Background: identification and discrimination of latent herpes simplex virus (HSV) infection relies on antibody identification. The inclusion of synthetic peptides with HSV glycoproteins provides means for stable and discriminatory assays for population studies.
Objective: to determine whether virus-specific synthetic peptides might identify HSV type 2 (HSV-2) antibodies in the presence of the cross-reactive and more common HSV type 1 (HSV-1) antibodies.
Study design: the capacity of synthetic peptides as HSV antigens was analyzed in enzyme immunoassay (EIA) using well characterized human serum cohorts. The HSV peptide assays were evaluated in comparison with two commercial HSV-2 assays.
Results: a combination of two C-terminal HSV-1 glycoprotein D (gD-1) peptides detected type-common HSV immunoglobulin G (IgG) with high sensitivity (95%) and specificity (93%). Peptides derived from the C-terminus of HSV-2 glycoprotein G (gG-2) had a high HSV-2 type-specificity. Inclusion of both gD-1 and gG-2 peptides gave a sensitivity for human anti-HSV-2 IgG that was similar to that of assays including different amounts of native gG-2. With western blotting as a standard, the sensitivity of the peptide assay ranged between 86% for HSV-2 seropositive persons and 61% for HSV-2 seroconverters. Addition of a small amount of native gG-2 to the peptide assay tended to increase the specificity.
Conclusion: HSV gG and gD peptides show promise as type-specific and type-common HSV antigens. These peptides are more stable and reproducibly prepared than native or recombinant glycoproteins and may be considered for inclusion in future HSV serodiagnostic assays.