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1.
目的:利用噬菌体展示技术,构建人源抗狂犬病毒单链抗体库,筛选特异性的抗狂犬病毒糖蛋白人源单链抗体(scFv)并对其进行初步鉴定。方法:从接种狂犬疫苗的志愿者外周血中提取总RNA,RT-PCR扩增VH和VL基因,并利用重叠扩增PCR将VH和VL拼接为scFv。将纯化后的scFv克隆至噬菌体载体pComb3XSS构建人源抗狂犬病毒单链抗体库,以狂犬病毒糖蛋白(RABVG)为抗原,从抗体库中筛选抗RABVG的scFv。通过phage-ELISA验证噬菌体单链抗体的结合特异性,将阳性克隆转化E.coliTOP10F′进行表达。结果:构建了人源抗狂犬病毒抗体库,抗体库的库容为3.29×109。经过5轮筛选,获得43株与RABVG特异结合的噬菌体单链抗体,其中15个A450值较高的克隆序列分析结果显示,有3个正确的单链抗体基因。单链抗体基因转化TOP10F′构建工程菌,表达纯化后的单链抗体,经ELISA检测能够与RABVG特异性结合。结论:从构建的人源免疫型抗狂犬病毒单链抗体库筛选出的能与RABVG特异性结合的scFv,为进一步制备抗RABVG的治疗性人源化抗体奠定了基础。  相似文献   

2.
目的:构建全人源抗狂犬病病毒scFv噬菌体抗体库,筛选针对狂犬病病毒G蛋白不同表位的单链抗体(scFv)并鉴定其中和活性?方法:分离130例经狂犬病疫苗免疫接种志愿者的外周血淋巴细胞,提取总RNA,逆转录制备cDNA,构建全人源抗狂犬病病毒scFv噬菌体抗体库?以纯化的狂犬病病毒G蛋白包板筛选,对阳性克隆进行可溶性表达,并鉴定中和活性?结果:构建全人源抗狂犬病病毒scFv噬菌体抗体库,库容为5.0 × 107,经核酸序列分析,证实插入片段为scFv?经过5轮筛选,从富集的次级抗体库中随机挑出140个克隆,通过phage-ELISA鉴定得到4株核酸序列不同的scFv抗体?经His-Trap纯化后进行中和活性鉴定,获得1株有中和活性的scFv,其中和效价为0.13 IU/mg?结论:构建全人源抗狂犬病病毒scFv噬菌体抗体库,获得1株具有中和活性的抗狂犬病病毒G蛋白scFv抗体,为进一步研发狂犬病治疗性抗体药物奠定了基础?  相似文献   

3.
目的从大容量噬菌体抗体库中筛选人源性抗角蛋白单链抗体(scFv),测定其特异性结合活性并进行基因序列分析。方法以混合分子量人表皮角蛋白包被固相,对构建的大容量噬菌体抗体库进行筛选,经4轮“吸附洗脱扩增”后,挑取单克隆,用ELISA法测定特异性结合活性,并对阳性克隆抗体基因进行DNA指纹分析及序列同源性分析。结果经4轮筛选,获得9株可表达抗人角蛋白单链抗体的克隆,酶切鉴定正确后,经DNA指纹分析及序列同源性分析证明为不同的抗体基因。结论利用噬菌体抗体库技术获得了人源性抗角蛋白单链抗体,为临床应用研究提供了具有更广阔应用前景的人源小分子抗体。  相似文献   

4.
目的:获得人源性乙型肝炎病毒抗HBs轻链基因.方法:从已构建的人源性噬菌体抗体库中,用固相化HBs/Ag对构建的人源性噬菌体抗体库进行三轮淘筛,经ELISA实验,筛选到抗HBs噬菌体抗体(P/N:2.415)的阳性克隆,根据已知序列合成一对轻链引物,进行PCR扩增,扩增出轻链目的基因片段,将目的基因片段定向克隆入质粒pUC18,进行序列测定及分析.结果:筛选出的克隆具有HBsAg特异性亲和力,构建了pUCl8-抗HBsk链重组质粒,序列分析其为κ链,为643bp包括了可变区和恒定区.结论:利用抗原抗体特异性反应从噬菌体抗体库中筛选到抗HBs轻链基因.  相似文献   

