携带幽门螺杆菌ureB和IL-2质粒DNA的减毒鼠伤寒沙门菌疫苗构建

目的　构建编码幽门螺杆菌 (Helicobacterpylori,H .pylori)尿素酶B亚单位 (ureB)基因和小鼠IL 2基因以减毒鼠伤寒沙门菌为载体的核酸疫苗 ,体外转染Cos 7细胞 ,鉴定其表达蛋白的免疫性。方法　应用聚合酶链式反应 (PCR)技术从H .pylori标准菌株CCUG1 7874基因组DNA扩增ureB基因 ,从重组质粒 pCIneo IL 2扩增小鼠IL 2基因 ,通过T A克隆分别插入 pUCmT载体 ,检测ureB及IL 2的核苷酸序列 ,通过酶切、连接反应分别克隆入真核表达载体 pIRES ,PCR和酶切反应进行鉴定 ;重组载体 pIRES ureB和 pIRES ureB IL 2转入减毒鼠伤寒沙门菌LB50 0 0 ,抽提质粒 ,再次转入SL72 0 7,反复传代 ,鉴定核酸疫苗载体菌的稳定性。通过脂质体法将重组载体 pIRES ureB和pIRES ureB IL 2转染Cos 7细胞 ,SDS PAGE及Westernblot法检测表达蛋白的免疫性。结果　扩增出长约 1 70 0bp的ureB基因和 51 0bpIL 2 ,测序结果表明 ,扩增出的ureB基因与基因库H .pyloriureB序列一致 ,IL 2序列和小鼠的IL 2序列一致 ,PCR和酶切鉴定结果证实ureB和IL 2基因克隆入真核表达载体 pIRES ,并成功构建了稳定的幽门螺杆菌ureB和IL 2基因以减毒鼠伤寒沙门菌为载体的核酸疫苗 ,并且以Westernblot检测到特异性的相对分子质量 (Mr)为 6 6× 1 0 3的UreB蛋白     

人类基因XAPC7真核表达载体的构建及其在SMMC-7721细胞中的表达

目的:构建pcDNA3.1(-)/XAPC7真核表达载体并检测其在人肝癌细胞系SMMC-7721中的表达.方法:采用PCR法从pET28b/XAPC7重组质粒中克隆得到XAPC7 cDNA全长序列,将之与pMD18-T载体连接、测序后将该片段亚克隆到真核表达载体pcDNA3.1(-)中.构建好的pcDNA3.1(-)/XAPC7真核表达质粒经酶切鉴定后,采用脂质体法将该重组质粒转染人肝癌细胞系SMMC-7721,经G418筛选,得到阳性克隆细胞株,再应用半定量RT-PCR技术检测转染前后该细胞株XAPC7基因的mRNA表达水平.结果:pcDNA3.1(-)/XAPC7经酶切鉴定及DNA测序证实,目的基因XAPC7的序列完全正确,真核表达载体构建成功;经RT-PCR检测,重组质粒转染株的XAPC7基因mRNA表达水平高于对照组,证实XAPC7基因已经稳定转染到SMMC-7721细胞中并得到表达.结论:成功地建立了人基因XAPC7的稳定转染细胞株,为进一步研究XAPC7的功能奠定了实验基础.     

重组人sCR1真核表达载体的构建、表达及其生物学活性

目的:采用酵母细胞分泌型载体pPIC9k表达人可溶性补体受体(sCR1),研究重组人sCR1融合蛋白的体外生物学活性.方法:从人外周血中提取总RNA,应用RT-PCR获得人sCR1全长cDNA,然后将其克隆入毕赤酵母细胞分泌型表达载体pPICgk中,构建含人sCR1的重组质粒(pPIC9ksCR1),经测序鉴定正确,电转化入毕赤酵母细胞SMD1168中,将经G418抗性筛选出的重组sCR1酵母细胞株进行PCR鉴定,经甲醇诱导,表达产物经SDS-PAGE分析和Westernblot鉴定,通过Ni2 -NTA agarose亲和层析纯化后进行生物学活性鉴定.结果:获得毕赤酵母细胞分泌型表达载体pPIC9k-sCRI,经G418筛选及PCR鉴定得到高拷贝整合的重组酵母细胞株,经甲醇诱导含pPIC9k-sCR1的酵母SMD1168细胞表达出重组sCR1融合蛋白.此蛋白在SDS-PAGE上表现为Mr,约31 1300的蛋白区带,在Western blot分析中可被sCR1的CD35单克隆抗体(mAb)识别.经Ni2 -NTA agarose亲和层析纯化后得到较纯的sCR1融合蛋白及较高的生物学活性.结论:人sCR1融合蛋白在酵母细胞表达系统中的高水平表达,并且有与人体天然蛋白相同的抗原性及其生物学活性.     

