以Rtac2/3为抗原用于鼻咽癌病人检测的初步研究

目的 在大肠杆菌中表达EBV的早期基因BRLF1，并纯化这个重组蛋白。用纯化的蛋白作为抗原与鼻咽癌（NPC）病人血清中的特异性抗体发生反应，以寻找新的NPC筛检或诊断标志物。方法 用表达和纯化的BRLF1基因C端2／3部分蛋白（Rtae2／3）建立间接ELISA方法，检测了59份NPC患者血清中的抗Paa IgG抗体，同时59份健康者血清作对照。结果 59份NPC患者血清中50份阳性，而59份健康者对照血清中只有7份阳性。NPC组的阳性率与健康对照组之间差异有统计学意义（P〈0．01）。此方法的灵敏度为84．7％，特异性为88．1％。结论 （1）检测人血清中的抗Rta-IgG可以作为NPC诊断的重要标志物之一。（2）如果检测抗Rta-IgG与检测Zebra IgG抗体试验联合使用，用于NPC的筛检和诊断能够进一步提高灵敏度或特异性。     

EBVTK激酶基因在原核细胞中的表达及其在NPC诊断中的意义

目的 探索以Epstein-Barr病毒（EBV）TK激酶为抗原，建立简便、快速、敏感和特异的鼻咽癌（NPC）诊断方法。方法 构建原核表达载体pRSET-TK，在原核细胞BL21（DF3）中获得高效表达的TK激酶，以Western blot检测证明其抗原的特异性和应用于NPC检测的可行性。以纯化的TK激酶为抗原初步建立ELISA检测方法，检测NPC患者血清中TK／IgG抗体。结果 在NPC患者血清中含有特异的针对TK激酶的IgG抗体，Western blot TK/IgG检测的敏感度和特异度均为100％。结论 初步建立了ELISA TK／IgG诊断NPC方法，具有较高的敏感性和特异性。     

EB病毒两种抗体联合检测在鼻咽癌诊断中的应用

目的探讨EB病毒（epstein—barr virus,EBV）抗体在鼻咽癌早期诊断中的应用价值。方法采用酶联免疫吸附试验（ELISA）测定53例鼻咽癌患者、71例鼻部疾病患者和40例正常体检人群血清EBV相关抗体（EBV VCA—IgA和EA—IgA）。结果3组比较,鼻咽癌组血清VCA—IgA的阳性检出率为79．2％,EA-IgA阳性率为50．9％,与其余两组比较差异有统计学意义（P〈0．01）;鼻咽癌组和鼻部疾病组内VCA-IgA和EA-IgA的阳性率比较差异有统计学意义（P〈0．01）;检测鼻咽癌组两项指标的吸光度均值较另两组高;VCA-IgA单独检测及两项联合检测均具有较高的敏感性（79．2％）,EA-IgA单独检测及两项联合检测均具有较强的特异性（93．8％）。结论联合检测鼻咽癌病人血清的VCA—IgA和EA—gA可兼具两者的性能优势,敏感性较高,特异性较强。对鼻咽癌的早期诊断具有重要的临床应用价值。     

五厂家EB病毒抗体检测试剂盒血清学诊断鼻咽癌的比较

目的 通过比较EB病毒抗体检测试剂盒血清学诊断鼻咽癌的准确性和检测结果的一致性,为试剂盒在临床上的使用选择和性能改进提供依据.方法 使用五厂家的EB病毒衣壳抗原IgA和IgG抗体检测试剂盒（VCA IgA和VCA IgG试剂盒）、核抗原I IgA和IgG抗体检测试剂盒（EBNA1 IgA和EBNA1IgG试剂盒）、早期抗原IgA和IgG抗体检测试剂盒（EA IgA和EA IgG试剂盒）以及Zta IgA抗体检测试剂盒,分别检测33例鼻咽癌患者（NPC）、30例健康体检者（HD）和41例非鼻咽癌的其他肿瘤患者（NNPC）血清或血浆样本.结果 A厂家的VCA IgA试剂盒灵敏度高于其他厂家同品种试剂盒,但对于NNPC特异度最低（36.6％）;而D厂家VCA IgA试剂盒的特异度最高（97.6％）,且对HD的特异度均大于90％.B和D厂家的EBNA1 IgA试剂盒间阳性、阴性符合率分别为92.1％和100.0％.A和E厂家的EA IgA试剂盒的灵敏度均较低而特异度高,试剂盒间阳性符合率低（39.4％）,阴性符合率高（98.6％）;而VCA IgG试剂盒的灵敏度高但特异度低.A和C厂家的EBNA1IgG试剂盒的灵敏度高（100.0％,97.0％）但特异度低（3.3％,13.3％）.C厂家EA IgG试剂盒检测所有样本结果均为阴性.结论 五个不同厂家VCA LgA、EA IgA试剂盒诊断鼻咽癌的准确性和检测结果的一致性存在差异,特别是A厂家和其他国内厂家同品种试剂间差异明显,需根据临床目的进行选择.三家国产VCA IgA试剂盒的灵敏度需进一步提高.相反,EBNA IgA试剂盒诊断鼻咽癌的准确性和结果一致性较好.单独使用VCA IgG和EBNA1 IgG试剂盒血清学诊断鼻咽癌的特异度差,其判读界值可能需根据检测且的进行调整.     

