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Skripchenko NV, Gorelik EY, Egorova ES, Vilnits AA, Skripchenko EY, Voitenkov VB, Marchenko NV, Konev AI. [FIRES Syndrome in a Preschool Child]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:132-137. [PMID: 36843470 DOI: 10.17116/jnevro2023123021132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
Severe epileptic syndromes of childhood are an urgent problem for pediatric neurologists and neuroresuscitators. The article presents a clinical observation of FIRES syndrome in a pediatric patient, which is a form of severe drug-resistant epilepsy in children of preschool and school age, the development of which is caused by hyperthermia, probably associated with herpesvirus (human herpesvirus type 6) infection. The features of the progressive course and the difficulties of diagnostic search are reflected. An empirical approach to etiotropic therapy is described, since the disease manifested itself with respiratory manifestations and fever. The tactic of pathogenetic treatment is described, in which drugs of polyfunctional action, such as Cytoflavin, have a priority, many years of experience in the use of which allows the authors to recommend it as a starting intensive therapy.
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Affiliation(s)
- N V Skripchenko
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia.,Saint-Petersburg State Pediatric Medical University, St. Petersburg, Russia
| | - E Y Gorelik
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia
| | - E S Egorova
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia
| | - A A Vilnits
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia.,Saint-Petersburg State Pediatric Medical University, St. Petersburg, Russia
| | - E Y Skripchenko
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia.,Saint-Petersburg State Pediatric Medical University, St. Petersburg, Russia
| | - V B Voitenkov
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia
| | - N V Marchenko
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia
| | - A I Konev
- Pediatric Research and Clinical Center for Infectious Diseases, St. Petersburg, Russia.,Saint-Petersburg State Pediatric Medical University, St. Petersburg, Russia
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2
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Kasimir F, Toomey D, Liu Z, Kaiping AC, Ariza ME, Prusty BK. Tissue specific signature of HHV-6 infection in ME/CFS. Front Mol Biosci 2022; 9:1044964. [PMID: 36589231 PMCID: PMC9795011 DOI: 10.3389/fmolb.2022.1044964] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/05/2022] [Indexed: 12/15/2022] Open
Abstract
First exposure to various human herpesviruses (HHVs) including HHV-6, HCMV and EBV does not cause a life-threatening disease. In fact, most individuals are frequently unaware of their first exposure to such pathogens. These herpesviruses acquire lifelong latency in the human body where they show minimal genomic activity required for their survival. We hypothesized that it is not the latency itself but a timely, regionally restricted viral reactivation in a sub-set of host cells that plays a key role in disease development. HHV-6 (HHV-6A and HHV-6B) and HHV-7 are unique HHVs that acquire latency by integration of the viral genome into sub-telomeric region of human chromosomes. HHV-6 reactivation has been linked to Alzheimer's Disease, Chronic Fatigue Syndrome, and many other diseases. However, lack of viral activity in commonly tested biological materials including blood or serum strongly suggests tissue specific localization of active HHV-6 genome. Here in this paper, we attempted to analyze active HHV-6 transcripts in postmortem tissue biopsies from a small cohort of ME/CFS patients and matched controls by fluorescence in situ hybridization using a probe against HHV-6 microRNA (miRNA), miR-aU14. