Novel ELISA for serodiagnosis of nasopharyngeal carcinoma based on a B cell epitope of Epstein‑Barr virus latent membrane protein 2

Abstract

Epstein-Barr virus (EBV) is widespread and is associated with nasopharyngeal carcinoma (NPC). Serological detection of EBV is commonly used for screening, diagnosis and epidemiological surveys of NPC. In the present study, a novel B cell multi-epitope peptide fusion protein (EBV-LMP2-3B), which is composed of three B cell linear epitopes (RIEDPPFNSLL, TLNLT and KSLSSTEFIPN) of EBV latent membrane protein 2 (LMP2), was expressed in a prokaryotic expression system and purified using Ni2+-nitrilotriacetate-Sepharose. The immunogenicity and binding specificity of EBV-LMP2-3B were evaluated on the basis of antibody responses in immunized BALB/c mice, western blotting and indirect immunofluorescence assay. Evaluation of EBV-LMP2-3B as a serological diagnostic reagent was performed using an indirect ELISA in 198 patients with NPC and 102 healthy adults. These results revealed that EBV-LMP2-3B was able to eliminate the high-titer serum antibody response in BALB/c mice. Western blot analysis and indirect immunofluorescence assay confirmed that the mouse immune sera recognized the native LMP2. Compared with healthy adults, patients with NPC demonstrated significantly greater reactivity to EBV-LMP2-3B (P<0.05). Furthermore, it was possible to effectively detect specific IgG in sera from patients with NPC, with a sensitivity of 91.91% and specificity of 93.14%, representing an improvement over the traditional viral capsid antigen-IgA-based detection method with 59.59% sensitivity and 75.49% specificity. In conclusion, the EBV-LMP2-3B protein may be used as a serological diagnostic reagent to screen for and diagnose NPC.

A Promising Tool in Serological Diagnosis: Current Research Progress of Antigenic Epitopes in Infectious Diseases

“…EBV, known as human herpesvirus 4, can lead to many diseases, including infectious mononucleosis, lymphoma, nasopharyngeal carcinoma (NPC), etc. It is a virus commonly susceptible to almost all populations and can cause serious physical damage to patients [ 98 , 99 , 100 ]. As serological testing is available and important for diagnosing EBV infection, as well as usually being targeted by the viral capsid antigen, EBV nuclear antigen and early antigen, the introduction of epitopes will greatly facilitate the development of serological diagnosis.…”

“…Studies have shown that EBV latent membrane protein 2 (LMP2) plays an important role in the pathogenesis of EBV-associated tumors. Therefore, many scientists have focused on the epitope of EBV LMP2, expecting to design a promising screening and diagnostic tool for NPC [ 98 , 102 , 103 ]. Among them, a novel B cell multi-epitope peptide fusion protein (EBV-LMP2-3B) has been constructed, which consists of three linear B cell epitopes of EBV LMP2.…”

“…Among them, a novel B cell multi-epitope peptide fusion protein (EBV-LMP2-3B) has been constructed, which consists of three linear B cell epitopes of EBV LMP2. The sensitivity and specificity of this epitope in the diagnosis of NPC were as high as 91.91% and 93.14%, respectively [ 98 ].…”