EB病毒胸腺嘧啶激酶抗体在鼻咽癌血清学诊断中的作用

目的 建立EB病毒感染和鼻咽癌血清学检测的敏感,特异和有效的方法.方法 以EB病毒早期蛋白胸腺嘧啶激酶为检测抗原,建立ELISA和免疫纤维膜条方法,检测血清中的特异性的IgG抗体.结果 用ELISA和诊断条同时检测了401份血清,其中鼻咽癌患者血清127份.两种方法检测鼻咽癌患者血清抗体均阳性,274份门诊患者血清中,55份ELISA和诊断条检测抗体均阳性,3份诊断条方法检测阳性的血清,ELISA检测A值接近临界值.对胸腺嘧啶激酶的抗体阳性率明显地高于早期蛋白P54.结论 以胸腺嘧啶激酶为检测抗原,为鼻咽癌血清学诊断和高危人群的筛查提供更有效的手段.     

鼻咽癌血清学检测方法的改进

目的 改进现有鼻咽癌血清学早期诊断方法,提高检测灵敏度.方法 用链霉亲和素.生物素放大免疫酶法与既有常规免疫酶法对鼻咽癌防治示范基地所取294份普查血清IgA/VCA,IgA/EA抗体进行血清学检测,并用SPSS统计软件对检测结果进行χ2检验和t检验.结果 共检测30岁以上294份普查人群血清,其中鼻咽癌患者血清106份,健康人血清188份.改进的链霉亲和素一生物素放大免疫酶法与既往已有的免疫酶法相比,血清IgA/VCA、IgA/EA抗体的检测阳性率增加;检测血清抗体的几何平均数明显提高.结论 改进方法可以提高血清学检测的灵敏度,同时保证了检测结果的特异性,提高了鼻咽癌的检出率,可以应用于鼻咽癌早期筛查工作.     

沙鼠IgG兔抗血清的制备及其在IgG抗体检测中的应用

目的用纯化的蒙古沙鼠血清IgG制备相应兔抗血清,并用于幽门螺杆菌（Helicobacter pylori,Hp）疫苗免疫后沙鼠血清中抗原特异性IgG的检测。方法采用饱和硫酸铵沉淀法和Q sepharose high performance阴离子交换层析法纯化蒙古沙鼠血清IgG,免疫日本大白耳兔制备兔抗沙鼠IgG抗血清并进行rProtein A亲和纯化,建立间接ELISA方法用于检测Hp疫苗注射免疫蒙古沙鼠后血清抗原特异性IgG水平。结果以纯化的蒙古沙鼠血清IgG（纯度大于98％）免疫日本大白耳兔获得相应兔抗血清,经亲和层析后其纯度大于90％,回收率约为85％,双扩效价为1：16,ELISA效价为1：320000;ELISA检测结果显示Hp疫苗注射免疫蒙古沙鼠于第2次免疫后产生高水平IgG,第4次免疫后第7天IgG水平达到高峰,随后几周仍然保持高水平。结论所制备的兔抗沙鼠IgG抗体可以用于蒙古沙鼠血清中抗原特异性IgG的检测。     

