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1.
SARS冠状病毒N蛋白的表达及其诱导的免疫应答   总被引:1,自引:0,他引:1  
目的表达和纯化SARS冠状病毒的N蛋白,分析其诱导的免疫应答。方法从重组克隆pMD18-N中切取N基因的插入片段,亚克隆至原核表达质粒pET-23a(+)中,转化大肠杆菌BL21,PCR和酶切鉴定转化菌落的插入序列;将构建的原核表达菌株经IPTG诱导,SDS-PAGE分析重组蛋白的表达;大量诱导表达N蛋白,金属螯合层析予以纯化,将纯化蛋白免疫小鼠,观察其诱导的免疫应答。结果N基因的特异片段被亚克隆到原核表达质粒pET-23a(+),在大肠杆菌表达了SARS冠状病毒的N蛋白;表达的蛋白经金属螯合层析获得纯化;纯化蛋白能被重组N蛋白的GST融合蛋白的免疫血清识别,并诱导小鼠产生了高滴度的抗体和Th1/Th2型的免疫应答。结论成功构建了N蛋白的原核重组表达质粒,纯化的蛋白具有良好的抗原性。  相似文献   

2.
目的用构建的微小隐孢子虫Cpgp40/15基因真核表达重组质粒免疫BALB/c小鼠,观察其诱导的细胞及体液免疫反应,为研究高效的微小隐孢子虫基因疫苗提供理论依据。方法用碱裂解法大量制备pVAX1-Cpgp40/15真核表达重组质粒,经肌肉注射和滴鼻两种途径免疫BALB/c小鼠,每鼠注射100,ug(质粒与佐剂重量体积比为1:0.5),2周后同量加强免疫1次,分别于免疫后15、30、45d尾静脉采血,用流式细胞仪测定T淋巴细胞亚群数目,ELISA法测定IgG抗体滴度。实验设有pVAX1空质粒、C.parvum卵囊及生理盐水对照组。结果用pVAX1-Cpgp40/15质粒免疫BALB/c小鼠30d后,血液中T淋巴细胞数目和抗体滴度发生明显变化,主要表现为CD4^ 和CD8^ 细胞数增加,CD4^ /CD8^ 比值下降;攻击感染隐孢子虫后,免疫组小鼠血液CD4^ /CD8^ 比值下降更显著,血清IgG抗体水平(30d内)显著升高,粪检虫卵数显著减少。结论用pVAX1-CPgP40/15重组质粒DNA免疫小鼠,可诱导机体发生细胞及体液免疫应答,产生一定的免疫保护力。  相似文献   

3.
目的对犬瘟热病毒(CDV)弱毒株M基因进行克隆及原核表达,并制备鼠抗CDV M蛋白多克隆抗体。方法针对犬瘟热病毒弱毒株(CDV-LP)的M基因序列设计引物,用反转录-聚合酶链式反应(RT-PCR)扩增目的基因片段,扩增产物克隆至表达载体pET-30a(+)并转化至宿主菌BL21(DE3),在0.4mmol/L IPTG和37℃条件下诱导表达目的蛋白,经Ni-NTA亲和层析纯化后进行SDS-PAGE和Western blot鉴定。以纯化的M蛋白免疫BALB/c小鼠,经3次免疫后采血,分离血清,制备鼠抗CDV M蛋白多克隆抗体。结果通过RT-PCR成功扩增出大小为1 014bp的CDV M基因,构建的重组质粒pET-30a(+)-M在大肠埃希菌中诱导表达出分子质量单位为43ku的重组M蛋白,与预期值相符;重组蛋白主要以包涵体形式表达,Western blot检测显示M重组蛋白能被抗CDV多克隆抗体识别;免疫小鼠制备的多抗能与纯化的重组蛋白发生特异性反应。结论本研究成功构建了pET-30a(+)-M并表达了CDV M蛋白,制备了鼠多克隆抗体,为建立CDV M蛋白的ELISA抗原检测方法,鉴定表达M蛋白的重组杆状病毒奠定了基础。  相似文献   

