Epstein-Barr virus nuclear antigen 1 linear epitopes that are reactive with immunoglobulin A (IgA) or IgG in sera from nasopharyngeal carcinoma patients or from healthy donors

Abstract

The entire amino acid sequence of the unique region of the EBNA 1 protein was synthesized as a set of 41 20-residue peptides with an overlap of 10 amino acids. The peptides were tested in the enzyme-linked immunosorbent assay for reactivity with immunoglobulin A (IgA) and IgG in sera from 50 patients with nasopharyngeal carcinoma (NPC) as compared with 36 serum samples from healthy Epstein-Barr virus (EBV)-seropositive donors and 5 serum samples from EBV-negative donors. The most immunoreactive peptide for both IgA and IgG binding was localized to the glycine-alanine repeat domain of the antigen. In the unique regions, 16 immunoreactive peptides were found. Of these, four were reactive with IgG but not IgA and three peptides were reactive with IgA but not IgG in NPC sera. In addition, several IgA and IgG epitopes on the carboxy-terminal region were specifically reactive with NPC sera, but unreactive with sera from healthy EBV-positive donors. The results suggest that EBV serology specific for individual epitopes may provide additional useful information not available by conventional serology with whole antigens or the EBNA complex.

Infectious mononucleosis patients temporarily recognize a unique, cross‐reactive epitope of Epstein‐Barr virus nuclear antigen‐1

“…Interestingly, similar disparities have been directly demonstrated in at least one other EBV-related disorder. Patients with nasopharyngeal carcinoma have been shown to bind different regions of EBNA-1 than normal healthy EBV-positive individuals, including a peptide overlapping slightly with this new infectious mononucleosis epitope [Cheng et al, 1991]. Thus, differential immunological specificity seems to be common to EBVrelated diseases.…”

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

“…In recent years, the molecular basis of EBV serology has been studied in considerable detail, and immunogenic polypeptides have been defined for distinct EBV syndromes [Foong et al, 1990;Ooka et al, 1991;van Grunsven et al, 1993;Gan et al, 1996;Meij et al, 1999Meij et al, , 2002. For NPC serodiagnosis, a number of candidate molecules have been proposed, which can be produced from natural EBV producer cell lines, from recombinant sources or made by peptide synthesis [Cheng et al, 1991;Joab et al, 1991;Littler et al, 1991;Yip et al, 1994;van Grunsven et al, 1994;Gan et al, 1996;Dardari et al, 2000]. An immunoblot method was employed recently to visualize the overall diversity of NPC-related IgG and IgA responses in Chinese, Indonesian, and Caucasian NPC patients [Fachiroh et al, 2004].…”

Immune responses to Epstein–Barr virus lytic proteins in patients with nasopharyngeal carcinoma

“…Some studies showed that NPC patients had slightly higher antibody titers to EBV latent proteins, EBNA1, EBNA2, LMP1, and LMP2, than did normal controls [Seigneurin et al, 1987;Rowe et al, 1988;Cheng et al, 1991;Frsch et al, 1993;Xu et al, 2000]. Furthermore, most NPC patients had significantly higher antibody titers to EBV lytic proteins, such as viral capsid antigen (VCA), Zta, DNase, DNA polymerase, and thymidine kinase (TK) [Henle and Henle, 1979;Cheng et al, 1980;Hadar et al, 1986;Littler et al, 1990;Joab et al, 1991;Littler et al, 1991;Andersson et al, 1994].…”