首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 171 毫秒
1.
本研究比较了德国产阿克苏(AKZONOBLE)和国产科华抗HCVELISA诊断试剂盒用于献血员筛选的敏感性。使用AKZO试剂盒于青岛市中心血站1242例职业献血员中筛查出44份阳性血清,再将该44份阳性血清用国产科华试剂盒检测,结果仅有18份呈阳性反应,其它26份均呈阴性反应;13份经AKZO检测为阴性的血清,科华试剂盒检测全部呈阴性反应。统计学处理两试剂盒敏感性具有极显著差异(P<0.01)。表明国产科华试剂盒敏感性低于AKZO试剂盒,有待于进一步改进和完善。  相似文献   

2.
采用固相法合成HIV-1和HIV-2两个多肽,建立了用混合多肽为包被抗原检测HIV-1和HIV-2感染的间接酶联免疫吸附法。检测46份抗HIV-1和HIV-2抗体阳性血清标本以及94份对照血清标本,与UBI试剂比较,其阳性符合率为97.8%,阴性符合率为100%,总符合率为99.3%。实验结果表明,此法可用于HIV-1和HIV-2感染的检测。  相似文献   

3.
戊肝与丙肝病毒在献血员人群中感染状况的对比研究   总被引:1,自引:0,他引:1  
采用市售试剂对武汉地区乡村献血员进行血清抗HEV与抗HCV检测,两者的阳性率分别为5.74%及9.35%。在288份有ALT记录的单采浆献血员中,有近期ALT升高史的献浆者抗HEV及抗HCV检出率分别为14.04%及14.18%,均显著高于无近期ALT升高史的献浆者。对上述标本同时进行多项血清HBV标志检测,抗HEV阳性及抗HCV阳性组献血员多项HBV标志检测结果与相应阴性组比较均未见显著的差别。  相似文献   

4.
HIV—1 SF2株env基因(120)在大肠杆菌中的表达   总被引:3,自引:0,他引:3  
王斌  邵一鸣 《病毒学报》1996,12(1):18-22
运用基因重组技术,将HIV-1 SF2株编码外膜蛋白gp120的env基因片段与原核载体pBV220进行重组,构建成质粒pBVSF2env,并在大肠杆菌(E.CoilDH10b)中获得表达,经Westemblot反应证实,该重组蛋白与来自HIV-1感染者的血清(含多克隆抗体)发生特异性反应。  相似文献   

5.
余传霖 《微生物与感染》1997,20(2):14-16,30
本文介绍了人类免疫缺陷病毒1型(HIV-1)感染中有关中和抗体研究的新近进展,包括中和抗体反应的特异性,如中和表位的种类和表达,HIV中和反应的机制等。地HIV-1gp120和gp41分子的研究结果资料,作了较为详尽的描述。文中尚提出了HIV感染预防疫苗研制的途径。  相似文献   

6.
用戊肝病毒(HEV)基因组编码氨基酸序列1-901-914/2-515-530、3-91-123、2-613-654相应的三段合成多肽为抗原、研制出一种检测抗-HEVIgG的ELISA试剂。以该试剂检测中国、缅甸、印度和前苏联肠道传播非乙型肝炎(ET-NANBH)病人血清105份,仅3份中国病人血清阴性,阳性率为97.1%;检查实验感染HEVL赤猩猩血清,感染前阴性,感染后阳性;检查正常人血清99  相似文献   

7.
单纯疱疹病毒(HSV)Ⅰ型及Ⅱ型之间有很多共同抗原,能引起血清学交叉反应,鉴别诊断比较困难。本实验利用重组DNA技术,将部分HSV-2DNA的PstI片段克隆到载体质粒PSK中,并筛选出两个重组质粒(P和P)只与HSV-2反应,与HSV-1不反应,这两个重组质粒中所含的HSV-2DNA片段大小分别是3.1和4.3kb,另外,还筛选了一个重组质粒(PHSV2-1,含5.8kbHSV-2DNA片段)与HSV-1和HSV-2均反应。将4.3kb的片段用光生物素标记后作为探针检测了159份人阴道拭子,其中23份样品呈阳性反应,其余均为阴性,从23份阳性样品中挑选12价涂片用间接荧光抗体法检测也都呈阳性反应,随机挑选的几份杂交反应阴性样品在间接荧光试验中也是阴性。本实验制备的HSV通用及HSV-2型特异性探针将比常规的血清学方法诊断和鉴别HSV-1和HSV-2感染更为可靠。  相似文献   