独特型TCR Vα1-pIRES-TCR Vβ8表达载体构建及体外表达

目的:构建Jurkat细胞株独特型TCR Vα1-pIRES-TCR Vβ8表达载体,转染后了解其体外表达情况.方法:根据聚合酶链反应-基因扫描(PCR-Genescan)检测Jurkat细胞株TCR Vα及Vβ亚家族表达情况,分别将其所表达的单克隆性的TCR Vα1及TCR Vβ8亚家族基因片段克隆至质粒pIRES的多克隆位点A(MCS A)和多克隆位点B(MCS B)中.通过限制性酶切分析、序列分析、RT-PCR、间接免疫荧光、流式细胞术(FCM)手段鉴定重组表达载体的正确性以及转染A549和Molt4细胞后基因及蛋白的表达情况.结果:构建了2组TCR Vα1-pIRES-TCR Vβ8表达载体,该表达载体转染A549和Molt4细胞后,在mRNA和蛋白水平检测到了TCR Vα1和TCR Vβ8的表达.结论:成功构建了2种独特型Vα1-pIRES-TCR Vβ8真核表达载体,为利用特异性TCR基因修饰T细胞的研究提供方法学依据.     

hTSHR胞膜外区片段真核表达载体的构建和表达

目的:构建人类促甲状腺激素受体(hTSHR)胞膜外区氨基端的两个片段hTSHRf(aa29 ～100)、 hTSHRe(aa101～278)的真核表达载体pcDNA3.1-hTSHRf和pcDNA3.1-hTSHRe, 并在CHO细胞中进行表达.方法:RT-PCR法从人甲状腺正常组织的cDNA中扩增hTSHRf和hTSHRe,定向插入真核表达载体pcDNA3.1(D)/V5-His-TOPO中, 经酶切、 PCR和测序鉴定后通过脂质体介导转染至CHO细胞中进行表达, RT-PCR扩增转染细胞的cDNA、 Western blot分别鉴定hTSHR在CHO细胞中mRNA和蛋白水平的表达.结果:RT-PCR分别扩增两个片段的阳性克隆株, 所得片段大小与预期一致, 经Western blot鉴定, 相对分子质量(Mr)分别为11900、 23600左右, 与预期的大小相符.结论:真核表达载体pcDNA3.1-hTSHRf和pcDNA3.1-hTSHRe构建成功, RT-PCR和Western blot检测证实重组质粒能在CHO细胞中高效表达, 为进一步研究pcDNA3.1-hTSHRf和pcDNA3.1-hTSHRe在体内的基因表达, 建立Graves'病的动物模型奠定了基础.     

CaMK Ⅱα基因启动子的克隆和神经细胞特异性Cre表达载体的构建

目的克隆和鉴定CaMKⅡα基因启动子序列，构建神经细胞特异性Cre重组酶的真核表达载体。方法采用高保真PCR方法分步扩增CaMKⅡα基因5′端8．1kb的调控区DNA片段，该片段包括了CaMKⅡα基因5′端调控区的所有序列。经克隆和部分序列测定后，依次与pCre—IRES—EGFP质粒框架连接，构建载体。结果克隆的CaMKⅡα基因5′端侧翼区酶切图谱与公布的C57BL/6J小鼠相应序列的酶切位点相一致，其中文献报道的富含顺式调控元件的序列与公布的小鼠序列完全相同。CaMKⅡα基因启动子正确地连接于Cre基因的5′端，构建了目标载体。结论这一载体的构建为建立前脑神经细胞特异性表达Cre重组酶的转基因小鼠奠定了基础，有助于神经系统相关疾病的研究。     