5.
从噬菌体抗体库中筛选D二聚体特异的Fab抗体   总被引:1,自引:0,他引:1  
目的:从人源性噬菌体抗体库中筛选抗人D二聚体单克隆抗体并进行可溶性表达。方法:以人D二聚体标准品为抗原对所构建的噬菌体抗体库进行两轮“吸附-洗脱-扩增”筛选,从中筛选出抗人D二聚体的噬菌体Fab抗体,并在大肠杆菌细胞中进行可溶性表达。结果:经4次电转化构建了库容为2. 8×108cfu的抗体库,滴度为4. 1×1014PFU/mL,Fab基因重组率为46%。经过淘筛后携带抗人D二聚体抗体的特异性噬菌体得到了明显的富集。用试剂盒以ELISA法检测对人D二聚体的结合活性,得到抗人D二聚体单克隆抗体。筛选出的阳性克隆成功在大肠杆菌细胞中可溶性表达筛选出的阳性克隆在大肠杆菌细胞中可溶性表达。结论:人D二聚体标准品对抗体库的淘筛,富集了表面呈现抗人D二聚体的单克隆抗体的噬菌体,成功构建了人源性抗D二聚体噬菌体抗体,并成功在大肠杆菌细胞中可溶性表达。  相似文献   

6.
目的 筛选具有较好结合能力的抗木瓜凝乳蛋白酶单链抗体(scFv),并进行可溶性表达和鉴定.方法 前期实验室构建了抗木瓜凝乳蛋白酶全套鼠源scFv噬菌体抗体文库,对抗体文库进行4轮富集后,采用ELISA筛选抗木瓜凝乳蛋白酶阳性scFv;将ELISA最强阳性克隆pFAB5C-scFv的重组噬粒切除gene 3 singal后进行表达,SDS-PAGE分析、双抗体夹心ELISA分析、鉴定表达产物,并将阳性克隆可变区序列与Gene Bank数据库进行同源性比较.结果 经4轮噬菌体展示富集,筛选到3株亲和力相对较高的阳性克隆;去除gene 3 singal后的重组scFv在宿主菌E.coli XL1-blue中主要以可溶性的形式进行了表达,且对木瓜凝乳蛋白酶有较好的亲和力.基因序列分析表明阳性克隆所包含的重链可变区基因(VH)与小鼠免疫球蛋白γ重链基因同源性达96%,轻链可变区基因(VL)和小鼠免疫球蛋白轻链κ基因同源性达98%.结论 成功筛选出结合能力较好的抗木瓜凝乳蛋白酶scFv并进行了可溶性表达,所克隆的scFv基因符合小鼠抗体序列的特征.  相似文献   

7.
噬菌体抗体库的构建及抗肝癌抗体的筛选   总被引:1,自引:0,他引:1  
目的 构建噬菌体抗体库及筛选抗人肝癌特异性噬菌体抗体。 方法 以RT-PCR法从经Bel7404细胞免疫的BALB/C小鼠脾淋巴细胞扩增免疫球蛋白的Fd 段及к链基因,克隆到表达载体pCOMB3H-SS中并将抗体Fab 段表达于单链噬菌体表面,构建噬菌体抗体库;以Bel7404细胞为抗原对噬菌体抗体库进行4轮“吸附-洗脱-扩增”的亲和筛选,挑取部分克隆检测与抗原的结合活性。 结果 建成容量为2×106CFU 的噬菌体抗体库,在亲和筛选过程中,噬菌体收获率逐轮得到提高,第4轮为第一轮的245 倍,含Fab 基因的克隆比率也由26% 增到83% ,挑取的10 个克隆中有8 个与Bel7404细胞有结合活性。 结论 噬菌体抗体库技术系高效筛选体系,为肿瘤单克隆抗体的制备提供了有效的途径  相似文献   

