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1.
丙型肝炎病毒NS5ab区的B细胞模拟表位的确认   总被引:1,自引:1,他引:1  
侯利华  杜桂鑫  王海涛 《免疫学杂志》2003,19(4):265-268,273
目的:用噬菌体展示随机肽库研究丙型肝炎病毒(HCV)NS5ab区的B细胞表位。方法:在原核系统中表达了HCV NS5ab重组蛋白,亲和层析纯化血清中抗HCV NS5ab的特异多抗,用此多抗来筛选噬菌体递呈随机12肽库,获得HCV NS5ab区的B细胞表位。结果:成功地表达了HCV NS5ab重组蛋白,用此蛋白检验了130份HCV阳性血清,阳性率为36%。在筛选的噬菌体展示随机肽库后,挑取13个阳性克隆测序,有9个序列不同,最终通过噬菌体表位表达的方法确认了3个表位。结论:筛选噬菌体展示随机肽库研究HCV的B细胞模拟表位是可行的。  相似文献   

2.
丙型肝炎病毒非结构蛋白NS4A抗原模拟表位的筛选和鉴定   总被引:10,自引:3,他引:10  
目的:筛选丙型肝炎病毒(hepatitis C virus,HCV)非结构蛋白NS4A(HCV NS4A)特异性噬菌体模拟表位,为抗HCV的疫苗研究探索新途径。方法:以抗HCV NS4A的单克隆抗体作为固相筛选分子,对人工合成的噬菌体随机12肽库进行5轮“吸附-洗脱-扩增”的筛选过程,随机挑取45个克隆,经噬菌体酶联免疫吸附法(ELISA)鉴定并进行交叉反应实验以及竞争抑制性结合实验,最后对所选克隆进行DNA序列分析,以确定HCV NS4A抗原的模拟表位。结果:经噬菌体富集后,从随机筛选的45个克隆中得到13个阳性克隆,确定氨基酸序列XXRXXMXPXXXI为HCV NS4A的模拟表位。结论:用噬菌体12肽库成功筛选得到HCV NS4A的模拟表位,为开展用HCV模拟表位探索HCV的防治研究创造了条件。  相似文献   

3.
目的:筛选和鉴定乙酰胆碱酯酶的有效抗原表位。方法:收集乙酰胆碱受体抗体阴性而乙酰胆碱酯酶抗体阳性的重症肌无力病人血清,采用溴化氰活化的琼脂糖柱(CNBr-actived sepharose^TM4B)纯化抗乙酰胆碱酯酶的多克隆抗体并定量;用纯化的抗乙酰胆碱酯酶的抗体对随机的12肽噬菌体表面显示肽库进行5轮免疫学筛选,随机挑取克隆;采用Western blot免疫识别,识别为阳性的克隆进行核苷酸序列的测定,并与乙酰胆碱酯酶的氨基酸序列进行同源性比较。将获得的不同表位的阳性克隆分别免疫小鼠,采用Western blot筛选能刺激小鼠产生抗乙酰胆碱酯酶抗体的阳性克隆,进行生物学活性的鉴定。结果:经5轮免疫学筛选后挑取的49个克隆中,经Westem blot识别15个克隆能被抗乙酰胆碱酯酶抗体识别。核苷酸序列分析发现共有7种不同的表位,其中1种表位与乙酰胆碱酯酶有较高的同源性,其余6种表位与其无一级结构的同源性。经动物免疫初步实验筛选,共有5个免疫原性较强的阳性克隆,其免疫的鼠血清均可识别人乙酰胆碱酯酶。结论:获得了5种乙酰胆碱酯酶的有效抗原表位,1种可能为结构表位,4种为模拟表位。  相似文献   

4.
目的:观察变应原卵清蛋白核心表位类似物对昆明鼠哮喘模型的实验性治疗作用。方法:用抗OVA多克隆抗体筛选噬菌体随机十五肽库,根据其结果反推出氨基酸序列,合成了一个针对于保守序列的8肽,将其用于小鼠哮喘模型的实验性治疗。结果:该小肽对小鼠哮喘模型的症状有明显的改善作用。结论:可用多抗筛选肽库并得到具有改善症状活性的核心表位类似物。  相似文献   

5.
目的;观察就奕原卵清蛋白核心表位类似物对昆明鼠哮喘模型的实验性治疗作用。方法:用抗OVA多克隆抗体筛选噬菌体随机十五肽库,根据其结果反推出氨基酸序列,合成了一个针对于保守序列的8肽,将其用于小鼠哮喘模型的实验性治疗。结果:该小肽对小鼠哮喘模型的症状有明显的改善作用。结论;可用抗筛选肽库并得到具有改善症状活性的核心表位类似物。  相似文献   

