用重组抗原检测鼻咽癌病人血清IgA／gp125抗体

用重组抗原检测鼻咽癌病人血清ＩｇＡ／ｇｐ１２５抗体薛绍礼１皮国华２谷淑燕２李平１抗Ｅｐｓｔｅｉｎ－Ｂａｒ病毒（ＥＢＶ）壳抗原（ＶＣＡ）ＩｇＡ抗体，是鼻咽癌（ＮＰＣ）早期诊断的一个重要血清学指标。曾先后用免疫荧光法（ＩＦ）和免疫酶法（ＩＥ）进行检测［１...     

抗Epstein－Bars病毒壳抗原gp125单克隆抗体的研制

用重组痘苗病毒在１４３细胞上表达的ｇＰ１２５粗提物免疫Ｂａｌｂ／Ｃ小鼠，用杂交瘤技术获得７株稳定分泌抗Ｅｐｓｔｅｉｎ－Ｂａｒｓ（ＥＢ）病毒ｇｐ１２５单克隆抗体的杂交瘤细胞株。对杂交瘤细胞及单克隆抗体进行一系列分析和鉴定，初步建立了用表达产物及特异性单克隆抗体检测ＥＢ病毒ＩｇＡ／ｇｐ１２５抗体的三步ＥＬＩＳＡ法。用此法检测ＩｇＡ／ＶＣＡ阳性的鼻咽癌病人血清及ＩｇＡ／ＶＣＡ阴性的正常人血清，结果完全吻合。     

Epstein-Barr病毒壳抗原的纯化及其在检查血清抗体中的应用

为了建立纯化Ｅｐｓｔｅｉｎ－Ｂａｒｒ（ＥＢ）病毒壳抗原（ＥＢＶ－ＶＣＡ）的方法，用于酶联免疫吸附试验（ＥＬＩＳＡ）检测人血清中的相关抗体，我们用重组昆虫病毒在感染的ｓｆ９细胞中表达ＥＢＶ－ＶＣＡ。感染的细胞经裂解后，层析纯化表达产物。用纯化的ＶＣＡ作为抗原包被ＥＬＩＳＡ板或硝基纤维膜，检查血清中ＶＣＡ／ＩｇＡ和ＶＣＡ／ＩｇＧ抗体，为ＥＢＶ感染的检测和ＮＰＣ的诊断发展了一个敏感、特异和简便的方法。     

Epstein—Barr病毒壳抗原的纯化及其在检查血清抗体…

为了建立纯化Ｅｐｓｔｅｉｎ－Ｂａｒｒ（ＥＢ）病毒壳抗原（ＥＢＶ－ＶＣＡ）的方法，用于酶联免疫吸附试验（ＥＬＩＳＡ）检测人因清中的相关抗体，我们用重组昆虫病毒在感染的ｓｆ９细胞中表达ＥＢＶ－ＶＣＡ。感染的细胞经裂解后，层析纯化表达产物。用经的ＶＣＡ作为抗原包虫被ＥＬＩＳＡ板或硝基纤维膜，检查血清中ＶＣＡ／ＩｇＡ和ＶＣＡ／ｇＧ抗体，为ＥＢＶ感染的的检测和ＮＰＣ的诊断发展了一个敏感、特异和简便的方法。     

人巨细胞病毒单克隆抗体的研制检定和应用

采用人巨细胞病毒（ＨＣＭＶ）ＡＤ１６９株作为免疫原，制备出１３株鼠－鼠杂交瘤细胞系。对其中的６株进行了检定．免疫印迹试验结果表明：单克隆抗体（ＭｃＡｂ）７Ｂ４、７Ｄ７、７Ｅ１１、８Ｅ８和８Ｄ６相对应的ＨＣＭＶ多肽分子量分别为４６、１５０、３８、５１７２和６５ｋＤ．ＨＣＭＶ感染人胚肺二倍体细胞（２ＢＳ）后不同时间制成抗原片，与ＭｃＡｂ作间接免疫荧光试验。结果表明：ＭｃＡｂ８Ｂ８相应的病毒多肽为即刻早期抗原，其它５株ＭｃＡｂ相应的病毒多肽均为晚期抗原，６株ＭｃＡｂ等量混合后，标上辣根过氧化物酶，用于ＩｇＭ抗体捕获法ＥＬＩＳＡ（ＭａｃＥＬＩＳＡ）中，并与间接ＥＬＩＳＡ（ＩＥＬＩＳＡ）同时检测ＨＣＭＶ－ＩｇＭ．在未经选择的１００份脐带血中，两法均为阳性的３份，两法均为阴性的９４份；ＭａｃＥＬＩＳＡ阳性而ＩＥＬＩＳＡ阴性的２份血清的特异性试验证明，ＨＣＭＶ－ＩｇＭ确为阳性．ＩＥＬＩＳＡ阳性而ＭａｃＥＬＩＳＡ阴性的１份血清的特异性试验证明，它是由ＲＦ引起的假阳性。     