改造稀有密码子对rhFGF8a原核表达的影响

目的:构建重组人成纤维细胞生长因子8a(rhFGF8a)高效表达载体,提高该蛋白的表达量.方法:采用PCR技术设计引物替换rhFGF8a基因N端的稀有密码子以及稀有终止子,构建原核表达载体pET22b-mrhFGF8a,转化大肠杆菌,用异丙基β硫代半乳糖(IPTG)诱导表达,Sephacryl S-200纯化表达蛋白,MIT法检测其生物学活性.结果:表达产物经SDS-PAGE、Western blot鉴定,目的蛋白量占全菌蛋白的31%,Sephacryl S-200纯化后蛋白纯度可达97.28%,且具促进NIH3T3细胞增殖活性.结论:通过改造稀有密码子的方法有效地提高了真核基因在原核表达体系中的表达量.     

用单克隆抗体测定血中卵巢肿瘤抗原NB/70K(文摘)

作者用4种不同抗卵巢肿瘤抗原NB/7oK的单克隆抗体(NBi2123。、NB129i3、NBi3s34和NB13831),用放射免疫测定法(RIA)检测人血中卵巢肿瘤抗原NB/70K的水平。以区别健康人、良性妇科疾病与恶性卵巢疾病。 方法未治疗的卵巢癌患者60例,健康对照组99例、良(32例)、恶性(44例)乳腺、肺(良性30例,恶性51例)和胃肠(良性29例,恶性49例)疾病患者的血清冷藏一70℃备用,恶性病经临床和病理检查所证实。标本加入单克隆抗体(McAb)37℃孵育15 min,然后加入I‘23标记的NB/70K,在37℃中继续孵育40 min。冷却后加入沉淀剂与兔抗鼠球蛋白,37℃孵育40 m…     

人MASP1 N端片段原核表达载体的构建及其表达

目的:在大肠杆菌中表达人甘露聚糖结合凝集素(MBL)相关丝氨酸蛋白酶1(MASP1)N端片段.方法:采用PCR技术从含人MASP1 cDNA的质粒pGEM-MASP1中扩增MASP1-N端基因片段,将其插入原核表达载体pGEX4T-1,转化BL21(DE3)感受态菌诱导表达MASP1-N端蛋白,通过GSTrap亲合层析柱纯化目的蛋白,以SDS-PAGE和Westernblot进行鉴定,并以ELISA分析了目的蛋白与重组MBL-CLR、重组MBL的结合活性.结果:从pGEM-MASP1中扩增得到约860 bp的基因片段,构建成重组载体经酶切出现约4 900 bp和860 bp片段,测序结果与预期的完全一致.纯化蛋白经SDS-PAGE可见Mr60000蛋白带,该蛋白可与抗GST抗体反应并能与重组人MBL-CLR、重组人MBL蛋白结合.结论:获得了表达人MASP1 N端片段的大肠杆菌菌株和重组人MASP1 N端片段/GST融合蛋白,为MASP1分子的进一步研究提供了条件.     

