HBc-HLA-A*1101-β2m复合物单体及其四聚体的制备和鉴定

目的制备HBc-HLA-A ＊ 1101-β2m复合物单体和四聚体,并对其特异性进行了鉴定。方法原核高效表达的HLA-A ＊ 1101-BSP和β2m蛋白,在抗原肽（乙型肝炎病毒的核心蛋白HBc88-96）的存在下,体外复性折叠成可溶性的HLA-A ＊ 1101抗原肽复合物单体,经BirA酶作用并通过凝胶过滤层析法纯化复合物单体;然后将此复合物单体与藻红蛋白标记的链霉亲和素按一定比例耦合构建成四聚体;最后用流式细胞仪检测分析该四聚体结合特异性CTL的能力。结果Western blot和Dot-ELISA检测显示所制备的HLA-A ＊ 1101抗原肽复合物单体具有天然构象,且可被生物素化;流式细胞仪分析显示所制备的四聚体可与HLA-A11^＋供者的抗原特异性CTL结合。结论成功制备了具有完整构象的生物素化HLA-A ＊ 1101抗原肽复合物单体;此四聚体可以特异检测抗原特异性的细胞毒性T细胞。     

HLA-A*0203-BSP的表达和复性及其四聚体的鉴定

目的：优化诱导条件大批量表达生物素化酶BirA底物肽（BSP）与HLA-A＊0203重链胞外域的融合蛋白（HLA—A＊0203、BSP），并制备负载HLA-A＊0203限制性EB病毒抗原肽EBNA3 596-604的四聚体（HIA—A}0203／SVR）。方法：以HLA—A＊0203-BSP原核表达载体转化E．coli BL21（DE3）菌株，优化诱导条件进行大批量重组蛋白的表达。通过稀释法复性可溶性HLA-A＊0203／SVR单体，然后以BirA对其进行生物素化，并以阴离子交换树脂纯化。将纯化的HLA-A＊0203／SVR单体与荧光素标记的链亲和素按4：1的比例混合形成四聚体，通过对特异性CTL进行染色验证其结合活性。结果：当IPTG的浓度为0．4mmol／L，于37℃诱导过夜后，融合蛋白的表达最多。该重组蛋白相对分子质量（Mr）为34003，与HLA—A＊0203-BSP的理论Mr相一致。该重组蛋白以包涵体形式存在于沉淀部分，约占菌体总蛋白的30％。负载抗原肽的可溶性HLA-A＊0203／SVR单体是在同时存在HLA-A＊0203，BSP、β2微球蛋白及HLA-A＊0203限制性抗原肽SVR的情况下通过稀释法复性而获得。该单体生物素化并纯化后与荧光素标记的链亲和素按4：1的比例混合后即形成四聚体。流式细胞术（FCM）分析证实，该四聚体具有与HLA—A2^＋供者特异性CTL结合的活性。结论：HLA—A＊0203-BSP融合蛋白在优化条件下获得高效表达。以此蛋白制备的HLA-A＊0203／SVR四聚体具有与HLA-A2^＋供者特异性CTL结合的活性，为研究HLA—A＊0203个体EB病毒特异性CTL的免疫应答打下了基础。     

生物素化的HLA-A*2402-抗原肽复合物的制备

目的 制备生物素化的HLA-A＊2402-抗原肽复合物。方法 将原核高效表达的sHLA-A＊2402-BSP融合蛋白及β2m和HLA-A＊2402限制性抗原肽EB病毒BRLF1蛋白中的九肽NH2-TYPVLEEMF-COOH进行稀释、复性、折叠,形成HLA—A＊2402-抗原肽复合物单体,并在BirA酶作用下进行生物素化,使生物素结合到HLA-A＊2402-抗原肽复合物中H链C端的BSP序列上形成生物素化的sHLA—A＊2402-抗原肽复合物单体。利用特异性单克隆克体（W6／32和兔抗人β2微球蛋白抗体）及链霉亲合素进行ELISA和Westem blot,检测稀释复性和生物素化的折叠产物。结果 折叠复合物中,主要含有HLA—A＊2402-肽复合物单体及β2两种成分,其中HLA-A＊2402-肽复合物单体可生物素化。结论 成功制备出生物素化的HLA—A＊2402-抗原肽复合物单体,为进一步构建四聚体及制备人工抗原提呈细胞奠定了基础。     