用合成肽抗原检测Epstein—Barr病毒抗体

用合成肽抗原检测Ｅｐｓｔｅｉｎ－Ｂａｒ病毒抗体刘海鹰周玲邓洪周维雅Ｊ．Ｍｉｄｄｅｌｄｏｒｐ曾毅Ｅｐｓｔｅｉｎ－Ｂａｒ病毒（ＥＢＶ）进入宿主细胞后能产生多种由ＥＢＶ决定的抗原，包括早期抗原（ＥＡ），壳抗原（ＶＣＡ）和核抗原（ＥＢＮＡ）等。这些由ＥＢＶ基...     

基因重组Epstein—Barr病毒壳抗原gp125的免疫原性

天然的Ｅｐｓｔｅｉｎ－Ｂａｒｒ病毒ｇｐ１２５蛋白有极强的免疫原性，是ＥＢＶ初次感染的主要免疫原，也是诊断ＥＢＶ既往感染和新近感染最有价值的抗原。文章在用重组痘苗病毒表达ｇｐ１２５的基础上，研究了表达产物的特异性，并用活的重组痘苗病毒免疫中国本兔，用表达产物免疫ＢＡＬＢ／Ｃ小鼠，研究了其免疫原性和免疫抗体的特异性。结果显示：重组痘苗病毒在感染细胞内特异性地表达ｇｐ１２５，活病毒及表达产物能诱导动物产     

抗人免疫缺陷病毒1型gp120人源单链抗体的表达

目的研究人源抗人免疫缺陷病毒１型（ＨＩＶ－１）ｇｐ１２０单链抗体（ＳｃＦｖ）。方法以人工合成的ＨＩＶ－ｌｇｐ１２０Ｖ３环多肽为抗原，利用噬菌体抗体库技术，筛选含有抗－ｇｐ１２０ＳｃＦｖ基因的噬菌体，提取质粒，转化大肠杆菌ＨＢ２１５１，表达可溶性ＳｃＦｖ。结果经ＳＤＳ－ＰＡＧＥ和Ｗｅｓｔｅｒｎｂｌｏｔ分析，表达产物分子量为２８ｋＤ左右，且具有ｃ－ｍｙｃ活性；ＥＬＩＳＡ和Ｄｏｔｂｌｏｔ结果表明，可溶性ＳｃＦｖ具有较好的抗原结合活性和较强的特异性；竞争性ＥＬＩＳＡ实验结果进一步证明表达产物的特异抗－ｇｐ１２０活性。结论该技术便捷有效，可大量获得人源抗ＨＩＶ抗体片段，为进一步研究抗ＨＩＶ抗体的生物活性和ＨＩＶ感染诊治打下基础     

Epstein－Barr病毒膜抗原gp250／350在CHO细胞中高表达株的初筛

Ｅｐｓｔｅｉｎ－Ｂａｒｒ病毒膜抗原ｇｐ２５０／３５０在ＣＨＯ细胞中高表达株的初筛周玲，曾毅Ｈ．Ｗｏｌｆ使用Ｈ．Ｗｏｌｆ教授研究所以前构建的Ｅｐｓｔｅｉｎ－Ｂａｒｓ病毒（ＥＢＶ）重组ＤＮＡ质粒ＰＭＤⅢＧＰＴＲ（移去穿膜序列），用此质粒转化ＣＨＯ细胞。经...     

