and thereby sustain MHCI antigen cross-presentation to CD8⁺ T cells. In the current study, we investigated the role of autophagy in long-term antigen presentation. We show that the autophagy machinery has a negative impact on storage of antigen in DCs. Atg5^–/–DCs which are deficient in autophagy or DCs treated with common autophagy inhibitors showed enhanced antigen storage and antigen cross-presentation. This augmented antigen cross-presentation effect is independent of altered proteasome enzyme activity or MHCI surface expression on DCs. We visualized that the storage compartments are in close proximity to LC3 positive autophagosomes. Our results indicate that autophagosomes disrupt antigen storage in DCs and thereby regulate long-term MHCI cross-presentation.