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1.
目的探讨大肠杆菌表达的卵巢癌抗独特型单链抗体/小鼠热休克蛋白70(6811ScFv/mHSP70)融合蛋白包涵体变性、复性条件,以确定其最佳体外复性条件。方法大肠杆菌表达大量融合蛋白6811ScFv/mHSP70:①比较不同的裂解液(8mol/L尿素和6mol/L盐酸胍)对包涵体的裂解效率及其对复性蛋白活性的影响;②探索序贯稀释方法,以及氧化还原环境和复性液中不同浓度L-精氨酸对蛋白稀释复性的影响;③比较稀释复性和柱。卜复性对融合蛋白复性效率及活性的影响。采用Bradford法测定包涵体裂解液与复性后蛋白浓度。所有复性蛋白活性的检测均采用ELISA方法。结果以包涵体形式表达6811ScFv/mHSP70蛋白:①经6mol/L盐酸胍裂解包涵体的效率远高于8mol/L尿素,但前者复性所得蛋白活性低,6mol/L盐酸胍彻底裂解的包涵体经8mol/L尿素透析后再复性,复性效率显著提高;②序贯稀释方法可提高蛋白复性效率;加入0.5mol/L L-精氨酸可降低稀释复性过程中蛋白聚集物的产生,提高复性效率;加入还原型谷胱甘肽(GSH)与氧化型谷胱甘肽(GSSH)浓度比为1:5时,可提高复性后蛋白活性;③柱上复性可一步完成蛋白的复性和纯化,所得蛋白纯度较高,但复性效率和复性后蛋白活性较稀释复性低。结论本研究建立了6811ScFv/mHSP70融合蛋白的最佳复性条件:包涵体经6mol/L盐酸胍彻底裂解后,再经8mol/L尿素透析,然后进行序贯稀释复性,且复性液中加入0.5mol/L L-精氨酸和GSH:GSSH=1:5以提高复性效率和蛋白活性,为进一步研究该蛋白的功能奠定了基础。  相似文献   

2.
用聚合酶链反应(PCR)从人源噬菌体抗体库中筛选出的宋内痢疾杆菌脂多糖抗独特型抗体基因扩增了重链可变区基因,将其克隆到表达载体pGEX2T内,转化大肠杆菌DH5α,获得高效表达,表达量占全菌总蛋白质的40%左右,表达出的融合蛋白分子量为4×104,以包涵体形式存在。将此融合蛋白包涵体变性、复性后通过谷胱甘肽亲和层析柱(GSTSepharose4B柱),得到电泳纯的融合蛋白,每升培养物能纯化到20~30mg融合蛋白。Westernblot分析证明宋内痢疾杆菌脂多糖鼠单抗(5B12)能特异地结合到分子量4×104的融合蛋白的带上。ELISA试验显示融合蛋白与宋内痢疾杆菌脂多糖单抗(5B12)有结合活性,而与无关单抗,如大肠杆菌J5株单抗(E3)、炭疽杆菌单抗(F8FA)、鼠伤寒沙门氏菌单抗(M467)及乙肝病毒单抗(M11)不结合。  相似文献   

3.
成军  钟彦伟 《免疫学杂志》2000,16(4):246-249
目的筛选、鉴定抗丙型肝炎病毒 (HCV)非结构蛋白 NS3的人单链可变区抗体 (Sc Fv) ,以解决人体内应用鼠单抗时的免疫原性问题 ,为进行抗 HCV的基因治疗研究开辟新途径。方法采用噬菌体表面展示技术 ,以重组的 HCV非结构蛋白 NS3为固相抗原 ,从噬菌体单链可变区抗体库中经过 5轮“吸附 -洗脱 -扩增”筛选过程 ,获得抗原结合活性较强的 HCVNS3人单链可变区抗体的阳性克隆 ,并对其进行免疫检测及序列测定。结果筛选出来的 Sc Fv片段具有抗 NS3的特异性。证实利用噬菌体抗体库技术 ,可以成功地获得 HCV NS3人单链抗体 Sc Fv的编码基因。结论筛选获得了 HCV非结构蛋白 NS3的特异性单链抗体的编码基因。  相似文献   

