title: Mature glycoprotein g presents high performance in diagnosing herpes simplex virus type 2 infection in sera of different tanzanian cohorts.
abstract: Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted infection in sub-Saharan Africa. Glycoprotein G (gG) of HSV-2 elicits a type-specific antibody response and is widely used for serodiagnosis. gG is cleaved into a secreted portion (sgG-2) and a highly O-glycosylated mature portion (mgG-2). The performances of these two native immunosorbent purified antigens were compared in an enzyme-linked immunosorbent assay (ELISA) format with a commercially available assay (FOCUS2) using sera from blood donors (n = 194) and individuals (n = 198) with genital ulcer disease (GUD) from Tanzania. Discordant results were resolved by Western blotting. The HSV-2 seroprevalence for blood donors was estimated as 42%, and that for the GUD cohort was estimated as 78%. The prevalence increased significantly with age for both cohorts and was higher among human immunodeficiency virus (HIV)-positive individuals than among HIV-negative subjects. In the GUD cohort with a high HSV-2 prevalence, all three assays showed statistically similar performances, with sensitivities between 97% and 99% and specificities in the range of 86% to 91%. In contrast, among blood donors with a lower seroprevalence, the mgG-2-based ELISA presented significantly higher specificity (97%) than the sgG-2 ELISA (89%) and FOCUS2 (74%). Overall, the mgG-2 ELISA gave a high performance, with negative and positive predictive values of 96% for blood donors and a negative predictive value of 95% and a positive predictive value of 97% for the GUD cohort. We conclude that native purified mgG-2 showed the highest accuracy for detection of HSV-2 in patient sera from Tanzania and is therefore suitable for seroprevalence studies as well as in clinical settings.
authors.affiliation: Department of Virology, University of Göteborg, Guldhedsgatan 10 B, S-413 46 Göteborg, Sweden. staffan.gorander@microbio.gu.se
authors.forename: Staffan
authors.initials: S
authors.lastname: Görander
authors.forename: Judica
authors.initials: J
authors.lastname: Mbwana
authors.forename: Eligius
authors.initials: E
authors.lastname: Lyamuya
authors.forename: Teresa
authors.initials: T
authors.lastname: Lagergård
authors.forename: Jan-Ake
authors.initials: JA
authors.lastname: Liljeqvist
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000818:Animals; D000918:Antibody Specificity; D015153:Blotting, Western / Q000379:methods; D002478:Cells, Cultured; D015331:Cohort Studies; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006558:Herpes Genitalis / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology; D018258:Herpesvirus 2, Human / Q000276:immunology / Q000302:isolation & purification; D006801:Humans; D007239:Infections; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D016036:Seroepidemiologic Studies; D012737:Sex Factors; D013636:Tanzania / Q000453:epidemiology; D014759:Viral Envelope Proteins / Q000145:classification / Q000276:immunology / Q000302:isolation & purification
chemical_list: D014759:Viral Envelope Proteins; C045464:glycoprotein G, herpes simplex virus type 2