8.
目的构建抗表皮生长因子受体Ⅲ型突变体(EGFRvⅢ)特异性单链抗体库,从中筛选抗EGFRvⅢ特异性单链抗体。方法用pep-3偶联载体蛋白OVA,然后免疫BALB/c小鼠从脾淋巴细胞中提取总RNA,采用RT-PCR方法扩增重链(VH)和轻链(VL)的可变区基因片段。将两基因片段由编码(Gly4Ser)3的linker连在一起,并克隆入噬菌体展示表达载体pCANTAB5E中,电转化至E.coliTG1,经辅助噬菌体超感染,构建噬菌体单链抗体库。以pep-3-BSA为抗原对所建抗体库进行4轮亲和筛选,用ELISA鉴定抗体与EGFRvⅢ结合的特异性。结果经琼脂糖凝胶电泳分析,RT-PCR方法扩增的抗体VH和VL基因片段大小约350和320bp,与预期理论值相符。经重组PCR得到大小约780bp的ScFv基因片段。ScFv基因片段经双酶切后成功定向克隆到噬菌粒载体,回收后构建成库容量为5.0×106的噬菌体抗体库,噬菌体滴度为3.0×104pfu/ml。通过亲和筛选使抗EGFRvⅢ噬菌体单链抗体得到富集,第4轮为第1轮的56倍。在E.coliHB2151中实现了单链抗体的可溶性表达。SDS-PAGE结果显示抗体相对分子...  相似文献   

9.
王刚  刘玉峰  王琰 《医学争鸣》2001,22(24):2223-2225
目的:克隆制备人源性抗角蛋白IgM抗体。方法:以人表皮角蛋白为抗原,从人源性天然抗体库中筛选IgM型抗角蛋白人抗体,并用ELISA对所获抗体进行抗原结合活性和特异性等鉴定。结果:通过3轮“亲和吸附-洗脱-扩增”筛选,获得2株IgM型抗角蛋白噬菌体抗体。酶切去掉载体上的噬菌体基因Ⅲ,得到 了可溶性表达的Fab段。经过鉴定,所获抗体具有良好的抗原结合活性和特异性。结论:从人源性天然抗体库中成功筛选出2株抗角蛋白IgM抗体,为进一步研究抗角蛋白抗体的特性提供了条件。  相似文献   

10.
目的:制备人源性抗核抗体Fab片段.方法:通过4轮淘筛,富集已构建的人源性抗核抗体Fab片段噬菌体抗体库,间接ELISA法鉴定4轮淘筛后抗核抗体Fab片段噬菌体抗体;提取阳性克隆的噬菌粒DNA,切除gⅢ基因片段,自连接后转化大肠杆菌XL1-Blue,以IPTG诱导表达可溶性人源性抗核抗体Fab片段;应用间接ELISA法及荧光免疫法对表达上清进行鉴定.结果:第4轮洗脱的噬菌体滴度较第1轮增加200条倍,从抗核抗体Fab片段噬菌体库中筛选出2株阳性克隆,切除gⅢ基因后自连的噬菌粒DNA经XhoⅠ单酶切证实连接成功.间接ELISA法检测结果显示:制备的可溶性人源性抗核抗体Fab片段均呈现抗dsDNA阳性,具有抗原特异性;免疫荧光法结果显示:Hep2细胞和猴肝脏组织细胞核显示均质型荧光,绿蝇短膜虫的动基体显示均质型荧光.结论:成功制备具有抗原特异性的可溶性、人源性抗核抗体Fab片段,为高亲和力抗核抗体Fab片段的制备奠定了基础.  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

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