title: Detection frequency of human herpesviruses-6A, -6B, and -7 genomic sequences in central nervous system DNA samples from post-mortem individuals with unspecified encephalopathy.
abstract: In this autopsy-based study, human herpesvirus-6 (HHV-6) and -7 (HHV-7) genomic sequence frequency, HHV-6 variants, HHV-6 load and the expression of HHV-6 antigens in brain samples from the individuals, with and without unspecified encephalopathy (controls), using nested and real-time polymerase chain reactions, restriction endonuclease, and immunohistochemical analysis were examined. GraphPad Prism 6.0 Mann-Whitney nonparametric and chi-square test and Fisher's exact test were used for statistical analysis. The encephalopathy diagnoses were shown by magnetic resonance imaging made during their lifetime and macro- and microscopically studied autopsy tissue materials. Widespread HHV-6 and/or HHV-7 positivity was detected in the brain tissue of various individuals with encephalopathy, as well as in controls (51/57, 89.4 % and 35/51, 68.6 %, respectively; p = 0.009). Significantly higher detection frequency of single HHV-6 and concurrent HHV-6 + HHV-7 DNA was found in pia mater meninges, frontal lobe, temporal lobe, and olfactory tract DNAs in individuals with encephalopathy compared to the control group. HHV-6 load and higher frequency of the viral load >10 copies/10(6) cells significantly differed in samples from individuals with and without encephalopathy. The expression of HHV-6 antigens was revealed in different neural cell types with strong predominance in the encephalopathy group. In all HHV-6-positive autopsy samples of individuals with and without encephalopathy, HHV-6B was revealed. Significantly higher detection frequency of beta-herpesvirus DNA, more often detected HHV-6 load >10 copies/10(6) cells, as well as the expression of HHV-6 antigens in different brain tissue samples from individuals with encephalopathy in comparison with control group indicate on potential involvement of these viruses in encephalopathy development.
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia. scapenko@latnet.lv.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Chapenko
authors.affiliation: Study Department, Riga Stradins University, Riga, Latvia.|Pathology Department, Riga 1st Hospital, Riga, Latvia.
authors.forename: Silvija
authors.initials: S
authors.lastname: Roga
authors.affiliation: Institute of Anatomy and Anthropology, Riga Stradins University, Riga, Latvia.
authors.forename: Sandra
authors.initials: S
authors.lastname: Skuja
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia.
authors.forename: Santa
authors.initials: S
authors.lastname: Rasa
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia.
authors.forename: Maksims
authors.initials: M
authors.lastname: Cistjakovs
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia.
authors.forename: Simons
authors.initials: S
authors.lastname: Svirskis
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia.
authors.forename: Zane
authors.initials: Z
authors.lastname: Zaserska
authors.affiliation: Institute of Anatomy and Anthropology, Riga Stradins University, Riga, Latvia.
authors.forename: Valerija
authors.initials: V
authors.lastname: Groma
authors.affiliation: August Kirchenstein Institute of Microbiology and Virology, Riga Stradins University, Ratsupites iela 5, Riga, Latvia.
authors.forename: Modra
authors.initials: M
authors.lastname: Murovska
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001344:Autopsy; D001927:Brain Diseases / Q000175:diagnosis / Q000473:pathology / Q000821:virology*; D016022:Case-Control Studies; D004279:DNA, Viral / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005625:Frontal Lobe / Q000473:pathology / Q000821:virology; D015654:Herpesvirus 6, Human / Q000235:genetics* / Q000378:metabolism; D016199:Herpesvirus 7, Human / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D009474:Neurons / Q000473:pathology / Q000821:virology; D009830:Olfactory Bulb / Q000473:pathology / Q000821:virology; D010841:Pia Mater / Q000473:pathology / Q000821:virology; D019349:Roseolovirus Infections / Q000175:diagnosis / Q000473:pathology / Q000821:virology*; D013702:Temporal Lobe / Q000473:pathology / Q000821:virology; D019562:Viral Load
chemical_list: D004279:DNA, Viral
keywords: Autopsy; Brain tissue; Encephalopathy; Human herpesvirus-6; Human herpesvirus-7