8.
人源单克隆抗人免疫缺陷病毒1型抗体Fab段基因的获得   总被引:1,自引:0,他引:1  
应用噬苏体抗体库技术有效地筛选出了多株抗HIV-1人源单克隆抗体。以逆转录聚合酶链反应(RT-PCR)从HIV-1感染者外周血淋巴细胞中扩增抗体轻重链可变区基因,插入载体pCOMB3,建立噬菌体抗体库。分别以HIV-1gp120和gp160为固相抗原,经过多轮筛选,从中获得了多株抗HIV-1gp41、gp120和gp160的单克隆抗体Fab段基因。抗HIV特异性噬菌体抗体随抗体库的筛选高度富集,抗  相似文献   

9.
HRP-HBVDNA探针在临检应用中的研究   总被引:2,自引:0,他引:2  
本文介绍了一种简便的检测血清HBVDNA的方法。参照Renz等人的标记方法,构建了直接酶标HRP HBVDNA探针。此探针经与固定在硝酸纤维素滤膜上的血清靶DNA杂交后,可通过化学发光自显影检测技术观察结果。敏感度可检测0-1pg靶DNA,相当于同位素探针的灵敏度。对63份HBsAgHBeAg和Anti HBcELISA阳性血清以及24份HBsAgAnti HBc阳性,HbeAg阴性血清用HRP HBVDNA探针进行检测,结果探针HBVDNA阳性率分别为100%(63)和58%(14);对50份HBsAg,ELISA阴性和ALT正常的血清,探针HBVDNA全部阴性。实验结果表明本方法具有很大的推广应用价值。  相似文献   

10.
为了确定从噬菌体抗体文库中筛选出的抗体的属性和方便目的基因的表达及其产物的纯化,对两株具有“1F7”独特型的抗HIV-1gp160抗体基因进行了序列分析并构建了可溶性表达载体.发现3B株含有完整的Fab段,1D株只有重链Fd段.序列测定表明两株克隆的Fd段基因完全相同,其可变区VH属于VHⅠ亚群,而3B株的“轻链”序列与已知的人的κ和λ轻链无同源性.用从另外的Fab抗体文库中筛选出来的3株抗乙肝表面抗原抗体的轻链与3B的重链重组,并选择一个HIV-1gp160特异性较好的重组抗体株,命名为3Bs.构建了1D株与3Bs株的可溶性表达载体,免疫印迹实验证实了具有“1F7”独特型的抗gp160独特型阳性抗体的表达.  相似文献   

11.
The reactivity of antibodies with dimeric and monomelic peptide antigens was compared by ELISA. A panel of highly purified synthetic peptides of HIV-1 representing defined regions, 598–609 and 524 533 (fusion domain) of gp41 and 306–320 of gpl20, were used as antigens in the ELISA. These peptides were selected and synthesized taking into account the level of sequence conservation of various strains and hydrophilicity. The analysis included sera from 52 HIV-1 infected individuals and 53 HIV-1 negative controls. Both peptides from gp41 were found to be particularly immunoreactive with sera from HIV-1 infected individuals. The frequency of reactivity to the selected peptide from gp120 (V3 loop) in infected individuals was 82%. An interesting observation was that the dimeric peptide antigens had a detection rate more than 4-fold higher than the monomeric antigens. We found that lower levels of antibodies could be detected with dimeric antigens. The peptides reacted with few sera other than HIV-1 positive sera. These results implicate the potential dimeric peptide antigens to be utilized in the serodiagnosis of HIV-1 infection.  相似文献   

12.
The aim of this study was to evaluate the performance of commercially available anti-HIV assays when testing plasma, urine and oral mucosal transudate (OMT) samples for the presence of antibodies to HIV. Homologous sets of plasma, urine and oral mucosal transudate specimens were collected from 288 hospitalized patients in northern Tanzania and tested for antibodies to HIV using a routine enzyme immunoassay (Recombinant 3rd Generation EIA, Abbott) and two rapid assays (Testpack HIV-1/HIV-2; Abbott and SUDS HIV-1, Murex). Incubation times and/or sample volumes when testing OMT or urine were increased as compared to those recommended for plasma. The corresponding plasma specimens from all repeatedly reactive samples and samples presenting discordant results were subjected to confirmational testing by an HIV-1/2 Western blot. A total of 15.3% (44/288) of the plasma samples were anti-HIV-1 positive by Western blot. The sensitivity using plasma was 100% by all assays, 69.7-97.7% using urine, and 92.7-100% using oral transudate specimens. The sensitivity of both rapid assays was excellent and higher than the EIA when testing OMT. Specificities ranged from 98.8-100% for plasma, 99-100% for urine and were 100% by all assays using oral samples. The results obtained using oral mucosal transudate specimens and rapid assays were at least comparable to those obtained with plasma, while the use of urine specimens produced suboptimal sensitivities with two of the three assays. The testing of alternative body fluids for antibodies to HIV is yet another strategy that may be applicable, particularly in developing countries.  相似文献   

