RESUMEN
Multiple sclerosis (MS) is associated with Epstein-Barr virus (EBV) infection, and the antibody response to EBV is reported to be increased in MS. EBV contains multiple antigens, and only a few have been investigated. Our hypothesis is that MS patients will have an increased antibody response to only selected EBV antigens. We used immunoprecipitation and quantitative mass spectrometry to identify candidate EBV antigens. We then measured the antibody response to 10 individual EBV proteins with quantitative ELISA. We found that the antibody response was increased in MS to three of the EBV proteins, but not to the other seven.
Asunto(s)
Anticuerpos Antivirales/sangre , Antígenos Nucleares del Virus de Epstein-Barr/sangre , Herpesvirus Humano 4/metabolismo , Esclerosis Múltiple Recurrente-Remitente/sangre , Adulto , Anticuerpos Antivirales/inmunología , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Femenino , Herpesvirus Humano 4/inmunología , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/inmunologíaRESUMEN
BACKGROUND: Development of indirect enzyme-linked immunosorbent assays (ELISAs) often utilizes synthetic peptides or recombinant proteins from Escherichia coli as immobilized antigens. Because inclusion bodies (IBs) formed during recombinant protein expression in E. coli are commonly thought as misfolded aggregates, only refolded proteins from IBs are used to develop new or in-house diagnostic assays. However, the promising utilities of IBs as nanomaterials and immobilized enzymes as shown in recent studies have led us to explore the potential use of IBs of recombinant Epstein-Barr virus viral capsid antigen p18 (VCA p18) as immobilized antigens in ELISAs for serologic detection of nasopharyngeal carcinoma (NPC). METHODS: Thioredoxin fusion VCA p18 (VCA-Trx) and IBs of VCA p18 without fusion tags (VCA-IBs) were purified from E. coli. The diagnostic performances of IgG/VCA-IBs, IgG/VCA-Denat-IBs (using VCA-IBs coated in 8mol/l urea), IgG/VCA-Trx, and IgG/VCA-Peptide assays were compared by screening 100 NPC case-control pairs. RESULTS: The IgG/VCA-Denat-IBs assay showed the best area under the receiver operating characteristic curve (AUC: 0.802; p<0.05), while the AUCs for the IgG/VCA-IBs, IgG/VCA-Trx, and IgG/VCA-Peptide assays were comparable (AUC: 0.740, 0.727, and 0.741, respectively). CONCLUSION: We improved the diagnostic performance of the ELISA significantly using IBs of recombinant VCA p18.