超声联合神经刺激仪引导腰骶丛神经阻滞在 老年髋部手术中的应用

目的 探讨超声联合神经刺激仪引导腰骶丛神经阻滞在老年髋部手术中的应用效果。方法 选择2017年5月~2018年9月于我院接受髋部手术的老年患者76例,采用随机数字表法分为研究组与对照组,每组38例。两组患者均行腰骶丛神经阻滞,研究组采用超声联合神经刺激仪引导,对照组仅采用神经刺激仪定位,比较两组的阻滞完成时间、麻醉起效时间、下床活动时间、出院时间、麻醉维持时间和术后VAS疼痛评分。结果 研究组阻滞完成时间、麻醉起效时间、下床活动时间、出院时间分别为（12.08±2.14）min、（7.75±1.02）min、（4.27±1.09）d、（5.82±2.10）d,分别短于对照组的（17.85±3.94）min、（10.21±1.19）min、（6.05±1.47）d、（7.33±1.65）d,研究组麻醉维持时间为（781.78±30.14）min,长于对照组的（713.99±25.96）min,差异具有统计学意义（P＜0.05）。研究组患者术后2、4、8、24 h的VAS评分分别为（0.78±0.19）分、（0.85±0.24）分、（1.39±0.43）分、（1.66±0.65）分,分别低于对照组的（1.94±0.35）分、（3.27±0.71）分、（3.10±0.64）分、（3.07±0.78）分,差异具有统计学意义（P＜0.05）。结论 超声联合神经刺激仪引导腰骶丛神经阻滞在老年髋部手术中的应用准确度高,神经阻滞起效时间短,术后镇痛效果佳。     

结核分枝杆菌Esx-1 底物蛋白Rv3615c 的原核表达及其免疫功能研究

目的:构建结核分枝杆菌(M.tb)Esx-1 底物蛋白Rv3615c 的原核表达质粒pET30b-Rv3615c 并在大肠杆菌BL21(DE3)中进行原核表达;以全血IFN-β分析试验(WBIA)检测rRv3615c 蛋白能否被淮南市M.tb 感染者T 细胞所识别;在小鼠模型中检测其免疫原性。方法:以分子克隆技术构建重组载体pET30b-Rv3615c 并表达、纯化rRv3615c 蛋白,以WBIA 检测rRv3615c 抗原刺激淮南市M.tb 感染者和未感染者外周血淋巴细胞产生的特异性IFN-β水平。此外联合佐剂SAS 免疫C57BL/6 小鼠,评价其体液免疫应答和Th1 型应答水平。结果:成功构建pET30b-Rv3615c 质粒,SDS-PAGE 和Western blot 显示其正确表达和纯化。rRv3615c 蛋白特异性刺激淮南市M.tb 感染者淋巴细胞产生的IFN-β浓度显著高于健康对照者。Rv3615c/ SAS 诱导小鼠产生的IgG、IgG1、IgG2a 以及Rv3615c1SAS 诱导小鼠脾淋巴细胞分泌的特异性IFN-β、TNF-β和IL-2,均显著高于PBS 组和SAS 组,显示rRv3615c 可诱导趋向于Th1 型免疫应答。结论:Rv3615c 可被淮南市M.tb 感染者T 细胞识别,具有较强的免疫原性,是用于结核病(TB)预防和诊断的潜力靶抗原。     

The DosR antigen Rv1737c from Mycobacterium tuberculosis confers inflammation regulation in tuberculosis infection

There is an urgent need to identify the potential risk factors for activating latent Mycobacterium tuberculosis infection. In this study, we evaluated the immune function of Rv1737c, which is a latency‐associated antigen of dormancy survival regulator (DosR) of M. tuberculosis in a mouse model. Our data showed that mice pretreated with recombinant Rv1737c (rRv1737c) exhibited higher levels of antigen‐specific antibodies (IgG, IgM and IgA) than sham‐treated mice. Following Bacilli Calmette‐Guerin (BCG) challenge, rRv1737c adjuvanted with cholera toxin subunit B (CTB) induced diffuse lung inflammation and fibrosis compared to the control mice. The inflammatory pathogenesis due to rRv1737c pre‐exposure was associated with a switch in the macrophage phenotype from M1 to activated M2 and was characterized by IL‐10 production. Intracellular cytokine analysis further showed that the rRv1737c‐pretreated mice exhibited an increased frequency of Th2 cells in the lungs, lymph nodes and spleen after BCG challenge. Furthermore, IFN‐γ expression increased in the lungs after rRv1737c pretreatment compared to that in the sham mice. Accordingly, lung cells from rRv1737c‐immunized mice stimulated with killed BCG produced higher levels of multiple cytokines, such as IFN‐γ, IL‐10 and IL‐6. The results confirmed that the pathological features of rRv1737c promoted inflammation. Overall, our findings provide direct evidence of the pro‐inflammatory function of rRv1737c in a murine model of BCG infection, indicating that Rv1737c is a pathogenic antigen of M. tuberculosis and may be key to the recurrence of latent infection.     