13.
An 80-kilodalton glycoprotein (gp80) was produced in human immunodeficiency virus type 2 (HIV-2)-infected cells along with three envelope glycoproteins that we have recently reported: the extracellular glycoprotein (gp125), the envelope glycoprotein precursor (gp140), and the transient dimeric form of the precursor (gp300). gp125 and gp80 were detectable after the synthesis of gp140 and the formation of gp300. Using a specific monoclonal antibody, we showed here that gp80 is a dimeric form of the transmembrane glycoprotein gp36 of HIV-2. Dimerization of the envelope glycoprotein precursor and dimeric forms of the transmembrane glycoproteins were also observed in cells infected with simian immunodeficiency virus (SIV-mac), a virus closely related to HIV-2. Under routine conditions of our experiments (i.e., extraction by 1% Triton X-100 before polyacrylamide gel electrophoresis in sodium dodecyl sulfate [SDS]), monomeric forms of the transmembrane glycoprotein of HIV-2 and SIV-mac were only seldomly observed. Dimeric forms of the envelope precursors and the transmembrane glycoproteins are probably stabilized by extraction in the nonionic detergent Triton X-100 since such dimeric forms resist dissociation during subsequent electrophoresis in the presence of the ionic detergent SDS. However, the dissociation of these dimeric forms might occur when samples are prepared by extraction directly in 1% SDS or by incubation of the purified dimers at acidic pH. Dimerization of the envelope precursor might be required for its processing to give the mature envelope proteins, whereas the transmembrane dimer might be essential for optimal structure of the virion and thus its infectivity.  相似文献   

14.
The antigenicity of three chimeric synthetic peptides (Qm, Qm-16, and Qm-17) incorporating an immunodominant epitope of the gp41 transmembrane protein (587-617) and the different epitopes of the gp120 envelope protein (495-516), (301-335), (502-516) of human immunodeficiency virus (HIV-1), separated by two glycine residues, was evaluated by UltramicroEnzyme-linked immunosorbent assay (UMELISA) by using panels of anti-HIV-1 positive sera (n = 47). The specificity was evaluated with samples from healthy blood donors (n = 20) and anti-HIV-2 positive samples (n = 10). The results indicate that the chimeric peptide, Qm, was the most reactive one because it detected antibodies to virus efficiently. This may be related to peptide adsorption onto the solid surface, the C-terminal region of HIV-1 gp120 (495-516) combined with gp41 (587-617) in the chimera, and the epitope accessibility to the antibodies. This study showed the usefulness of the chimeric peptides as antigen to detect antibodies to HIV-1 virus.  相似文献   

15.
We have investigated the induction of protective mucosal immunity to human immunodeficiency virus type 1 (HIV-1) isolate 89.6 by intranasal (i.n.) immunization of mice with gp120 and gp140 together with interleukin-12 (IL-12) and cholera toxin subunit B (CTB) as adjuvants. It was found that both IL-12 and CTB were required to elicit mucosal antibody responses and that i.n. immunization resulted in increased total, immunoglobulin G1 (IgG1), and IgG2a anti-HIV-1 antibody levels in serum; increased total, IgG1, IgG2a, and IgA antibody expression in bronchoalveolar lavage fluids; and increased IgA antibody levels in vaginal washes. Levels of anti-HIV-1 antibodies in both sera and secretions were higher in groups immunized with gp140 than in those immunized with gp120. However, only gp120-specific mucosal antibodies demonstrated neutralizing activity against HIV-1 89.6. Taken together, the results show that IL-12 and CTB act synergistically to enhance both systemic and local mucosal antibody responses to HIV-1 glycoproteins and that even though gp140 induces higher antibody titers than gp120, only gp120-specific mucosal antibodies interfere with virus infectivity.  相似文献   