用基因工程表达的抗原早期诊断鼻咽癌

目的为了建立鼻咽癌（ＮＰＣ）早期诊断方法。方法以基因工程表达的、经纯化的ＥＢ病毒（Ｅｐｓｔｅｉｎ－Ｂａｒｖｉｒｕｓ，ＥＢＶ）早期抗原（ＥＡ）成分ＥＡ－Ｄ和ＥＡ－Ｒ作为诊断抗原，建立了酶联免疫吸附试验（ＥＬＩＳＡ），检查３０例ＮＰＣ病人及４９例正常人血清中的ＥＡ／ＩｇＡ抗体。结果用ＥＬＩＳＡ检测抗体较用细胞涂片免疫酶方法（ＩＥ）敏感。ＥＬＩＳＡ检测ＮＰＣ病人血清中ＥＡ／ｌｇＡ抗体，阳性率为１００％，ＥＡ／ｌｇＡ抗体效价均≥１∶１００。而用ＩＥ法，平行检测３０例ＮＰＣ病人血清中ＥＡ／ｌｇＡ抗体效价，结果６例为阴性（＜１∶１０），抗体阳性率为７０％。ＥＬＩＳＡ明显地提高了ＮＰＣ的检出率。以ｐ１３８（ＥＡ－Ｒ）和ｐ５４（ＥＡ－Ｄ）分别或混合包被，检测对ＥＢＶ特异的ＥＡ－Ｄ和ＥＡ－Ｒ的抗体。结论表明在ＮＰＣ病人血清中存在对ＥＡ两种抗原的抗体，对ＥＡ－Ｄ的抗体滴度高于对ＥＡ－Ｒ的抗体。因此，以两种抗原混合包被作为诊断抗原建立的ＥＬＩＳＡ方法，为ＮＰＣ的早期诊断提供更敏感、特异和简便的手段。     

Antibodies to Epstein-Barr virus in nasopharyngeal carcinoma, tonsillar carcinoma and control groups

In the sera of 17 patients with nasopharyngeal carcinoma (NPC) and of 19 patients with tonsillar carcinoma (TC) the titres of IgA, IgG and IgM antibodies to EBV VCA (viral capsid antigen) and of IgG antibodies to EBV EA (early antigen) were determined by the indirect immunofluorescence (IF) method. Significant difference was observed in the frequency of IgA antibodies to EBV VCA and IgG antibodies to EBV EA between NPC patients and controls. There was also a significant difference between the frequency of IgM antibody to EBV VCA and EBV EA antibody titres in TC patients and controls. The geometric mean titre (GMT) of IgG antibodies to EBV VCA was significantly higher in the NPC and TC patients as compared to controls.     

Seroepidemiological study of Epstein-Barr virus infection in Bangladesh

A seroepidemiological study was carried out on 502 sera to determine the prevalence of EBV infection in a group of Bangladeshi people (age range: 15 days–90 years). All sera were tested for IgG antibody to the EBV viral capsid antigen (VCA) by a commercially available enzyme linked immunosorbent assay (ELISA) and the negative sera were checked subsequently by indirect immunofluorescence (IF) methods. The prevalence of EBV infection in the study group was 81.27%. 42.37% of infants had antibodies to EBV by the age of 1 year. A significant rise in the percentage of seropositives between 0–1- and 1–2-year-old children was demonstrated, indicating a high rate of primary infection at these ages. The prevalence of IgG antibody to VCA was 87.93% in the 2–10 years age group and was sustained at over 85% thereafter. Higher ELISA values were more common both in the 0–2- and >25-year age groups, the latter being statistically significant (P < 0.025). Similar higher values were also observed in females as compared to males (P = 0.05). Eighteen out of 109 negative sera and two equivocal sera by ELISA were found to be positive by indirect IF, indicating a negative predictive value of 82% for ELISA. The concordance between the two methods was 97% with ELISA proving to be less sensitive than indirect IF. It is concluded that the prevalence of EBV infection in Bangladeshi population is similar to that observed in other developing countries and that ELISA can be used for seroepidemiological surveys; however, the sera negative by ELISA should be checked routinely by indirect IF. © 1996 Wiley-Liss, Inc.     