CBA/J mice generate protective immunity to soluble Ag85 but fail to respond efficiently to Ag85 during natural Mycobacterium tuberculosis infection

In CBA/J mice, susceptibility to Mycobacterium tuberculosis (M.tb) is associated with low interferon-gamma (IFN-γ) responses to antigens (Antigen 85 (Ag85) and early secreted antigenic target-6 (ESAT-6)) that have been defined as immunodominant. Here, we asked whether the failure of CBA/J mice to recognize Ag85 is a consequence of M.tb infection or whether CBA/J mice have a general defect in generating specific T-cell responses to this protein antigen. We compared CBA/J mice during primary M.tb infection, Ag85 vaccination followed by M.tb challenge, or M.tb memory immune mice for their capacity to generate Ag85-specific IFN-γ responses and to control M.tb infection. CBA/J mice did not respond efficiently to Ag85 in the context of natural infection or re-infection. In contrast, CBA/J mice could generate Ag85-specific IFN-γ responses and protective immunity when this antigen was delivered as a soluble protein. Our data indicate that although M.tb infection of CBA/J mice does not drive an Ag85 response, these mice can fully and protectively respond to Ag85 if it is delivered as a vaccine. The data from this experimental model suggest that the Ag85-containing vaccines in clinical trials should protect M.tb susceptible humans.     

CpG-ODN及PolyICLC在结核亚单位疫苗中的佐剂效应

目的观察TLR识别配体不同组合佐剂对结核分枝杆菌融合蛋白免疫原性的影响及DDA对TLR识别配体的辅助效应。方法 CpG-ODN(CpG)和/或PolyICLC联合/不联合DDA,分别与融合蛋白Mtb10.4-HspX(MH)混合,制备亚单位疫苗,于第1、4、7周皮下免疫C57BL/6小鼠。以PBS和BCG(仅免疫1次)作为对照。末次免疫后6周,采血检测血清抗体水平,并分离脾淋巴细胞,检测分泌IFN-γ的淋巴细胞水平。结果经MH及HspX抗原刺激后,MH+CpG+PolyICLC+DDA组小鼠分泌IFN-γ的脾淋巴细胞数高于其它各组(P<0.05),MH+CpG+PolyICLC组其次,显著高于MH+CpG及MH+PolyICLC组(P<0.05);联合DDA佐剂组均分别高于对应的未联合DDA佐剂组(P<0.05)。各亚单位疫苗组诱导产生的抗MH及HspX的IgG1、IgG2b、IgG2c水平均明显高于BCG组(P<0.05),其中MH+CpG+PolyICLC+DDA组3种抗体水平最高;各亚单位疫苗组IgG2c/IgG1均高于BCG组(P<0.05)。结论 CpG+PolyICLC+DDA佐剂增强了结核分枝杆菌融合蛋白的免疫原性;CpG和PolyICLC具有佐剂协同作用;DDA有助于CpG和/或PolyICLC诱导特异性细胞免疫应答。     

