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1.
重组人IL-6D24-PE40外毒素融合蛋白的构建及其生物学效应   总被引:1,自引:0,他引:1  
目的 构建重组人白细胞介素6-绿脓杆菌外毒素融合蛋白IL-6D24-PE40,以选择性杀伤高表达IL-6受体(IL-6R)的肿瘤细胞和白血病细胞。方法 采用重叠延伸的基因融合技术将N-末端缺失24个氨基酸的重组人白细胞介素6(IL-6D24)cDNA与缺失细胞结合区的绿脓杆菌外毒素PE40基因进行融合,构建IL-6D24-PE40融合基因。利用HB101/pBV220表达系统,实现了IL-6D24-PE40融合蛋白在大肠杆菌中的高效表达,经MonoQ柱进行层析纯化,采用MTS法检测细胞毒活性。结果 IL-6D24-PE40融合蛋白在大肠杆菌中的表达水平达到40%-60%。包涵体蛋白经分离、复性及纯化得到纯度>95%的融合蛋白。Western blot证明,纯化的融合蛋白与IL-6抗体及PEA抗体均发生特异性结合。细胞毒活性检测证实,IL-6D24-PE40融合蛋白能高度特异地选择性杀伤高表达IL-6R的U937细胞,ID50约为250ng/ml,而对不表达IL-6R的CEM细胞无杀伤作用。结论 IL-6D24-PE40融合蛋白能够选择性杀伤高表达IL-6R的靶细胞,有希望成为导向治疗高表达IL-6/IL-6R系统的某些白血病和其他肿瘤的新型导向药物。  相似文献   

2.
目的 克隆肿瘤抗原MAGE-3基因3’端657bp片段,对其编码的蛋白羧基端97-314aa进行原核表达。方法 从含人MAGE-3基因全长cDNA的pUC19/MAGE-3质粒中经聚合酶链式反应(PCR)扩增3’端657bp片段,并克隆入pGEX-4T-1载体,构建重组原核表达质粒pGEX/MAGE-3,对含有该质粒的大肠杆菌DH5α进行诱导表达。结果 从pUC19/MAGE-3重组质粒中扩增获得一条约660bp的条带,测序结果表明与GenBank公布的MAGE-3序列一致,成功地构建了pGEX/MAGE-3原核表达质粒,含有该质粒的大肠杆菌DH5α经异丙基-β-半乳糖苷(Isopropyl—beta—D—thiogalactopyranoside,IPTG)诱导后表达Mr为54000的谷胱甘肽巯基转移酶(Glutathione S-transferse,GST)融合蛋白。表达的融合蛋白约占菌体蛋白总量的28%。结论 成功地构建了pGEX/MAGE-3原核表达质粒,获得了MAGE-3蛋白羧基端97~314aa融合蛋白,为该蛋白应用于肿瘤免疫治疗奠定了基础。  相似文献   

3.
超抗原SED在大肠杆菌中的表达   总被引:4,自引:2,他引:4  
目的 构建稳定的SED原核表达系统。方法 采用PCR技术扩增葡萄球菌D型肠毒素(SED)超抗原的成熟蛋白编码区DNA序列,构建SED DNA与6个组氨酸基因融合的表达载体pTrcHis-SED,转入E.coli DH5α,IPTG诱导后,用SDS-PAGE和免疫印迹检测融合蛋白的表达情况。目的蛋白用Ni-NTA金属亲和层析法进行纯化,SDS-PAGE和毛细管电泳检测蛋白纯度。结果 成功构建了原核表达载体pTrcHis-SED。分子量约为28000u的6His-SED融合蛋白可在E.coli DH5α中稳定表达。Ni-NTA金属亲和层析后得到纯度较高(>95%)的SED融合蛋白,且具有免疫学活性。结论 本研究为SED免疫识别研究奠定了实验基础。  相似文献   

4.
构建CTLA-4基因表达载体并在大肠杆菌DH5α中表达CTLA-4蛋白。方法:用PCR方法获得中国人CTLA-4基因第二外显子,构建重组表达质粒pPBCTLA,转化大肠杆菌DH5α,以PCR和RFLP方法筛选阳性克隆,以免疫印迹技术检测表达产物。结果:阳性重组子在DH5α中经温度诱导表达CTLA-4蛋白,分子量与理论值相符(约12kD),进一步分析表明,CTLA-4蛋白主要以包涵体形式存在。Western-blot结果证实,12k的表达条带可与标准羊抗人CTLA-4ITgG起特异反应。淋巴细胞转化实验结果表明该蛋白具有明显的免疫抑制作用。结论:用基因工程技术获得中国人CTLA-4基因表达蛋白,为进一步研究CTLA-4的生物学功能及研制CTLA-4抗体奠定了基础。  相似文献   

5.
建立了人FL(human flt3 ligand,hFL)在大肠杆菌中的高效表达系统,分离纯化重组hFL为其功能和应用研究打下基础。根据大肠杆菌偏爱密码子人工合成hFL基因膜外DNA片段,由PCR方法获得的hFL基因膜外区DNA片段,经测序证明序列正确。构建表达载体pET30a-Trx-hFL并转化大肠杆菌BL21(DE3),IPTG诱导表达,hFL融合蛋白的表达占菌体总蛋白的60%以上,并以包涵体形式存在。融合蛋白经离子交换层析、分子筛层析纯化,并用FXa切割,切割效率>80%。切割产物经亲和层析纯化。纯化产物进行Western blot鉴定。纯化的rhFL(recombinant hFL)与GM-CSF及TNFα联合作用,具有良好的刺激DC增殖活性,其增殖能力是GM-CSF+TNFα的2.5倍左右。本文以大肠杆菌为宿主,成功地表达了融合蛋白Trx-hFL。经纯化的rhFL在体外与GM-CSF及TNFα联合使用能有效地刺激人DC的增殖。  相似文献   