High incidence of elevated antibody titers to Epstein-Barr virus in patients with uveitis

Summary. We assayed Epstein-Barr virus (EBV) antibody titers in patients’ sera using indirect immunofluorescence and tested for the presence of antibody to EBV immediate-early BZLF1 protein ZEBRA by Western blotting to explore the association of EBV infection with uveitis. IgG and IgA antibodies to viral capsid antigen (VCA), IgG antibodies to early antigen (EA), and antibodies to EBV nuclear antigen were detected at higher titers in sera of patients with uveitis than in the sera of healthy controls. Neither IgM antibody to VCA nor EA was detected in the patients’ sera. Anti-ZEBRA-IgG antibodies were detected in most patients’ sera, but not in those of healthy controls. These results suggest that uveitis might be a disease accompanied by EBV reactivation.     

Detection of IgA antibodies to Epstein-Barr virus-associated antigens by ELISA

The detection of IgA antibodies to the Epstein-Barr virus (EBV)-associated viral capsid antigen (VCA) and early antigens (EA) is of diagnostic and prognostic importance for patients with nasopharyngeal carcinoma (NPC). An ELISA for the determination of serum IgG antibodies to these antigens has been developed which uses the double antibody method. 136 sera obtained from healthy donors and patients with non-EBV related tumors and lymphomas were tested by ELISA; only 3 sera, from patients with chronic lymphatic leukemia, hairy cell leukemia and Burkitt-like lymphoma, contained antibodies of IgA class to VCA and EA. Ninety-five sera from patients suspected of having NPC were tested. IgA anti-VCA was found in 28 sera (29.5%), 12 of which also contained IgA anti-EA. The assays described are suitable for diagnosis and follow-up of patients with EBV-associated nasopharyngeal carcinoma. Furthermore, isolated EA components may be tested for their reactivity with IgA antibodies, as was shown for the 60 kDa polypeptide associated with the EA complex.     

Improved sensitivity of detection by avidin-biotin complex (ABC) immunocytochemistry in Epstein-Barr virus serology

Serum antibodies against Epstein-Barr virus (EBV)-determined antigens have traditionally been titrated by the indirect immunofluorescence (IIF) technique. The avidin-biotin complex (ABC) immunocytochemical technique was used to determine the serum levels of IgA against EBV viral capsid antigen (IgA/VCA) and IgA against EBV early antigen (IgA/EA) in sera of 106 nasopharyngeal carcinoma (NPC) patients prior to treatment and 100 normal individuals. The sensitivity of the ABC technique is enhanced by an amplification of the antigen-antibody reaction, which involves the binding of the enzyme-linked ABC to the second biotinylated antibody. There was a good correlation (r = 0.9988) between ABC and IIF-determined IgA/VCA-positive titres, with the ABC technique being more sensitive than IIF in the detection of IgA/VCA in NPC sera: 94% (99/106) and 76% (80/106), respectively. The frequency of IgA/EA reactivity in NPC sera was also markedly increased by immunodetection with the ABC technique as compared with IIF technique: 63% (69/106) and 28% (30/106) respectively. Both the immunocytochemical techniques were equally specific in discriminating between elevated serum titres of IgA/VCA and IgA/EA in NPC sera from normal human sera.     

Evaluation of Epstein-Barr virus antigen-based immunoassays for serological diagnosis of nasopharyngeal carcinoma

BACKGROUND: Immunofluorescence (IF) assays based on Epstein-Barr virus (EBV)-encoded antigens have traditionally been the preferred approach for serological screening of nasopharyngeal carcinoma (NPC). OBJECTIVES: To compare the performance of two new commercial assays (indicated by COMM) using, respectively, the IF and enzyme-linked immunosorbent assay (ELISA) formats with an in-house IF assay (IFA). STUDY DESIGN: Sera from 163 patients with histologically confirmed NPC, and 98 healthy controls were tested with each of these assays and their results compared. RESULTS: The sensitivity, specificity, positive and negative predictive values, respectively, for the COMM VCA IgA ELISA were 92.6%, 94.9%, 96.8%, 88.6%; for the COMM VCA IgA IFA were 96.9%, 41.8%, 73.5%, 89.1%; for the in-house VCA IgA IFA were 98.2%, 72.4%, 85.6%, 95.9%; for the COMM EA IgA ELISA were 46.6%, 100%, 100%, 53.0%; for the COMM EA IgA IFA were 77.3%, 100%, 100%, 72.6%; and for the in-house EA IgA IFA were 77.9%, 99.0%, 99.2%, 72.9%. CONCLUSIONS: The receiver operating characteristic curves comparison showed a marginal superior accuracy for the COMM VCA IgA ELISA, suggesting this to be used as a high-throughput serological screening assay, with the more specific COMM EA IgA IFA as a follow-up confirmatory assay in this NPC-endemic area.     