结核融合蛋白AMM亚单位疫苗强化BCG初始免疫的免疫效应

目的 研究结核融合蛋白Ag85B-Mpt64190-198-Mth8.4(AMM)和佐剂二甲基三十六烷基铵(DDA)、卡介苗多糖核酸(BCG-PSN)构建的亚单位疫苗强化BCG初始免疫的免疫效应.方法 将融合蛋白AMM、佐剂DDA和BCG-PSN混合构建AMM亚单位疫苗.实验1组BCG初免后第10周用AMM亚单位疫苗加强免疫小鼠一次;实验2组BCG初免后分别于第8周、第10周用AMM亚单位疫苗加强免疫小鼠一次.同时设立生理盐水及仅BCG免疫两个对照组.BCG初免后第14周、第22周,应用ELISPOT、ELISA检测免疫小鼠的细胞及体液免疫反应.同时在第22周用BCG活菌攻击被免疫小鼠,间隔4周后用流式细胞术和ELISA技术检测T细胞分型及体液免疫反应.结果 (1)IFN-γ水平:BCG初免后14周,特异性抗原Ag85B刺激后实验2组分泌IFN-γ的细胞数(135±14)明显高于仅BCG免疫组(194±16),t=10.98,P<0.01;BCG初免后22周,实验2组(208±11)同样高于仅BCG免疫组(57±18),t=6.43,P<0.01.(2)体液免疫应答水平:实验2组的IgGI抗体滴度明显高于实验1组,而作为反映Th1型免疫反应指标的IgG2a/IgG1比值,强化免疫两次组低于强化一次组.(3)BCG模拟攻击被免疫小鼠后,CD4+CD25+调节性T细胞含量:实验1、2组均高于仅BCG免疫组(t1=3.08,t<2>=3.16,P<0.05).结论 BEG免疫-AMM亚单位疫苗加强免疫两次能够引起较强的细胞及体液免疫反应,同时激活调节性免疫反应.     

Immune response to Mycobacterium bovis bacille Calmette Guérin infection in major histocompatibility complex class I- and II-deficient knock-out mice: contribution of CD4 and CD8 T cells to acquired resistance

Knock-out mice with defined major histocompatibility complex (MHC) deficiencies were infected intravenously with Mycobacterium bovis bacille Calmette Guérin (M. bovis BCG) to assess the relative impact of MHC class I- and II-dependent immune responses. Heterozygous control mice were capable of controlling growth of M. bovis BCG, although infection progressed chronically, as assessed by determination of colony-forming units. Furthermore, infected controls developed granulomatous lesions at the site of mycobacterial growth and delayed-type hypersensitivity (DTH) reactions after challenge with purified protein derivative of tuberculin. In vitro, spleen cells from heterozygous control mice produced high concentrations of interferon-γ (IFN-γ) after restimulation with mycobacterial antigens. In contrast, the MHC class II-deficient Aβ^?/? mice, which are virtually devoid of functional CD4 T cells, succumbed to M. bovis BCG infection. Furthermore, Aβ^?/? mice lacked DTH reactions to tuberculin and only few minute picnotic lesions were formed in livers of infected mice. Finally, spleen cells from infected Aβ^?/? mice failed to produce measurable IFN-γ concentrations after restimulation in vitro with various mycobacterial antigen preparations. The capacity of β2-microglobulin (β2m)-deficient mice, which are devoid of CD8α/β T cells, to inhibit growth of M. bovis BCG was only slightly affected at low inocula, although significantly higher colony-forming units were detected in spleens. These knock-out mice developed strong DTH responses to tuberculin and their spleen cells produced high levels of IFN-γ once reactivated by mycobacterial antigens. Furthermore, in livers of infected β2m-deficient mice, extravascular infiltrates developed which were more diffuse than those in infected control littermates. Remarkably, the β2m-deficient mice were substantially more susceptible to higher inocula of M. bovis BCG than their control littermates. Our data formally prove the essential role of MHC class II-dependent immune mechanisms in all relevant aspects of immunity to M. bovis BCG. In addition, our findings emphasize an important contribution of MHC class I-dependent immunity to effective anti-mycobacterial protection. We assume that CD4 T cells are highly effective in containing M. bovis BCG within distinct granulomatous lesions, but fail to eradicate their intracellular pathogens. It appears most likely that CD8 T cells are also required to achieve this goal.     

卡介苗对hPBMC的TLR4表达调节及其免疫活化作用的研究

目的:了解卡介苗对人外周血单个核细胞( hPB-MC) TLR4的表达调节,以及BCG介导免疫细胞活化效应的新机制.方法:研究BCG对hPBMC的TLR4表达的调节,以及对表达TLR4的淋巴细胞的免疫活化效应,以(hPBMC+PBS)作为空白对照组,应用流式细胞仪对TLR4进行检测,ELISA方法测定BCG刺激组与对照组的IFN-γ和TNF-α的表达.结果:经过BCG刺激后,TLR4表达大大增加(P＜0.01),且随时间增加而增强,在72 h时,BCG组的TLR4表达率为(44.73±0.0066)％,而对照组的表达率仅为(1.02±0.0024)％.BCG可以促进淋巴细胞增殖,且这种增强作用也存在一定时间依赖性,在BCG与hPBMC共同孵育24h、48h和72h后,BCG组IFN-γ和TNF-α的表达量显著高于对照组(PBS组),差异有统计学意义(P＜0.05),且这种增强作用存在一定的时间依赖性.结论:BCG对hPBMC的TLR4表达有正调节作用,并加强表达TLR4的hPBMC的免疫活化作用.     