血清EB病毒抗体水平与鼻咽癌患者预后的关系

目的 探讨血清EB病毒VCA/IgA、EA/IgA、NA1/IgA及Rta/IgG抗体水平与鼻咽癌患者预后的关系.方法 140例初治无远处转移的鼻咽癌患者分别在治疗前和治疗结束后采用免疫酶法检测血清VCA/IgA和EA/IgA,ELISA法检测NA1/IgA和Rta/IgG.随访进行远期疗效和生存的评价.结果 治疗后患者血清VCA/IgA、EA/IgA、NA1/IgA及Rta/IgG抗体水平较治疗前有明显下降,但仍显著高于正常对照组(P＜0.05).治疗后持续缓解的鼻咽癌患者其治疗前VCA/IgA、EA/IgA抗体水平显著低于疾病进展患者(P＜0.05).血清VCA/IgA、EA/IgA、NA1/IgA及Rta/IgG抗体水平与患者的3年总生存率无关(P＞0.05).治疗前VCA/IgA抗体高水平组(≥1∶320)及EA/IgA抗体高水平组(≥1∶80)患者的无进展生存期(61.8％,61.3％)低于抗体低水平组患者(86.5％,86.5％;P＜0.001).Cox回归分析显示治疗前VCA/IgA抗体水平是影响无进展生存的独立危险因素(HR=3.80,P=0.001).结论 VCA/IgA、EA/IgA可为鼻咽癌患者预后判断提供帮助.     

用重组汉坦病毒NP、GP检测急性期HFRS患者血清中特异性IgG、IgM、IgA抗体

目的 探讨肾综合征出血热(HFRS)患者急性期IgA、IgG、IgM抗体的变化规律。方法 使用套式RT-PCR检测此次病毒感染情况。用杆状病毒表达的汉坦病毒重组核蛋白(rNP)和糖蛋白(rGP)为抗原，使用ELISA方法检测了14例急性期肾综合征出血热患者的6l份系列血清中的IgA、IgG、IgM抗体。结果 14例肾综合征出血热患者中，ll例患者的血清用RT-PCR检出家鼠型汉坦病毒核酸。几乎所有肾综合征出血热患者早期即有IgA、IgM、IgG抗体的迅速升高，抗rNP抗体滴度明显高于rGP。3种抗rNP抗体中早期IgG上升趋势最为显著，IgM与IgA次之，IgM与IgA上升趋势相近，但IgA的滴度明显高于IgM。抗rGP抗体中XgA变化最显著，IgG次之。IgM发病2周内总的变化趋势不明显，但是发病l周内滴度上升趋势明显，而发病第2周内则呈下降趋势。其中l例RT-PCR阳性的患者，早期IgM未测出，IgA的滴度却较高。l例重度患者，抗糖蛋白IgG、IgM和IgA抗体滴度均低于其他患者，且整个急性期一直维持较低水平。结论 肾综合征出血热急性期IgA、IgG、lgM变化具有明显的规律，抗糖蛋白和核蛋白抗体病患规律不同，检测IgM的同时检测IgA，可以提高诊断的准确性。     

基于2008分期标准的壮族鼻咽癌各期患者中EB病毒Zta/IgG等抗体阳性率的比较

探讨桂西地区壮族鼻咽癌患者EB病毒EBNA1/IgA、Zta/IgG及Rta/IgG抗体阳性率与鼻咽癌2008分期的关系。收集140例未经治疗的鼻咽癌患者的血清,用酶联免疫吸附法(ELISA)检测EBNA1/IgA、Zta/IgG及Rta/IgG抗体,按"2008分期法"进行分期,分别计算临床分期的各抗体阳性率并进行两两对比,进行统计学分析。鼻咽癌各临床分期组EB-NA1/IgA、Zta/IgG及Rta/IgG抗体阳性率均有统计学差异(P<0.05)。III期的各抗体阳性率明显低于IV期临床分期(P<0.05),Rta/IgG抗体有显著差异(P=0.001)。壮族鼻咽癌患者EB病毒EBNA1/IgA、Zta/IgG及Rta/IgG抗体阳性率与鼻咽癌临床分期有关。或许EBNA1/IgA、Zta/IgG及Rta/IgG抗体对于评估鼻咽癌临床分期有一定的参考价值。     

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.     