负载HCMV pp65抗原肽的HLA-A*1101-GPI四聚体的制备和鉴定

为体外复性制备负载人巨细胞病毒(HCMV)pp65抗原肽的HLA-A*1101-GPI四聚体,研究优化HLA-A*1101重链与生物素化酶底物肽融合蛋白(HLA-A*1101-BSP)在大肠杆菌中的诱导表达的温度、时间和诱导剂IPTG浓度,并以抗HLA-A*0201抗血清进行免疫印迹鉴定HLA-A*1101-BSP的表达水平。将初步纯化的HLA-A*1101-BSP与β2-微球蛋白(β2m)和HCMV抗原肽pp6516-24(GPISGHVLK,简称GPI)一起利用稀释法进行重折叠复性,获得可溶性HLA-A*1101-GPI单体,经生物素化和纯化后,与Streptavidin-PE结合成四聚体。流式细胞仪分析显示HLA-A*1101-GPI四聚体具有与特异性细胞毒T细胞(CTL)的结合活性,表明成功获得可溶性HLA-A*1101-GPI四聚体,为研究HLA-A*1101限制性CTL的免疫应答打下基础。     

HLA-A*0201/HPV-18E77-15五聚体的构建及其初步应用

目的构建人乳头状瘤病毒18型（HPV-18）特异性HLA-A2肽五聚体，为HPV-18型抗原特异性细胞毒性T淋巴细胞（CTL）的检测提供直接、有效的方法，并将其初步应用于宫颈癌患者外周血中抗原特异性CTL的检测。方法构建含有HLA-A2-BSP和β2M基因的原核表达载体，并进行表达、复性、鉴定及纯化。再将特异性短肽与HLA-A2-BSP和β2M在体外进行耦合，该复合物经纯化浓缩后进行生物素化。生物素化的产物经纯化浓缩后形成单体，此单体再与藻红蛋白标记的链霉亲和素按一定比例耦合构建成五聚体。运用所构建的五聚体，通过流式细胞仪检测宫颈癌患者外周血中抗原特异性CTL，并与正常对照组进行比较分析。结果所构建的pBV220-HLA-A2-BSP和pBV220-β2M原核表达载体的表达高效而且稳定，纯度达90％以上。HPV-18阳性宫颈癌患者体内抗原特异性CTL计数明显高于对照组（P〈0．05）。结论在五聚体复合物的构建中，高效、稳定的pBV220-HLA-A2-BSP和pBV220-β2M原核表达载体是构建成功的基础。所构建的MHC I类分子五聚体和传统的四聚体相比，作为体内、外HPV-18E7抗原特异性CTL检测的有效工具，具有一定优势。     

sHLA-A*0201-抗原肽四聚体的构建与功能检测

目的：构建有功能的sHLA-A＊0201-抗原肽四聚体，建立一套HLA Ⅰ类分子／抗原肽的四聚体制备技术。方法：利用基因工程及体外折叠技术构建sHLA-A＊0201-LMP2A426-434复合物分子，并在BirA酶的作用下生物素化。与荧光标记的亲和素衍生物以分子数4：1结合而形成HLA-A＊0201-LMP2A426-434四聚体。获得的四聚体对长期混合淋巴细胞培养中增殖的抗原特异性CTL进行检测，同时用细胞毒实验验证。结果：荧光标记的亲和素与生物素化的HLA-A＊0201-抗原肽复合物分子正确结合，制备的四聚体能够与长期混合淋巴细胞培养出的特异性T细胞结合。结论：从结构与功能上证实成功地获得有功能的HLA-A＊0201-抗原肽复合物四聚体。为进一步研究T细胞识别机制与功能奠定了基础，也为过程复杂的HLA-抗原肽四聚体制备提供了可行的免疫学监控方法。     

HBV抗原肽-HLA-A*2402复合物四聚体的构建及初步检测应用

目的：构建2种HBV抗原肽-HLA-A＋2402复合物四聚体，并初步用该2种四聚体检测针对不同抗原肽特异性的细胞毒性T细胞（CTL）。方法：原核高效表达HLA-A＋2402-BSP和β2m蛋白后，分别与乙型肝炎病毒抗原肽P01756-764和Corell7-125在体外复性折叠成可溶性的HLA-A＋2402抗原肽复合物单体，经BirA酶作用并通过凝胶过滤层析法纯化复合物单体，分别将复合物单体与藻红蛋白标记的链霉亲和素按一定比例耦合构建成2种HBV抗原肽四聚体。最后进行流式细胞术检测。结果：Dot-ELISA和ELISA检测显示获得了2种具有天然构象的生物素化的HBV抗原肽-HLA-A＋2402复合物单体。结论：构建的2种四聚体可以检测乙型肝炎感染者体内特异性的CTL。     

