title: Prevalence and cellular reservoir of latent human herpesvirus 6 in tonsillar lymphoid tissue.
abstract: There are few studies that examine prevalence, quantity, and cellular proclivity of latent human herpesvirus 6 (HHV-6) in healthy populations. We examined 69 tonsils with paired blood specimens from children without evidence of acute infection. By polymerase chain reaction (PCR), HHV-6 was detected at low levels in 100% of tonsils and 39% of blood samples (n = 27), suggesting that prevalence of latent HHV-6 infection is high in children and may be underestimated by PCR analysis of blood. Although HHV-6A and HHV-6B were detected, HHV-6B predominated, being found in 97% of samples (n = 67). Tonsil sections from 7 cases were examined by in situ hybridization using 2 HHV-6 probes and immunohistochemical analysis. Using both in situ hybridization and immunohistochemical analysis, all tissues revealed marked HHV-6-specific staining in the squamous epithelium of the tonsillar crypts and rare positive lymphocytes. We conclude that HHV-6 is present universally in tonsils of children, and tonsillar epithelium may be an important viral reservoir in latent infection.
authors.affiliation: Department of Pathology, University of Texas Southwestern Medical Center at Dallas, USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Roush
authors.forename: R K
authors.initials: RK
authors.lastname: Domiati-Saad
authors.forename: L R
authors.initials: LR
authors.lastname: Margraf
authors.forename: K
authors.initials: K
authors.lastname: Krisher
authors.forename: R H
authors.initials: RH
authors.lastname: Scheuermann
authors.forename: B B
authors.initials: BB
authors.lastname: Rogers
authors.forename: D B
authors.initials: DB
authors.lastname: Dawson
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D017931:DNA Primers / Q000737:chemistry; D004279:DNA, Viral / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005077:Exanthema Subitum / Q000473:pathology / Q000821:virology*; D005260:Female; D015654:Herpesvirus 6, Human / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D017403:In Situ Hybridization; D007223:Infant; D008214:Lymphocytes / Q000473:pathology / Q000821:virology; D008297:Male; D014066:Palatine Tonsil / Q000473:pathology / Q000821:virology*; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D004279:DNA, Viral