Comparison of three different serological techniques for primary diagnosis and monitoring of nasopharyngeal carcinoma in two age groups from Tunisia

Nasopharyngeal carcinoma (NPC) in Tunisia is characterized by its bimodal age distribution involving juvenile patients of 10-24 years and adult patients of 40-60 years. Three serological techniques were compared for primary diagnosis (N = 117) and post-treatment monitoring (N = 21) of NPC patients separated in two age groups. Immunofluorescence assay (IFA) was used as the "gold standard" for detection of IgG and IgA antibodies reactive with Epstein-Barr virus (EBV) early (EA) and viral capsid (VCA) antigens. Results were compared with ELISA measuring IgG and IgA antibody reactivity to defined EBNA1, EA, and VCA antigens. Immunoblot was used to reveal the molecular diversity underlying the anti-EBV IgG and IgA antibody responses. The results indicate that young NPC patients have significantly more restricted anti-EBV IgG and IgA antibody responses with aberrant IgG VCA/EA levels in 78% compared to 91.7% in elder patients. IgA VCA/EA was detected in 50% of young patients versus 89.4% for the elder group (P < 0.001). Immunoblot revealed a reduced overall diversity of EBV antigen recognition for both IgG and IgA in young patients. A good concordance was observed between ELISA and IFA for primary NPC diagnosis with 81-91% overall agreement. Even better agreement (95-100%) was found for antibody changes during follow-up monitoring, showing declining reactivity in patients in remission and increasing reactivity in patients with persistent disease or relapse. ELISA for IgA anti-VCA-p18 and immunoblot proved most sensitive for predicting tumor relapse. VCA-p18 IgA ELISA seems suitable for routine diagnosis and early detection of NPC complication.     

Evaluation of Epstein-Barr virus antigen-based immunoassays for serological diagnosis of nasopharyngeal carcinoma

BackgroundImmunofluorescence (IF) assays based on Epstein-Barr virus (EBV)-encoded antigens have traditionally been the preferred approach for serological screening of nasopharyngeal carcinoma (NPC).ObjectivesTo compare the performance of two new commercial assays (indicated by COMM) using, respectively, the IF and enzyme-linked immunosorbent assay (ELISA) formats with an in-house IF assay (IFA).Study designSera from 163 patients with histologically confirmed NPC, and 98 healthy controls were tested with each of these assays and their results compared.ResultsThe sensitivity, specificity, positive and negative predictive values, respectively, for the COMM VCA IgA ELISA were 92.6%, 94.9%, 96.8%, 88.6%; for the COMM VCA IgA IFA were 96.9%, 41.8%, 73.5%, 89.1%; for the in-house VCA IgA IFA were 98.2%, 72.4%, 85.6%, 95.9%; for the COMM EA IgA ELISA were 46.6%, 100%, 100%, 53.0%; for the COMM EA IgA IFA were 77.3%, 100%, 100%, 72.6%; and for the in-house EA IgA IFA were 77.9%, 99.0%, 99.2%, 72.9%.ConclusionsThe receiver operating characteristic curves comparison showed a marginal superior accuracy for the COMM VCA IgA ELISA, suggesting this to be used as a high-throughput serological screening assay, with the more specific COMM EA IgA IFA as a follow-up confirmatory assay in this NPC-endemic area.     