4.
目的构建表达HCV非结构蛋白3(NS3)的重组腺病毒RAd/NS3,探讨其免疫小鼠后诱导机体产生特异性免疫应答的能力。方法PCR扩增编码NS3蛋白(329~935位氨基酸)的基因片段,定向克隆至重组腺病毒AdEasy-1系统的穿梭质粒pAdTrack-CMV上,与腺病毒基因组质粒pAdEasy-1共转化BJ5183菌,利用细菌内同源重组获得重组腺病毒质粒,转染293细胞,以包装、扩增重组腺病毒。将重组腺病毒以1×10^8 pfu剂量经皮下注射免疫BALB/c小鼠,并以100μg重组质粒pRC/NS3经肌内注射途径免疫小鼠为对照。ELISA法检测免疫小鼠血清抗体水平,^51 Cr释放法检测免疫小鼠细胞毒性T淋巴细胞体外杀伤功能。结果重组腺病毒经皮下免疫小鼠后可刺激机体产生较强的特异性体液免疫应答和细胞免疫应答,且免疫效果强于重组质粒pRC/NS3组,初次免疫后2周,前者20只小鼠抗-HCV全部阳转,而后者10只小鼠仅3只阳转,未观察到明显的不良反应。结论表达HCV NS3抗原的重组腺病毒载体疫苗能够诱导机体产生有效的体液和细胞免疫应答。  相似文献   

5.
目的 探讨以恶性疟原虫富组氨酸蛋白 2 (PfHRP2 )为基础的不同形式的侯选疫苗诱导小鼠免疫应答的特性 ,为包含HRP2的恶性疟红内期疫苗的研制提供实验依据。方法 用重组蛋白TP HRP2及真核表达质粒pcDNA3 1(- ) HRP2免疫BALB c小鼠 ,对抗体应答的动力学及特异性进行分析 ,取脾细胞进行体外增殖实验 ,用免疫血清进行P f.体外生长抑制实验。结果 重组蛋白TP HRP2加福氏佐剂诱导BALB c小鼠产生了高水平的抗体 ,其抗体产生快、持续时间久 ,并具较高的特异性 ,细胞应答被同期激活 ,免疫血清可明显抑制红细胞内发育期疟原虫。重组真核表达质粒pcDNA3 1(- ) HRP2诱导BALB c小鼠产生了较高水平和具有一定特异性的抗体 ,其抗体的产生需要多次免疫和较长时间 ,初始化的脾细胞对抗原再刺激的回忆应答显著 ,但免疫血清对疟原虫的体外生长没有抑制作用。结论 HRP2重组蛋白与真核表达质粒在小鼠具有较为不同的免疫特性 ,HRP2重组蛋白疫苗具有潜在的应用前景  相似文献   

6.
目的构建淋病奈瑟球菌表面蛋白A(NspA)基因疫苗,并接种小鼠,评价其诱导的体液和细胞免疫应答。方法将NspA基因插入到真核表达载体pcDNA3.1(+)中,构建重组真核表达质粒pcDNA3.1(+)/NspA,并经PCR、双酶切及测序鉴定。反转录一聚合酶链反应(RT-PCR)和免疫组织化学法分别检测NspA基因转染细胞后mRNA和蛋白的表达。以pcDNA3.1(+)/NspA重组质粒免疫45只雄性BALB/c小鼠,试管凝集法检测免疫小鼠抗体滴度,ELISA检测IFN-γ水平,四甲基偶氮唑蓝(MTT)比色法检测脾淋巴细胞增殖。提取接种部位股四头肌总DNA,PCR检测BALB/c小鼠肌细胞内NspA基因。结果成功构建pcDNA3.1(+)/NspA基因疫苗,能在真核细胞中转录和表达。pcDNA3.1(+)/NspA免疫组的抗体滴度达1:640,pcDNA3.1(+)和PBS免疫组均无特异性抗体检出。空载体pcDNA3.1(+)组IFN-γ为(23.79±11.85)pg/mL,pcDNA3.1(+)/NspA免疫组为(169.71±30.52)pg/mL(P〈0.01);脾淋巴细胞增殖的刺激指数(SI)分别为1.05±0.30和1.94±0.74(P〈0.01)。并证实NspA基因可在小鼠肌细胞中稳定存在。结论构建淋病奈瑟球菌NspA基因疫苗,将其免疫BALB/c小鼠可诱导特异性体液和细胞免疫应答,为进一步用于淋病预防奠定了基础。  相似文献   