三种常见HBV抗原肽-HLA-A*0201复合物四聚体的构建及初步检测应用

目的 体外构建三种常见HBV抗原肽-HLA-A*0201复合物四聚体,并初步用该三种四聚体对抗原肽特异性的细胞毒性T细胞(CTL)进行了初步检测.方法 原核高效表达的HLA-A*0201-BSP和β2m蛋白,分别和三种HBV抗原肽(HBVCore18-27,Env335-343,Po1575-583)体外复性折叠成可溶性的HLA-A*0201抗原肽复合物单体,经BirA酶作用并通过凝胶过滤层析法纯化复合物单体,分别将复合物单体与藻红蛋白标记的链霉亲和素按一定比例耦合构建成相应的三种抗原肽四聚体.最后进行流式细胞仪检测.结果 Dot-ELISA和ELISA检测显示获得了三种具有天然构象的生物素化的HBV抗原肽-HLA-A*0201复合物单体.构建的三种四聚体均可以检测到相应特异性的CTL,在自限性感染患者体内针对乙肝核心抗原(core18-27)的CTL细胞频数(0.18%)高于针对聚合酶抗原(po1575-583)(0.08%)和包膜抗原(env335-343)(0.06%).结论 成功构建了三种具有完整构象的生物素化HBV抗原肽-HLA-A*0201复合物单体,所构建的三种四聚体都可以检测到抗原特异性的CTL.     

制备HLA-A*0201型NLVPMVATV肽四聚体用于巨细胞病毒特异CTL检测

目的制备HLA-A＊0201型NLVPMVATV肽四聚体，用于检测病人的巨细胞病毒（CMV）特异CTL，指导临床用药。方法工程菌以包涵体的形式表达HLA-A＊0201型α链和β2m，对包涵体进行洗涤、变性后，在NLVPMVATV肽存在的情况下，在复性液中加入适量的α链和β2m，共同复性形成单聚体，单聚体浓缩后进行生物素化，再纯化浓缩，与PE标记的链亲和素反应，形成四聚体。结果用制备的四聚体-PE和购买的CD8-FITC能双标记CMV特异CTL，用于流式细胞仪检测。结论成功地制备了四聚体-PE，可用于病人外周血的CMV特异CTL检测，由此可知病人的细胞免疫功能。     

HLA-A*0206-BSP和-A*0207-BSP融合基因的构建与表达

采用RT-PCR技术从HLA-A*0206和-A*0207阳性个体的PBMC中分别克隆出HLA-A*0206和-A*0207基因的全长cDNA序列,构建HLA-A*0206和-A*0207克隆载体。再利用PCR技术从构建的克隆载体中扩增HLA-A*0206和-A*0207的α链(重链)胞外段序列,分别经双酶切置换本室保存的HLA-A*0201-BSP重组体中的HLA-A*0201胞外段序列,使HLA-A*0206和-A*0207与BirA酶底物肽(BirA substrate peptide,BSP)序列融合,构建HLA-A*0206-BSP和-A*0207-BSP融合基因的表达载体,经限制性酶切和DNA测序证实。然后将该表达载体转化E.coliBL21(DE3)后获得表达产物,通过体外稀释复性,初步纯化的表达产物通过ELISA和Western blot检测证明能够与β2微球蛋白(HLA I类分子轻链)及HLA-A2限制性抗原肽(HBV core 18-27)折叠形成具有HLA I类分子天然构象的抗原肽/HLA-A2复合物单体。为进一步构建HLA-A*0206和-A*0207四聚体,探讨相应HLA-A2亚型的功能特点提供了物质基础。     

抗巨细胞病毒早晚期抗原单克隆抗体制备及在病毒培养物鉴定中的初步应用

目的 制备抗CMV早晚期抗原单克隆抗体并在病毒培养物鉴定中初步应用.方法 CMV感染MRC-5细胞24h、48h和72h后甲醛灭活的可溶性抗原免疫BALB/c小鼠,小鼠脾细胞与骨髓瘤细胞NS-1进行融合.酶免法筛查阳性杂交瘤并有限性稀释法进行克隆.免疫荧光及印迹对筛选后的克隆进行鉴定,最终获得的杂交瘤制备腹水并使用Protein G进行纯化.纯化后单抗应用于CAP室间质评标本以及临床标本CMV培养物的鉴定.结果 3只小鼠脾细胞与骨髓瘤细胞融合后初步筛查出约110株阳性克隆.剔除与其它抗原有交叉反应、抗体效价低、非全覆盖早晚期抗原的克隆最终获得抗CMV单抗杂交瘤1株,即23B5-1.免疫荧光显示23B5-1株单抗与CMV感染后3h-120h的MRC-5细胞均反应,即覆盖即刻、早期和晚期抗原.免疫印迹试验显示23B5-1株单抗与CMV抗原25KD-50KD之间的5个蛋白条带结合.23B5-1株单抗免疫球蛋白亚型为IgG1.Protein G纯化腹水后的单抗效价≥1∶12800.纯化单抗染色鉴定6份室间质评及10份临床标本CMV培养物全部符合.结论 初步应用显示制备的抗CMV早晚期抗原单克隆抗体性能良好.     