6.
目的:在大肠杆菌中表达野生型和突变型重组人IL13,经纯化复性获得具有有活性的蛋白。方法:用PCR扩增IL13基因片段,用定点突变PCR获得其突变体(IL13’)基因。将IL13和IL13’基因分别克隆至原核表达载体pET30a( )中,构建重组体pET30a( )IL13和pET30a( )IL13’,分别命名为pETIL13和pETIL13’。以重组体转化E.coliBL21(DE3)在IPTG诱导下进行表达。表达产物用NiNTA层析柱进行纯化。纯化产物用氧化还原谷胱甘肽系统透析复性后,检测其生物学活性。结果:在E.coliBL21(DE3)中表达了IL13/IL13’His6融合蛋白。经SDSPAGE显示,融合蛋白的Mr约17000,经Westernblot证实为人IL13。表达的融合蛋白以包涵体的形式存在,纯化后得到较高纯度的重组蛋白。复性后的包涵体检测具有生物学活性。结论:成功地获得具有生物学活性的野生型和突变型人IL13重组蛋白,为下一步研究奠定了基础。  相似文献   

7.
目的 克隆人单纯疱疹病毒I、Ⅱ(HSV-I、Ⅱ)型共同性抗原gD基因,构建重组表达载体pMAL-c2/gD,诱导融合蛋白MBP-gD的表达。方法 提取病毒DNA,PCR扩增出gD基因,克隆于原核表达载体pMAL-c2并转化大肠埃希菌DH5α。PCR、双酶切及测序证实插入的gD基因序列正确后,IPTG诱导表达融合蛋白MBP-gD,并进行免疫学鉴定。结果 构建的重组表达质粒pMAL-c2/gD在大肠埃希菌中能高效表达。经SDS-PAGE分析,表达产物约占菌体总蛋白35.5%,其中39%以可溶蛋白形式存在于胞质中,61%以包涵体形式存在。结论 构建了pMAL-c^2/gD表达质粒,Western blot证实,HSV-I gD单克隆抗体DL6可特异识别表达的gD蛋白,该蛋白具有天然gD的抗原性。  相似文献   

8.
目的 构建结核杆菌HSP70与肿瘤抗原MAGE-1的融合基因,在大肠杆菌中进行表达,并通过GST纯化系统进行分离纯化。方法 利用PCR方法扩增TBHSP70基因,经测序后连入原核表达载体pGEX-4T-1,再通过PCR方法扩增MAGE-1基因片段(289~927bp),测序后插入TBHSP70基因的5’端,构建MAGE-1与TBHSP70的N端融合基因原核表达质粒pGEX-MAGE-1-TBHSP70,含有该质粒的大肠杆菌DH5a进行诱导表达和分离纯化。结果 成功地扩增了TBHSP70基因与MAGE-1基因片段,测序结果表明与GenBank公布的序列一致;成功地构建了pGEX-MAGE-1-TBHSP70原核表达质粒,含有该质粒的大肠杆菌DH5α经IPTG诱导后表达一Mt约为125000的蛋白,经GST融合蛋白表达系统纯化,得到了MAGE-1与TBHSP70的融合蛋白。结论 成功地获得了MAGE-1与TBHSP70的融合蛋白,为研究MAGE-1-TBHSP70融合蛋白在肿瘤免疫治疗中的作用奠定了基础。  相似文献   

9.
目的构建人络氨酸激酶6(PTK6)与His融合蛋白重组表达载体,在大肠杆菌中诱导表达,并对重组蛋白进行纯化。方法通过PCR在编码PTK6的cDNA序列两端添加EcoR I和BamH I酶切位点,双酶切后将编码PTK6的cDNA序列亚克隆至原核表达载体PHUE构建重组蛋白表达载体PHUE/PTK。重组载体经鉴定后转化大肠杆菌表达菌株BL21(DE3)感受态细胞。IPTG诱导重组蛋白表达。收集菌体裂解后,用尿素洗涤和溶解包涵体。溶解上清经Ni-NTA亲和层析柱纯化,并用SDS-PAGE和Western blotting检测纯化产物。结果成功构建人PTK6重组蛋白原核表达载体,重组蛋白以包涵体形式表达,其相对分子质量为55 000,与预期一致。亲和层析纯化产物的SDS-PAGE和Western blotting鉴定表明获得纯度大于80%的目的重组蛋白。结论人PTK6 His融合蛋白的纯化为多克隆及单克隆抗体的制备以及结构和功能的研究奠定了基础。  相似文献   

10.
目的:构建表达幽门螺杆菌(Hp)细胞毒素相关蛋白(CagA)及粘膜免疫佐剂量霍乱毒素B亚单位(CTB)的重组质粒,并在大肠杆菌中表达获得基因重组蛋白。方法:用PCR方法从幽门螺杆菌扩增CagA基因片段,从霍乱弧菌扩增CTB基因片段,将它们转入原核载体质粒pGEMEX-1,在大肠杆菌DH5α中克隆,并在JM109DE3中表达。结果:重组质粒pEGEMEX-CTB的全长序列经分析与GenBank公布的序列相符;各表达蛋白经SDS-PAGE分析,相对分子量与文献相符;重组蛋白经Westem blot检测有较强的抗原性。结论:基因重组菌表达的融合蛋白有可能作为有效抗原用于幽门螺杆菌疫苗的研制及检测试剂盒的制备。  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.
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   

18.
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   

19.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

20.
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   

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