Native early antigen of Epstein-Barr virus, a promising antigen for diagnosis of nasopharyngeal carcinoma

The Epstein-Barr virus (EBV) early antigen (EA) complex consists of multiple proteins with relevance for diagnosis of acute, chronic and malignant EBV related diseases, including nasopharyngeal carcinoma (NPC). In a recent study, it was found that the molecular diversity of EBV-specific IgG and IgA antibody responses in NPC patients and demonstrated that these reflect independent B-cell triggering leading to distinct EBV antigen-recognition profiles. The fine-specificity of NPC-related IgG and IgA responses was explored further against defined recombinant and synthetic EBV-EA antigens using immunofluorescence, immunoblot and ELISA techniques and determined their diagnostic value in a large panel of sera from NPC (n = 154), non-NPC tumor patients (n = 133), acute mononucleosis patients (n = 70) and healthy EBV carriers (n = 259). Individual recombinant EBV-EA markers yielded sensitivity/specificity values not exceeding 86%, whereas selected EA-specific peptide epitopes were rather poorly recognized by IgG and IgA antibodies in NPC sera. Surprisingly, we found that a "low salt" native EA-protein extract reproducibly prepared from purified nuclei of EA-induced HH514 cells, and containing characteristic EA(D)-polypeptides, such as p47-54 (BMRF1), p138 (BALF2), p55-DNAse (BGLF5), and p65-TK (BXLF1), but without viral capsid (VCA) or nuclear antigen (EBNA) reactivity, gave highest sensitivity (90.4%) and specificity (95.5%) values for NPC diagnosis in both IgG and IgA ELISA. The data support further the notion that EBV-EA reactive IgG and IgA antibodies in NPC patients are directed against distinct conformational and-in part-linear epitopes on EBV-specific proteins, barely recognized in other EBV-related syndromes. The use of a defined native EBV EA-specific antigen opens the way to further improve serological diagnosis of NPC.     

Analyses of the prognostic significance of the Epstein-Barr virus transactivator ZEBRA protein and diagnostic value of its two synthetic peptides in nasopharyngeal carcinoma.

BACKGROUND: Although numerous serological studies have determined the diagnostic and prognostic values of Epstein-Barr virus (EBV) antibodies in adult patients with nasopharyngeal carcinoma (NPC), little data about the anti-EBV immune response in children with NPC is available. OBJECTIVES: To examine the diagnostic value of IgG antibodies against BamHI Z Epstein-Barr replication activator (ZEBRA) protein and two related synthetic peptides (Zp125 and Zp130). To compare the prognostic value of IgA antibodies against early antigens (EA) and viral capsid antigen (VCA), and IgG antibodies against ZEBRA protein, of Moroccan children treated for NPC with their prognostic value for young and adult NPC patients. STUDY DESIGN: Sera were collected from 255 newly diagnosed Moroccan NPC patients and 226 healthy donors. IgA antibody against VCA and EA was measured by immunofluorescence assays. IgG antibody against ZEBRA, Zp125, and Zp130 was measured by ELISA. RESULTS: No significant difference in the detection of IgG-Zp125 and Zp130 antibodies was observed in children with NPC. IgG-Zp130 were detected less frequently than IgG-Zp125 in young and adult patients, as compared to children. High specificity of IgG-Zp125 and -Zp130 antibodies was found in the three age groups. A decrease in IgG-ZEBRA was observed in patients with NPC in clinical remission, whereas patients with NPC who died or developed metastases maintained or had an increase in these titers. CONCLUSION: IgG-ZEBRA is a better diagnostic and post-therapeutic prognostic marker in children with NPC, who showed very low titers of IgA -VCA and -EA.     

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.     

IgA directed against early antigen of Epstein-Barr virus is no specific marker for the diagnosis of nasopharyngeal carcinoma

The aim of this study was to evaluate the significance and specificity of IgA directed against Epstein-Barr virus (EBV)-specific early antigens (EA) for the unequivocal diagnosis of nasopharyngeal carcinoma (NPC). Therefore, sera from patients with diseases other than NPC, selected on the basis of elevated antibody titres against EBV antigens, were compared to sera from NPC patients with regard to the presence of IgA directed against EBV viral capsid antigen (VCA-IgA) and IgA directed against EA (EA-IgA). Four hundred forty-seven out of 7,508 non-NPC sera tested showed high titres (>512) of IgG directed against Epstein Barr viral capsid antigen (VCA-IgG) and positive VCA-lgA (?32). Two hundred twenty-seven of these sera were compared to 51 VCA-IgA-positive sera from NPC patients regarding the titre of EA-lgA. 60.7% of VCA-lgA-positive NPC sera showed positive EA-lgA, however 33% of VCA-IgA-positive non-NPC patients also exhibited EA-lgA. This result demonstrates that EA-lgA is not specific for NPC and does not allow an unequivocal serological diagnosis of NPC in individual cases. It seems therefore to be of questionable use for screening programs in NPC low-risk areas. The data do not contradict the usefulness of this marker for monitoring of patients treated for NPC and for screening programmes in high-risk areas. © 1994 Wiley-Liss, Inc.     