Identification of a dominant immunogenic epitope of the nucleocapsid (HBc) of the hepatitis B virus

Four monoclonal antibodies to hepatitis B core antigen are described. The antibodies bind to the same or a very closely related epitope. Antibodies to this dominant epitope are present in the sera of patients with either acute or chronic hepatitis B virus (HBV) infection. A high percentage of inhibition of the binding of these antibodies to the core antigen by these four monoclonal antibodies suggests that the core antigen has a restricted antigenicity in man. Radiolabeled or peroxidase labeled forms of these monoclonal antibodies can be used to assay IgM and total anticore in serum.     

The Fertilization Antigen (FA-1): Applications in Immunocontraception and Infertility in Humans

ABSTRACT: GB24 is a mouse monoclonal antibody (IgG1) raised against human term placental microvilli. This antibody displayed pan-trophoblast reactivity pattern. In addition, GB24 recognized normal peripheral leukocytes and transformed cell lines (Daudi, HL-60, Jurkat, AV₃, BeWo, HT-29) by using membrane immunofluorescence and flow cytometry. By SDS-polyacrylamide gel electrophoresis, this antibody immunoprecipitated two proteins of 62 kilodaltons (kDa) and 75 kDa from placental microvilli. Isoelectrofocusing analysis revealed that these two bands exhibited different isoelectric points: 4.7 for the 62 kDa protein, 4.6 and 4.4 for the two spots corresponding to the 75 kDa protein. Microvilli from different placentae revealed substantial differences regarding the intensity of the labeling of these two bands, suggesting that the antigens recognized by GB24 are probably allotypic.     

Evaluation of a newly developed HIV antigen test

A new monoclonal antibody-based enzyme immunoassay (Innogenetics) for the detection and quantification of p24 core antigens of HIV-1 (group M and group O) and of HIV-2 was evaluated on 2745 serum samples and 18 culture supernatants and compared with a reference (Coulter) HIV-1 p24 antigen assay. Positive results were confirmed by neutralization with the reagents of the respective tests. As demonstrated by dilution series of HIV cocultures, the new test recognizes p24 antigen of the most common HIV genetic subtypes, including group O and HIV-2. Titres ranged from 729 to 531441. Therefore p24 antigen assay is but very weakly reactive with HIV-2 (titres from 9 to 81). The new test is considerably more sensitive than the reference. In a population of 365 follow-up samples from 86 different patients, representing all stages of infection, the new test detected p24 antigen at least once in 52% (45/86) of these patients, whereas the reference was positive in 31% (27/86). The newly designed test detected antigen in 40% (145/365) of the samples, while the reference was positive in 21% (75/365). In a group of PCR and/or culture positive neonates, 33% (9/27) of the samples were positive with the new test versus 18% (5/27) with the reference. The specificity of the new test, as determined on 2,000 blood donor samples, was 99.65% (initially), 99.80% (after repetition), and 100% (with neutralization). The reference scored 99.95%, 100%, and 100%, respectively. In 300 seronegative samples from persons at risk, the initial specificity of the new test was 98.67% (the reference, 99.00%). With neutralization, both assays were 100% specific. J. Med. Virol. 53:31–35, 1997. © 1997 Wiley-Liss, Inc.     