6.
目的:制备多克隆抗体并初步用于TRP—1抗原表位区的研究,为白癜风、恶性黑素瘤的免疫治疗提供实验依据。方法:在大肠杆菌中表达PRSETA/TRP—1融合蚩白,用所获得的蛋白免疫新西兰白兔得到多克隆抗体,并用ELISA、Western—blot方法进行此抗体的鉴定。结果:①表达了PRSETA/TRP—1融合蛋白;②制备了抗TRP—1B细胞表位区的多克隆抗体;③并用多克隆抗体检测了毕赤酵母表达的6His—TRP1蛋白,证实此抗体效价高、特异性强。结论:此抗体可用于TRP—1B细胞表位肽段的进一步研究。  相似文献   

7.
以特异性噬菌体展示肽为靶筛选TNF-α结合肽的研究   总被引:3,自引:0,他引:3  
目的:建立以特异性噬菌体展示肽为靶从噬菌体肽库中筛选结合表位的新方法。方法:以前期工作中筛选得到的模拟TNF-α表位的环七肽克隆LCS-7(c-RRPAQSG-c)为靶,筛选噬菌体线性十二肽库;用间接ELISA及竞争试验鉴定阳性克隆。结果:对噬菌体十二肽库进行3轮筛选后,挑取20个克隆中有10个为阳性克隆,测序结果氨基酸序列相同:EHMALTYPFRPP。结论:以TNF-α模拟肽克隆为靶筛选得到的噬菌体十二肽克隆,能够与TNF-α结合,为TNF-α结合肽;所测得序列完全一致。上述结果提示了该筛选方法的可行性。  相似文献   

8.
从噬菌体环肽库中筛选TNF-α表位模拟肽的研究   总被引:1,自引:1,他引:1  
目的:用具有中和活性的抗TNF—α单抗(mAb)J1D9筛选噬菌体环七肽库,从中获得可模拟TNF—α表位的短肽。方法:筛选TNF—α表位模拟肽,并用夹心ELISA法鉴定阳性克隆。结果:对环七肽库进行3轮筛选后,随机挑选20个噬菌体克隆,经ELISA鉴定出9个阳性克隆。DNA序列分析后,推导的氨基酸序列共3种:c—RRPAQSG—c、c—NKHNRKI—c和c—RGMSRKI—c。结论:筛选的环七肽克隆展示肽具有TNF—α的抗原性,为TNF—α表位模拟肽。  相似文献   

9.
目的 用噬菌体展示肽库技术筛选甲型肝炎(甲肝)病毒抗原模拟表位,为病毒抗原决定簇定位探索可行方法.方法 用纯化的抗甲肝病毒单克隆抗体,对噬菌体展示12肽库进行3轮“吸附-洗脱-扩增”筛选,随机挑取10个克隆,用酶联免疫吸附法(ELISA)对噬菌体克隆进行抗原性鉴定、竞争抑制鉴定及DNA序列测定分析,推导出展示肽氨基酸序列并与甲肝病毒(HAV)代表株结构蛋白氨基酸序列比较.结果 10个噬菌体克隆ELISA检测全为阳性,9个具有一致序列,与HAVHM175株结构蛋白中和活性表位之一:VP1 157-171区具有类似序列,另一株噬菌体克隆在HAVHM175中未发现类似序列,结果表明这些展示肽可能是HAV抗原模拟表位.结论 用噬菌体展示肽库技术筛选得到了HAV模拟表位,为开展病毒模拟表位研究打下了基础.  相似文献   

10.
从随机9肽库中筛选HCV抗原表位   总被引:1,自引:0,他引:1  
目的 :用患者血清中抗HCV抗体从随机 9肽库中筛选HCV抗原表位。方法 :将病人血清用硫酸铵粗提后 ,用ProteinA亲和层析柱纯化和制备抗HCV多克隆抗体 ;以此为筛选配基 ,对噬菌体表面展示的随机 9肽库进行亲和筛选。结果 :三轮筛选的投入产出比逐轮升高至 5 0× 10 - 3 、假阳性率逐轮降低至 0 2 % ,提示具有良好的富集效果。从第三轮挑选出的 15个克隆进行结合试验 ,发现 7个克隆只与HCV抗体有较强的结合力而不与正常人血清反应 ;测序表明 6个克隆的外源肽含有核心序列SPVAXVLXT。用阳性噬菌体克隆检测 2 0例病人血清 ,有程度不等的阳性反应。结论 :用多克隆抗体从噬菌体随机肽库中筛选得到了有一定功能的模拟表位。  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.
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   

13.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  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.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

19.
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   

20.
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   

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