4.
huIL-6-GM-CSF(9-127)融合蛋白的表达及活性测定   总被引:1,自引:2,他引:1  
目的 构建及表达具有huIL 6和huGM CSF双重生物学活性的huIL 6 GM CSF(9- 12 7)融合蛋白分子。方法 应用PCR技术对huIL 6和huGM CSF的基因分别加以改造 ,同时在二者之间加上连接肽序列 (G G S G S) 3 ,克隆PCR产物 ,并构建成pBV2 2 0 IL 6 GM CSF(9- 12 7)表达质粒 ,将表达质粒导入E .coliDH5α中 ,诱导表达融合蛋白。通过QSepharoseH .P .离子交换柱和SephacrylS 2 0 0分子筛柱二步柱纯化以获取目的蛋白。使用MTT法测量其huIL 6和huGM CSF生物学活性。结果 pUC18 IL 6 GM CSF(9- 12 7)的序列与理论设计完全一致 ,表达质粒在E .coliDH5α中得到高效表达 ,表达的融合蛋白占总蛋白含量的 30 %以上 ,表达产物以包涵体的形式存在。通过QSepharoseH .P .离子交换柱和SephacrylS 2 0 0分子筛柱二步柱纯化及复性后获得目的蛋白 ,其纯度达到 96 %以上。融合蛋白具有huIL 6和huGM CSF的双重生物学活性 ,其促进huIL 6依赖细胞株B9和huGM CSF依赖细胞株TF 1增殖的比活性分别为 2 .86× 10 7U/mg和 3.33× 10 8U/mg。结论 获得了具有较高纯度和双重生物学活性的huIL 6 GM CSF(9- 12 7)融合蛋白  相似文献   

5.
目的 :构建及表达具有hIL 6和hGM CSF双重生物学活性的hIL 6 /GM CSF融合蛋白分子。方法 :应用PCR技术对hIL 6和hGM CSF的基因分别加以改造 ,同时在两者之间加上连接肽序列 (G G S G S) 3 ,克隆PCR产物 ,并构建成克隆有两种融合蛋白基因的pBV2 2 0表达质粒 ,两种融合蛋白分别是 :IL 6 (1~ 184 ) GM CSF(9~ 12 7) (简称IG1)和IL 6 (2 4~ 184 ) GM CSF(9~ 12 7) (简称IG2 )。将表达质粒分别导入E .coliBL 2 1中诱导表达。通过QSepharoseHP离子交换柱和SephacrylS 2 0 0分子筛柱二步柱纯化目的蛋白。使用hIL 6依赖细胞株B9和hGM CSF依赖细胞株TF1,通过MTT比色法测定融合蛋白的生物学活性。结果 :对两种融合蛋白基因的测序结果表明 ,其序列与理论设计完全一致。表达质粒在E .coliBL 2 1中均得到高效表达 ,表达的融合蛋白均占总蛋白含量的 2 5 %以上 ,表达产物以包涵体的形式存在 ,通过QSepharoseHP离子交换柱和SephacrylS 2 0 0分子筛柱二步柱纯化及复性后 ,获得两种目的蛋白 ,其纯度均达到 95 %以上。活性测定结果表明 ,两种融合蛋白均具有较高的hIL 6和hGM CSF的双重生物学活性。结论 :获得了具有较高纯度和双重生物学活性的hIL 6 /GM CSF融合蛋白  相似文献   

6.
目的:人工设计并表达美罗华(C2B8)单链可变区抗体与李斯特菌溶细胞素O(Listeriolysin O,LLO)显性抗原表位构成的重组融合蛋白(Sc Fv-p LLO),初步分析其抗淋巴瘤细胞活性。方法:查询数据库获得美罗华(C2B8)单抗VH和VL基因序列,构建抗CD20单链抗体(Sc Fv)基因序列,选取LLO的2个CD4+T细胞表位,构建单链抗体融合抗原表位的重组蛋白基因序列,克隆至原核表达载体,经诱导表达纯化,流式细胞术和免疫共沉淀分析其与淋巴瘤细胞结合能力,细胞增殖实验测定其对淋巴瘤细胞生长的影响,凋亡实验分析其诱导淋巴瘤细胞凋亡的能力,淋巴细胞增殖实验分析其免疫原性。结果:成功诱导表达重组蛋白Sc Fv-p LLO。Sc Fv-p LLO可不同程度地靶向结合不同淋巴瘤细胞系,并明显抑制Raji细胞生长和诱导其凋亡。Sc Fv-p LLO可刺激免疫小鼠脾细胞增殖。结论:重组蛋白Sc Fv-p LLO保留了Sc Fv的功能,可靶向结合和抑制CD20阳性淋巴瘤细胞的生长,同时可激活机体免疫应答,为进一步研究其模拟瘤细胞表面抗原和作为瘤细胞疫苗佐剂的功能奠定基础。  相似文献   