16.
We have used an indirect-capture enzyme-linked immunosorbent assay to quantitate the reactivity of sera from human immunodeficiency virus type 1 (HIV-1)-infected humans with native recombinant gp120 (HIV-1 IIIB or SF-2) or with the gp120 molecule (IIIB or SF-2) denatured by being boiled in the presence of dithiothreitol with or without sodium dodecyl sulfate. Denaturation of IIIB gp120 reduced the titers of sera from randomly selected donors by at least 100-fold, suggesting that the majority of cross-reactive anti-gp120 antibodies present are directed against discontinuous or otherwise conformationally sensitive epitopes. When SF-2 gp120 was used, four of eight serum samples reacted significantly with the denatured protein, albeit with ca. 3- to 50-fold reductions in titer. Only those sera reacting with denatured SF-2 gp120 bound significantly to solid-phase-adsorbed SF-2 V3 loop peptide, and none bound to IIIB V3 loop peptide. Almost all antibody binding to reduced SF-2 gp120 was blocked by preincubation with the SF-2 V3 loop peptide, as was about 50% of the binding to native SF-2 gp120. When sera from a laboratory worker or a chimpanzee infected with IIIB were tested, the pattern of reactivity was reversed, i.e., there was significant binding to reduced IIIB gp120, but not to reduced SF-2 gp120. Binding of these sera to reduced IIIB gp120 was 1 to 10% that to native IIIB gp120 and was substantially decreased by preincubation with IIIB (but not SF-2) V3 loop peptide. To analyze which discontinuous or conformational epitopes were predominant in HIV-1-positive sera, we prebound monoclonal antibodies (MAbs) to IIIB gp120 and then added alkaline phosphatase-labelled HIV-1-positive sera. MAbs (such as 15e) that recognize discontinuous epitopes and compete directly with CD4 reduced HIV-1-positive sera binding by about 50%, whereas neutralizing MAbs to the C4, V2, and V3 domains of gp120 were either not inhibitory or only weakly so. Thus, antibodies to the discontinuous CD4-binding site on gp120 are prevalent in HIV-1-positive sera, antibodies to linear epitopes are less common, most of the antibodies to linear epitopes are directed against the V3 region, and most cross-reactive antibodies are directed against discontinuous epitopes, including regions involved in CD4 binding.  相似文献   

17.
b12, one of the few broadly neutralizing antibodies against HIV-1, binds to the CD4 binding site (CD4bs) on the gp120 subunit of HIV-1 Env. Two small fragments of HIV-1 gp120, b121a and b122a, which display about 70% of the b12 epitope and include solubility-enhancing mutations, were designed. Bacterially expressed b121a/b122a were partially folded and could bind b12 but not the CD4bs-directed non-neutralizing antibody b6. Sera from rabbits primed with b121a or b122a protein fragments and boosted with full-length gp120 showed broad neutralizing activity in a TZM-bl assay against a 16-virus panel that included nine Tier 2 and 3 viruses as well as in a five-virus panel previously designed to screen for broad neutralization. Using a mean IC50 cut-off of 50, sera from control rabbits immunized with gp120 alone neutralized only one virus of the 14 non-Tier 1 viruses tested (7%), whereas sera from b121a- and b122a-immunized rabbits neutralized seven (50%) and twelve (86%) viruses, respectively. Serum depletion studies confirmed that neutralization was gp120-directed and that sera from animals immunized with gp120 contained lower amounts of CD4bs-directed antibodies than corresponding sera from animals immunized with b121a/b122a. Competition binding assays with b12 also showed that b121a/2a sera contained significantly higher amounts of antibodies directed toward the CD4 binding site than the gp120 sera. The data demonstrate that it is possible to elicit broadly neutralizing sera against HIV-1 in small animals.  相似文献   

18.
To date, only a small number of anti-human immunodeficiency virus type 1 (HIV-1) monoclonal antibodies (MAbs) with relatively broad neutralizing activity have been isolated from infected individuals. Adequate techniques for defining how frequently antibodies of these specificities arise in HIV-infected people have been lacking, although it is generally assumed that such antibodies are rare. In order to create an epitope-specific neutralization assay, we introduced well-characterized HIV-1 epitopes into the heterologous context of simian immunodeficiency virus (SIV). Specifically, epitope recognition sequences for the 2F5, 4E10, and 447-52D anti-HIV-1 neutralizing monoclonal antibodies were introduced into the corresponding regions of SIVmac239 by site-directed mutagenesis. Variants with 2F5 or 4E10 recognition sequences in gp41 retained replication competence and were used for neutralization assays. The parental SIVmac239 and the neutralization-sensitive SIVmac316 were not neutralized by the 2F5 and 4E10 MAbs, nor were they neutralized significantly by any of the 96 HIV-1-positive human plasma samples that were tested. The SIV239-2F5 and SIV239-4E10 variants were specifically neutralized by the 2F5 and 4E10 MAbs, respectively, at concentrations within the range of what has been reported previously for HIV-1 primary isolates (J. M. Binley et al., J. Virol. 78:13232-13252, 2004). The SIV239-2F5 and SIV239-4E10 epitope-engrafted variants were used as biological screens for the presence of neutralizing activity of these specificities. None of the 92 HIV-1-positive human plasma samples that were tested exhibited significant neutralization of SIV239-2F5. One plasma sample exhibited >90% neutralization of SIV239-4E10, but this activity was not competed by a 4E10 target peptide and was not present in concentrated immunoglobulin G (IgG) or IgA fractions. We thus confirm by direct analysis that neutralizing activities of the 2F5 and 4E10 specificities are either rare among HIV-1-positive individuals or, if present, represent only a very small fraction of the total neutralizing activity in any given plasma sample. We further conclude that the structures of gp41 from SIVmac239 and HIV-1 are sufficiently similar such that epitopes engrafted into SIVmac239 can be readily recognized by the cognate anti-HIV-1 monoclonal antibodies.  相似文献   