Single-assay combination of Epstein-Barr Virus (EBV) EBNA1- and viral capsid antigen-p18-derived synthetic peptides for measuring anti-EBV immunoglobulin G (IgG) and IgA antibody levels in sera from nasopharyngeal carcinoma patients: options for field screening

Assessment of immunoglobulin A (IgA) antibody responses to various Epstein-Barr virus (EBV) antigen complexes, usually involving multiple serological assays, is important for the early diagnosis of nasopharyngeal carcinoma (NPC). Through combination of two synthetic peptides representing immunodominant epitopes of EBNA1 and viral capsid antigen (VCA)-p18 we developed a one-step sandwich enzyme-linked immunosorbent assay (ELISA) for the specific detection of EBV reactive IgG and IgA antibodies in NPC patients (EBV IgG/IgA ELISA). Sera were obtained from healthy donors (n = 367), non-NPC head and neck cancer patients (n = 43), and biopsy-proven NPC patients (n = 296) of Indonesian and Chinese origin. Higher values of optical density at 450 nm for EBV IgG were observed in NPC patients compared to the healthy EBV carriers, but the large overlap limits its use for NPC diagnosis. Using either EBNA1 or VCA-p18 peptides alone IgA ELISA correctly identified 88.5% and 79.8% of Indonesian NPC patients, with specificities of 80.1% and 70.9%, whereas combined single-well coating with both peptides yielded sensitivity and specificity values of 90.1 and 85.4%, respectively. The positive and negative predictive values (PPV and NPV, respectively) for the combined EBNA1 plus VCA EBV IgA ELISA were 78.7% and 93.9%, respectively. In the Indonesia panel, the level of EBV IgA reactivity was not associated with NPC tumor size, lymph node involvement, and metastasis stage, sex, and age group. In the China panel the sensitivity/specificity values were 86.2/92.0% (EBNA1 IgA) and 84.1/90.3% (VCA-p18 IgA) for single-peptide assays and 95.1/90.6% for the combined VCA plus EBNA1 IgA ELISA, with a PPV and an NPV for the combined EBV IgA ELISA of 95.6 and 89.3%, respectively. Virtually all NPC patients had abnormal anti-EBV IgG diversity patterns as determined by immunoblot analysis. On the other hand, healthy EBV carriers with positive EBV IgA ELISA result showed normal IgG diversity patterns. By using EBV IgG immunoblot diversity as confirmation assay for EBV IgA ELISA-positive samples, the sensitivity and specificity for NPC diagnosis increased to 98% and 99.2%, respectively, in the Indonesian NPC samples. The use of these combined methods for seroepidemiological screening studies is proposed.     

Evaluation of four commercial systems for the diagnosis of Epstein-Barr virus primary infections

To compare the performance of four diagnostic commercial systems for Epstein-Barr virus (EBV) serology (for IgM and IgG virus capsid antigen [VCA] and EBV nuclear antigen [EBNA] antibodies), a collection of 125 samples from clinically suspected infectious mononucleosis cases was studied. Indirect immunofluorescence (IIF) for VCA IgM and IgG antibodies and anticomplement immunofluorescence for EBNA antibodies (Meridian Bioscience Inc.) were used as reference methods. By these methods, the cases were classified EBV primary infection (presence of IgM to VCA or IgG to VCA in the absence of EBNA antibodies; n = 82), EBV past infection (presence of VCA IgG and EBNA antibodies in the absence of VCA IgM; n = 26), or no infection (negative for the three markers; n = 17). The following systems were tested: two chemiluminescent immunoassays (CLIAs; the Liason [CLIA-L; DiaSorin] and the Immulite 2000 [CLIA-I; Siemens]), immunofiltration (IF; All.Diag), and an enzyme-linked immunosorbent assay (ELISA; DiaSorin). In the IgM assays, sensitivities ranged from 67.1% (ELISA) to 92.2% (CLIA-L) and specificities ranged from 93.8% (CLIA-L) to 100% (IF). In the VCA IgG assays, sensitivities varied from 79.4% (IF) to 94.4% (CLIA-I) and specificities varied from 94.4% (IF and CLIA-L) to 100% (CLIA-I and ELISA). In EBNA assays, sensitivities ranged from 78.1% (IF) to 93.8% (CLIA-I) and specificities ranged from 32.3% (CLIA-L) to 91.4% (IF). In relation to EBV profiles, the corresponding figures for sensitivity (in detecting primary infection) for IF, CLIA-L, CLIA-I, and ELISA were 92.7%, 93.8%, 89%, and 89.6%, respectively, and those for specificity (to exclude primary recent infection) were 90.7%, 94.6%, 97.7%, and 95.2%, respectively. Although there were limitations in some individual markers, especially CLIA-L for EBNA IgG, the systems evaluated appear to be useful for diagnosis of EBV infection.