Multiplex assays reveal anti-EBV antibody profile and its implication in detection and diagnosis of nasopharyngeal carcinoma.
Epstein-Barr virus (EBV) is detected in nearly 100% of nonkeratinizing nasopharyngeal carcinoma (NPC) and EBV-based biomarkers are used for NPC screening in endemic regions. Immunoglobulin A (IgA) against EBV nuclear antigen 1 (EBNA1) and viral capsid antigen (VCA), and recently identified anti-BNLF2b antibodies have been shown to be the most effective screening tool; however, the screening efficacy still needs to be improved. This study developed a multiplex serological assay by testing IgA and immunoglobulin G (IgG) antibodies against representative EBV antigens that are highly transcribed in NPC and/or function crucially in viral reactivation, including BALFs, BNLF2a/b, LF1, LF2, and Zta (BZLF1). Among them, BNLF2b-IgG had the best performance distinguishing NPC patients from controls (area under the curve: 0.951, 95% confidence interval [CI]: 0.913-0.990). Antibodies to lytic antigens BALF2 and VCA were significantly higher in advanced-stage than in early-stage tumors; in contrast, antibodies to latent protein EBNA1 and early lytic antigen BNLF2b were not correlated with tumor progression. Accordingly, a novel strategy combining EBNA1-IgA and BNLF2b-IgG was proposed and validated improving the integrated discrimination by 15.8% (95% CI: 9.8%-21.7%, p < .0001) compared with the two-antibody method. Furthermore, we found EBV antibody profile in patients was more complicated compared with that in healthy carriers, in which stronger correlations between antibodies against different phases of antigens were observed. Overall, our serological assay indicated that aberrant latent infection of EBV in nasopharyngeal epithelial cells was probably a key step in NPC initiation, while more lytic protein expression might be involved in NPC progression.
Ma L
,Wang TM
,He YQ
,Liao Y
,Yan X
,Yang DW
,Wang RH
,Li FJ
,Jia WH
,Feng L
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Establishment of VCA and EBNA1 IgA-based combination by enzyme-linked immunosorbent assay as preferred screening method for nasopharyngeal carcinoma: a two-stage design with a preliminary performance study and a mass screening in southern China.
A two-stage study was conducted in southern China to determine and validate an optimal combination of Epstein-Barr virus (EBV)-related seromarkers for nasopharyngeal carcinoma (NPC) screening. In the first stage, six seromarkers [VCA-IgA, EA-IgA, Epstein-Barr virus nuclear antigen 1 (EBNA1-IgA), EBNA1-IgG, Zta-IgA and Rta-IgG] were detected by enzyme-linked immunosorbent assay (ELISA) and two traditional NPC screening seromarkers (VCA-IgA and EA-IgA) were detected by immunofluorescence assay (IFA) in serum samples from 191 NPC patients and 337 controls. An optimal combination of seromarkers for NPC diagnosis was selected using logistic regression models. Results showed that the diagnostic performances of VCA-IgA and EA-IgA tested by ELISA were superior to the performances of the same seromarkers by IFA. VCA-IgA combined with EBNA1-IgA by ELISA was identified as the optimal combination, with an area under the receiver operating characteristic (ROC) curve (AUC) up to 0.97, a sensitivity of 95.3% and a specificity of 94.1% for classification of NPCs vs. controls. In the second stage, 5,481 participants aged 30-59 years and without clinical evidence of NPC were recruited into a population-based NPC screening program from May 2008 to February 2009 in Sihui City, China. Their sera were tested simultaneously by both the new and the traditional screening schemes and eight early stage NPC patients were subsequently histopathologically confirmed. The traditional and the new screening schemes had comparable specificity (estimated as 98.5%), but the sensitivity of the new scheme (75.0%) was significantly higher than that of the traditional one (25.0%). The combination of VCA-IgA and EBNA1-IgA by ELISA outperforms the traditional NPC screening scheme and could become the preferred serodiagnostic strategy for NPC screening in high-incidence areas.
Liu Y
,Huang Q
,Liu W
,Liu Q
,Jia W
,Chang E
,Chen F
,Liu Z
,Guo X
,Mo H
,Chen J
,Rao D
,Ye W
,Cao S
,Hong M
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The serological diagnostic value of EBV-related IgA antibody panels for nasopharyngeal carcinoma: a diagnostic test accuracy meta-analysis.
Nasopharyngeal carcinoma (NPC) is diagnosed relatively late and has a poor prognosis, requiring early detection to reduce the disease burden. This diagnostic test accuracy meta-analysis evaluated the serological diagnostic value of nine EBV-related IgA antibody panels (EBNA1-IgA, VCA-IgA, EA-IgA, Zta-IgA, EBNA1-IgA + VCA-IgA, VCA-IgA + EA-IgA, VCA-IgA + Rta-IgG, EBNA1-IgA + VCA-IgA + Zta-IgA and VCA-IgA + EA-IgA + Rta-IgG), aiming to identify suitable serological detection biomarkers for NPC screening.
PubMed, Embase, China National Knowledge Infrastructure and Chinese BioMedical Literature Database were searched from January 1st, 2000 to September 30th, 2023, with keywords nasopharyngeal carcinoma, IgA, screening, early detection, early diagnosis, sensitivity and specificity. Articles on the diagnostic value of serum EBV-related IgA antibody panels for NPC were included. Study selection, data extraction, and quality assessment were performed independently by two researchers, and a third researcher was consulted in the case of disagreement. Bivariate models were used for statistical analysis. The quality of included studies was evaluated through Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2).
A total of 70 articles were included, involving 11 863 NPC cases and 34 995 controls. Among the nine EBV-related IgA antibody panels, EBNA1-IgA + VCA-IgA [0.928 (0.898, 0.950)], VCA-IgA + Rta-IgG [0.925 (0.890, 0.949)], EBNA1-IgA + VCA-IgA + Zta-IgA [0.962 (0.909, 0.985)] and VCA-IgA + EA-IgA + Rta-IgG [0.945 (0.918, 0.964)] demonstrated higher pooled sensitivity (95%CI). In terms of diagnostic odds ratio (DOR) (95%CI), EBNA1-IgA + VCA-IgA [107.647 (61.173, 189.430)], VCA-IgA + Rta-IgG [105.988 (60.118, 186.857)] and EBNA1-IgA + VCA-IgA + Zta-IgA [344.450 (136.351, 870.153)] showed superior performance. Additionally, the SROC curves for EBNA1-IgA + VCA-IgA and VCA-IgA + Rta-IgG were more favorable. However, publication bias was detected for VCA-IgA (P = 0.005) and EBNA1-IgA + VCA-IgA (P = 0.042).
In general, parallel detection of serum EBNA1-IgA, VCA-IgA and Zta-IgA antibodies using ELISA demonstrates better pooled sensitivity and DOR among the studied panels. In the cases where fewer indicators are used, serum VCA-IgA and EBNA1-IgA/Rta-IgG antibody panel exhibits a comparable performance.
The International Prospective Register of Systematic Reviews registration number: CRD42023426984, registered on May 28, 2023.
Liu H
,Lei L
,Song S
,Geng X
,Lin K
,Li N
,Chen W
,Peng J
,Ren J
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《BMC CANCER》