两阶段EB病毒酶联免疫吸附法筛查鼻咽癌的探讨

目的：采用两阶段EB病毒血清学筛查方法，进行人群鼻咽癌的筛查。方法：用ELISA检测血清EB病毒抗体，首先以EBNAlIgA作为人群鼻咽癌的初筛指标，第二阶段的检查是在EBNAlIgA阳性人群中再进一步检测EBNAlIgG和ZtaIgG两种抗体。结果：EBNAlIgA的灵敏度和特异度分别为91．9％和91．4％，均高于EBNAlIgG和ZtaIgG；第二阶段检查可以将鼻咽癌筛查的特异度提高到96．5％，同时可将人群划分高、中、低三个不同危险层次，其中高危险人群仅占0．39％。结论：实行两阶段筛查法，使鼻咽癌筛查既能达到良好的灵敏度，又能提高检测的特异性，同时还可以将筛查人群划分不同的危险层次。     

Epstein-Barr virus serology in the diagnosis of nasopharyngeal carcinoma

The antibody levels to viral capsid antigen (VCA) and early antigen (EA) of Epstein-Barr virus (EBV) in 164 nasopharyngeal carcinoma (NPC) patients from Sarawak, East Malaysia were significantly higher than those in 147 sex, age and ethnically matched healthy controls. As diagnostic markers of NPC, IgG/VCA at reciprocal titers > or =160 was the most sensitive (89%, with 98% specificity), while IgA/EA at > or =5 was the most specific (100%) but the least sensitive (75%). The sensitivity and specificity of IgA/VCA at reciprocal titers > or =10 were 84% and 97%. IgA/VCA has an advantage over IgG/VCA despite the slightly lower sensitivity due to its consistently more distinct fluorescence reaction. The sensitivity and specificity can be marginally improved by a combination of two tests.     

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.     

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。     

Evaluation of commercial EBV RecombLine assay for diagnosis of nasopharyngeal carcinoma

BACKGROUND: In recent years a number of Epstein-Barr virus (EBV) proteins were defined as being immunodominant for either IgM, IgG or IgA immune responses, yielding promising markers for diagnostic serology. Specific reactivity patterns to these proteins have been described for infectious mononucleosis (IM), nasopharyngeal carcinoma (NPC), various types of lymphoma, and healthy EBV carriers. OBJECTIVES: To compare the NPC-related diagnostic value of EBV RecombLine test (Mikrogen, Germany) with a standardized immunoblot assay [Fachiroh J, Schouten T, Hariwiyanto B, Paramita DK, Harijadi A, Haryana SM, et al. Molecular diversity of Epstein-Barr virus IgG and IgA antibody responses in nasopharyngeal carcinoma: a comparison of Indonesian, Chinese, and European subjects. J Infect Dis 2004;190:53-62] and to define the diagnostic value of individual EBV marker proteins in a population with high incidence of NPC. RESULT: Sera from Indonesian NPC patients taken at primary diagnosis (n=108) were analyzed for IgG and IgA reactivity and compared with regional healthy blood donors (n=62), non-NPC patient controls (n=10) and IM patients (n=10). Most NPC patients and controls showed strong IgG reactivity to VCA-p18, -p23, and EBNA1, limiting their diagnostic use. Few (<20%) healthy donors and patient controls showed IgG reactivity to EA proteins p47/54 and p138, yielding combined sensitivity/specificity and PPV/NPV values of 92.6%/98.3% and 99.0%/88.1%, for diagnosing NPC. NPC sera showed significantly more EBV reactive IgA antibody (>80% positive) than controls (<10% positive), although being less broadly reactive and significantly less strong compared to IgG. For IgA best results were observed for RecombLine EBNA1 with sensitivity/specificity and PPV/NPV values of 92%/89% and 93.4%/85.9%, respectively. CONCLUSION: In high incidence NPC regions with low incidence IM yet high prevalence of EBV infection, both RecombLine IgG and IgA tests provide a useful alternative to the more complex cell-extract based immunoblot assay as confirmation test for NPC diagnosis in particular when using EA and EBNA1 as discriminators in IgG and IgA testing, respectively.