7.
目的构建分泌性表达布鲁氏菌外膜蛋白OMP25基因重组卡介苗(rBCG-omp25),并免疫BALB/c小鼠,观察其免疫作用。方法利用分子生物学技术构建重组穿梭分泌载体pMV261-Ag85B-omp25.电穿孔技术导人卡介苗(BCG)。通过抗生素筛选、重组卡介苗基因组PCR扩增、测序,以及Western blot对重组卡介苗进行鉴定。分别用rBCG-omp25、BCG腹腔接种BALB/c小鼠,于免疫后第10、20、30、40和50d称重,尾部采血,用表达纯化的融合蛋白OMP25—32a检测免疫小鼠抗体的生成情况,用流式细胞仪(FCM)检测CD4^+、CD8^+T淋巴细胞百分率,并计算CD4^+/CD8^+T细胞比值。制作小鼠肝组织切片,HE染色观察病理学变化。结果重组卡介苗rBCG-omp25含有Ag85B-omp25序列,大小为745hp;Western blot表明rBCG-omp25可分泌表达布鲁氏菌OMP25。rBCG-omp25免疫小鼠后第20d,用Western blot检测到布鲁氏菌OMP25特异性抗体;rBCG—omp25免疫组和BCG免疫组的CD4^+、CD8^+T细胞百分率分别为38.68%、11.32%和、48.44%、14.01%,PBS组为33.24%、9.81%,差异有统计学意义(P〈0.05)。免疫后50d内rBCG-omp25组、BCG组与PBS组小鼠体重差异无统计学意义(P〉0.05);各实验组小鼠肝组织均未见明显病理改变。结论构建的rBCG-omp25能够表达特异性蛋白OMP25。该蛋白能刺激小鼠产生特异性抗体,能刺激小鼠外周血CD4^+、CD8^+T淋巴细胞增殖。rBCG-omp25毒力弱,可作为预防布鲁氏菌病的疫苗候选株之一。  相似文献   

8.
目的构建SARS冠状病毒(SARS-CoV)小囊膜蛋白(E蛋白)的DNA疫苗pVAC-E,观察其在小鼠中诱导的免疫应答。方法采用PCR方法体外扩增SARS冠状病毒E蛋白的基因片段,克隆入真核表达载体pVAC,构建pVAC-E重组质粒。通过脂质体介导瞬时转染非洲绿猴肾(Vero)细胞,Western-blot鉴定E蛋白在细胞中的表达。以基因枪方式免疫小鼠,ELISA检测小鼠血清特异性抗体,MTT法测定淋巴细胞转化率,流式细胞仪检测小鼠脾脏T淋巴细胞亚群分布。结果成功构建SARS-CoVDNA疫苗pVAC-E。Western-blot结果示,转染后的Vero细胞可表达一约9kD大小能被SARS病人血清特异识别的蛋白条带。免疫小鼠中未检测到明显的抗体滴度升高。淋巴细胞转化率在免疫组和对照组间无差别(P>0.05)。脾脏T淋巴细胞亚群分析示免疫组小鼠CD4+细胞显著升高(P<0.05),CD8+细胞与对照组相比无显著差异。结论构建的真核表达质粒pVAC-E能在Vero细胞中表达,表达产物具免疫活性,免疫小鼠后能诱导一定的细胞免疫应答。  相似文献   

9.
目的观察黏蛋白1两串联重复区(MUC1-2VNTR)基因疫苗诱导BALB/c小鼠体液及细胞免疫应答的效果。方法将含MUC12VNTR的重组质粒peDNA3.1-2VNTR/myc-hisB免疫小鼠,免疫后采用ELISA动态检测血清中抗VNTR特异性抗体的水平,乳酸脱氢酶法检测细胞毒性T细胞(CTL)反应活性,MTS法检测脾淋巴细胞增殖活性。结果重组质粒免疫组小鼠血清中检出了MUC1-2VNTR抗原特异性抗体。用重组质粒免疫BALB/c小鼠后,在效靶比为80:1时可显著地诱导特异性CTL应答。在MUC1-2VNTR抗原肽的刺激下,免疫小鼠脾淋巴细胞得到增殖;与空质粒对照组比较,差异有统计学意义(P〈0.01)。结论MUC1-2VNTR基因疫苗可诱导小鼠产生特异性细胞及体液免疫应答,对多发性骨髓瘤的疫苗治疗有重要意义。  相似文献   

10.
本文利用恶性疟原虫FCC1/HN株环子孢子蛋白 (PfCSP)基因DNA质粒通过不同途径、不同剂量免疫小鼠 ,观察其产生的体液免疫应答反应 ,并将其与相应的重组表达蛋白疫苗进行比较。结果显示 :DNA免疫刺激机体产生抗体反应强度的免疫途径依次为肌肉、静脉和皮下 ;宿主对DNA免疫存在一定的剂量依赖性 ;ELISA和Dot -ELISA检测免疫后 4周和 7周 ,DNA质粒组刺激机体产生抗体的滴度均显著低于相应的重组蛋白组。表明PfCSPDNA疫苗与重组表达蛋白疫苗均可刺激小鼠产生特异性体液免疫应答 ,但前者诱导高滴度的抗体反应需要更长的时间  相似文献   

11.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

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Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.  相似文献   

14.
Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

15.
Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.  相似文献   

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Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the Mr range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [125I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (Ka of 4.7 ± 0.2 × 109 M-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of Mr 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.  相似文献   

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PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.  相似文献   

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