A novel recombinant BCG-expressing pro-apoptotic protein BAX enhances Th1 protective immune responses in mice

One-third of the world's population is infected with Mycobacterium tuberculosis (MTB). The protective efficacy of bacille Calmette Guérin (BCG) vaccine against tuberculosis (TB) in adults is highly controversial even though the BCG vaccine has been available for more than 90 years. Because BCG is effective against infantile tuberculosis meningitis and miliary tuberculosis in young children and provides cost-effective prevention from tuberculosis for developing countries, it would be desirable to modify the existing BCG vaccine to provide more comprehensive protection. In our study, we constructed a novel recombinant BCG strain expressing pro-apoptotic BAX (rBCG::BAX) and demonstrated that it significantly induced the apoptosis of macrophages infected with rBCG::BAX both in vitro and in vivo. In addition, it significantly enhanced Ag85B-specific IFN-γ enzyme-linked immunospot responses, IFN-γ secretion, IL-2 secretion and the ratio of Ag85B-specific IgG2b/IgG1, and it significantly decreased Ag85B-specific IL-4. Furthermore, it presumably facilitated antigen presentation by inducing a significant up-regulation in the expression of MHC-II and B7.1 (CD80) co-stimulatory molecules on macrophages. In conclusion, these results suggest that the rBCG::BAX strain elicited predominantly a Th1 protective immune responses and might be a potential tuberculosis vaccine candidate for further study.     

卡介苗(BCG)通过诱导IL-12产生和受体表达促进人NK细胞功能

目的:研究卡介苗(BCG)对人自然杀伤细胞(NK)功能的作用及其机制.方法:分离抗结核抗体阴性志愿者外周血PBMC、纯化NK细胞, 分别与BCG、 IL-12、 BCG+IL-12、 BCG+抗IL-12Rβ1 mAb(2B10)培养.利用ELISA方法检测培养上清液IFN-γ、 IL-12p40含量;利用ELISpot方法检测IFN-γ、颗粒酶B产生细胞的频率;利用四甲基偶氮唑盐(MTT)比色法测定杀伤功能.利用流式细胞术检测NK细胞IL-12Rβ1的表达.结果:BCG呈剂量依赖的方式诱导PBMC产生IFN-γ.在BCG刺激条件下, PBMC颗粒酶B分泌细胞数明显高于不加任何刺激剂组(P<0.05).BCG增强PBMC杀伤活性.BCG不能诱导纯化NK细胞产生IFN-γ, 但与IL-12同时刺激则表现出协同作用.纯化NK细胞经BCG刺激后杀伤活性与未刺激相比差异无统计学意义.BCG呈剂量依赖方式诱导PBMC产生IL-12、并促进NK细胞不同亚群表达IL-12Rβ1.2B10抗体抑制BCG对PBMC产生IFN-γ和分泌颗粒酶B的诱导作用.结论:BCG间接地促进NK细胞的生物学活性, 其部分机制是通过诱导单核细胞产生内源性IL-12、并上调NK细胞表达IL-12R.     

壳聚糖递送的结核基因疫苗诱导的肺部黏膜免疫及在抗结核免疫保护中的意义

诱导肺局部黏膜免疫对于早期控制结核分枝杆菌(Mycobacterium tuberfulosis)十分关键.在我们过去构建的结核基因疫苗pHSP65pep有效诱导脾脏IFN-γ+Th1细胞应答的基础上,为更好诱导呼吸道和肺局部黏膜免疫,采用天然生物多糖壳聚糖(chitosan)作为黏膜递送介质递送结核基因疫苗.制备壳聚...