7.
 目的 构建卵巢癌抗独特型单链抗体 6B11ScFv 与小鼠热休克蛋白 70(mHSP70)融合蛋白 6B11ScFv/mHSP70,并初步鉴定其免疫活性。 方法 根据 Genebank 上已发表的 mHSP70 基因序列(NM_010478)合成引物行 PCR 扩增,以扩增所得 mHSP70 基因插入 pET30a(+)-6B11ScFv 质粒后转化入 E.coli DH5α,获得 pET30a(+)-6B11ScFv/mHSP70 重组质粒。将鉴定正确的 pET30a(+)-6B11ScFv/mHSP70 重组质粒转化入 E.coli BL21(DE3),获得 E.coli BL21(DE3)[pET30a(+)-6B11ScFv/mHSP70]重组菌株。以异丙基-β-D-硫代半乳糖苷(IPTG)诱导表达并行 SDS-PAGE 分析,对表达产物进行复性和 Ni2+-NTA 柱亲和层析纯化后,采用蛋白质印迹法和 ELISA 方法进行鉴定和免疫活性检测。 结果 6B11ScFv/mHSP70 融合基因测序结果基本与理论序列相符。SDS-PAGE 分析显示,重组菌株表达产物相对分子质量与预期相符。复性、亲和层析纯化后的蛋白复性率达 20.9%,蛋白纯度达 95% 以上。蛋白质印迹分析证实 6B11ScFv/mHSP70 融合蛋白相对分子质量为 104 000,ELISA 检测表明其具有 6B11ScFv 和 mHSP70 的免疫 活性。 结论 构建表达的 6B11ScFv/mHSP70 融合蛋白具有良好的免疫活性,为进一步研究其体内外抗卵巢癌活性奠定了基础。  相似文献   

8.
根据按蚊偏嗜性密码子对鼠源性恶性疟原虫环子孢子蛋白单链抗体2a10基因进行改造,并融合按蚊抗菌肽cecropin A编码基因。将获得的cecrop-m2a10融合基因克隆入原核表达载体pET32a(+)中,对表达产物进行SDS-PAGE、Western-blot分析并利用琼脂糖扩散法检测其抗菌活性。结果对鼠源性环子孢子蛋白单链抗体2a10中6种氨基酸的170个核苷酸进行了改造,融合cecropinA编码基因,成功构建了cecrop-m2a10融合基因。靶基因在大肠杆菌中以融合蛋白和包涵体的形式高效表达,包涵体经尿素溶解变性及透析复性后表达蛋白的纯度达75%并具备抗大肠杆菌DH5α的活性。本实验为进一步研究cecrop-m2a10在转基因蚊中的多重抗病原效应提供了基础。  相似文献   

9.
重组人源抗HBsAg单链抗体的纯化及亲和常数测定   总被引:7,自引:1,他引:7       下载免费PDF全文
目的:对融合6×His标签的人源抗乙型肝炎表面抗原单链抗体的包涵体进行纯化和复性, 并对复性产物的抗原结合性质进行鉴定。方法:工程菌表达的包涵体裂解后, 金属螯合亲合层析纯化, 然后以尿素透析、盐酸胍透析和金属螯合亲和层析柱原位复性3种方法进行复性;复性产物以免疫亲和层析精制, 非竞争酶免疫法测定亲和常数结果:盐酸胍透析复性产物的比活性最高, 蛋白回收率为(61.08±1.45)%;精制后的重组单链抗体的亲和常数为(2.30±0.32)×107L/mol.结论:本株单链抗体可以应用优化的透析复性技术, 在体外高效复性, 其抗原结合性质不受N末端纯化标签的影响。  相似文献   

10.
人源性抗HBsAg单链抗体在大肠杆菌中的表达及活性测定   总被引:5,自引:0,他引:5  
目的 :制备有活性的人源性抗HBsAg单链抗体。方法 :应用噬菌体表面呈现技术获得人抗乙型肝炎表面抗原(HBsAg)抗体的Fab片段 ,并将VH 和VL 基因以 (Gly4Ser) 3linker连接成单链 ,插入表达载体pQE40 ,筛选大肠杆菌高表达菌株。结果 :工程菌表达优化试验表明 ,在OD6 0 0 为 0 6时开始诱导 ,持续 6h ,目的蛋白表达量最高可达菌体总蛋白的 31%。包涵体变性后上样镍离子螯合层析柱一步纯化 ,收集目的峰 ,透析复性 ,得纯度为 97%的重组单链抗体 ,其亲和常数为 0 2 3× 10 8mol L。结论 :抗HBsAg单链抗体在大肠杆菌内获得高效表达 ,经变性和复性 ,得到有活性的单链抗体 ,氨基酸组成正确。为进行临床前研究打下基础。  相似文献   

11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

16.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

17.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

18.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

19.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

20.
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.  相似文献   

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