19.
Human immunodeficiency virus-type I (HIV-1) infection elicits antibodies (Abs) directed against several regions of the gp120 and gp41 envelope glycoproteins. Many of these Abs are able to neutralize T-cell-line-adapted strains (TCLA) of HIV-1, but only a few effectively neutralize primary HIV-1 isolates. The nature of HIV-1 neutralization has been carefully studied using human monoclonal Abs (MAbs), and the ability of such MAbs to act in synergy to neutralize HIV-1 has also been extensively studied. However, most synergy studies have been conducted using TCLA strains. To determine the nature of Ab interaction in HIV-1 primary isolate neutralization, a panel of 12 anti-HIV-1 human immunoglobulin G (IgG) MAbs, specific for epitopes in gp120 and gp41, were used. Initial tests showed that six of these MAbs, as well as sCD4, used individually, were able to neutralize the dualtropic primary isolate HIV-1(89.6); MAbs giving significant neutralization at 2 to 10 microg/ml included 2F5 (anti-gp41), 50-69 (anti-gp41), IgG1b12 (anti-gp120(CD4bd)), 447-52D (anti-gp120(V3)), 2G12 (anti-gp120), and 670-D (anti-gp120(C5)). For studies of reagent interaction, 16 binary combinations of reagents were tested for their ability to neutralize HIV-1(89.6). Reagent combinations tested included one neutralizing MAb with sCD4, six pairs consisting of two neutralizing MAbs, and nine pairs consisting of one neutralizing MAb with another non-neutralizing MAb. To assess the interaction of the latter type of combination, a new mathematical treatment of reagent interaction was developed since previously used methods could be used only when both reagents neutralize. Synergy was noted between sCD4 and a neutralizing anti-gp120(V3) MAb. Antagonism was noted between two pairs of anti-gp41 MAbs (one neutralizing and one non-neutralizing). All of the other 13 pairs of MAbs tested displayed only additive effects. These studies suggest that Abs rarely act in synergy to neutralize primary isolate HIV-1(89.6); many anti-HIV-1 Abs act additively to mediate this biological function.  相似文献   

20.
Human Immunodeficiency Virus (HIV-1) poses a serious threat to the developing world and sexual transmission continues to be the major source of new infections. Therefore, the development of molecules, which prevent new HIV-1 infections, is highly warranted. In the present study, a panel of human hemoglobin (Hb)-α subunit derived peptides and their analogues, with an ability to bind gp120, were designed in-silico and their anti-HIV-1 activity was evaluated. Of these peptides, HbAHP-25, an analogue of Hb-α derived peptide, demonstrated significant anti-HIV-1 activity. HbAHP-25 was found to be active against CCR5-tropic HIV-1 strains (ADA5 and BaL) and CXCR4-tropic HIV-1 strains (IIIB and NL4-3). Surface plasmon resonance (SPR) and ELISA revealed direct interaction between HbAHP-25 and HIV-1 envelope protein, gp120. The peptide prevented binding of CD4 to gp120 and blocked subsequent steps leading to entry and/or fusion or both. Anti-HIV activity of HbAHP-25 appeared to be specific as it failed to inhibit the entry of HIV-1 pseudotyped virus (HIV-1 VSV). Further, HbAHP-25 was found to be non-cytotoxic to TZM-bl cells, VK2/E6E7 cells, CEM-GFP cells and PBMCs, even at higher concentrations. Moreover, HbAHP-25 retained its anti-HIV activity in presence of seminal plasma and vaginal fluid. In brief, the study identified HbAHP-25, a novel anti-HIV peptide, which directly interacts with gp120 and thus has a potential to inhibit early stages of HIV-1 infection.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号