三种血清标志物检测在结直肠癌诊断中的应用价值

目的 研究血清肿瘤标志物联合检测在结直肠癌患者诊断中的应用价值.方法 收集2010年1月至2012年9月河北医科大学第三医院肛肠科收治的120例结直肠癌患者作为观察组,80例结直肠良性疾病患者作为良性对照组,100例健康体检者作为健康对照组,采用全自动电化学发光仪检测各组患者外周血中癌胚抗原（CEA）、糖类抗原（CA）199和CA242的含量.对比观察组不同TNM分期患者之间外周血CEA、CA199和CA242水平;分析3项指标联合检测诊断结直肠癌的灵敏度和特异度.结果 观察组患者CEA、CA199和CA242水平明显高于良性对照组和健康对照组,并且在观察组患者3项指标水平均为TNM Ⅰ期＞Ⅱ期＞Ⅲ期＞Ⅳ期.3项指标联合检查灵敏度为80.00％,特异度为97.78％,均高于3项指标单独检测（灵敏度和特异度分别为CEA：17.50％、73.89％,CA199：29.17％、67.22％,CA242：71.67％、68.89％,均P＜0.05）.结论 CEA、CA199和CA242联合检查能提高结直肠癌诊断的灵敏度和特异度,具有积极的临床价值.     

The Diversity of Antigen-Specific TCR Repertoires Reflects the Relative Complexity of Epitopes Recognized

Antigen-selected T cell receptor (TCR) repertoires vary in complexity from very limited to extremely diverse. We have previously characterized two different CD8 T cell responses, which are restricted by the same mouse major histocompatibility complex (MHC) class I molecule, H-2 K^d. The TCR repertoire in the response against a determinant from Plasmodium berghei circumsporozoite protein (PbCS; region 252–260) is very diverse, whereas TCRs expressed by clones specific for a determinant in region 170–179 of HLA-CW3 (human) MHC class I molecule show relatively limited structural diversity. We had already demonstrated that cytolytic T lymphocyte (CTL) clones specific for the PbCS peptide display diverse patterns of antigen recognition when tested with a series of single Ala-substituted PbCS peptides or mutant H-2 K^d molecules. We now show that CW3-specific CTL clones display much less diverse patterns of recognition. Our earlier functional studies with synthetic peptide variants suggested that the optimal peptides recognized were 9 (or 8) residues long for PbCS and 10 residues long for CW3. We now present more direct evidence that the natural CW3 ligand is indeed a 10-mer. Our functional data together with molecular modeling suggest that the limited TCR repertoire selected during the CW3 response is not due to a paucity of available epitopes displayed at the surface of the CW3 peptide/K^d complex. We discuss other factors, such as the expression of similar self MHC peptide sequences, that might be involved in trimming this TCR repertoire.     

A radioimmunoprecipitation polyethylene glycol assay for circulating Entamoeba histolytica antigens

An assay capable of detecting circulating Entamoeba histolytica antigens in amoebiasis is described. This assay utilised a radiolabelled affinity purified rabbit anti-E. histolytica antibody that had been depleted of antibodies that cross-react with human serum proteins, and a polyethylene glycol precipitation step.     

PHA对人扁桃体T淋巴细胞亚群变化及活化抗原表达的效应

应用FITC和PE双色荧光试剂并经流式细胞计分析了人扁桃腺T淋巴细胞亚群组成,以及用PHA刺激后T淋巴细胞亚群的变化和活化抗原的表达情况。结果表明:1)人扁桃体T淋巴细胞以CD4~+细胞占优势,CD4~+与CD8~+细胞比值约为5.32±0.55;2),经PHA刺激培养72小时,CD4~+CD8~+细胞明显增加;3)经PHA刺激培养后,IL-2受体(CD25)和HLA-DR抗原表达增加。本实验结果为深入研究人扁桃体T淋巴细胞的表型变化提供了客观指标,对进一步探讨其在免疫系统中的作用具有一定的意义。     

Exponential Rise in Prostate-Specific Antigen (PSA) during Anti-Androgen Withdrawal Predicts PSA Flare after Docetaxel Chemotherapy in Patients with Castration-Resistant Prostate Cancer

PurposeTo investigate the relationship between rising patterns of prostate-specific antigen (PSA) before chemotherapy and PSA flare during the early phase of chemotherapy in patients with castration-resistant prostate cancer (CRPC).ResultsThere were two growth patterns of PSA doubling time: 22 patients (40.0%) had a steady pattern with a more prolonged PSADT2 than PSADT1, while 33 (60.0%) had an accelerating pattern with a shorter PSADT2 than PSADT1. During three cycles of chemotherapy, PSA flare occurred in 11 patients (20.0%); of these patients, 3 were among 33 (9.1%) patients with an accelerating PSA growth pattern and 8 were among 22 patients (36.4%) with a steady PSA growth pattern (p=0.019). Multivariate analysis showed that only PSA growth pattern was an independent predictor of PSA flare (p=0.034).ConclusionAn exponential rise in PSA during anti-androgen withdrawal is a significant predictor for PSA flare during chemotherapy in CRPC patients.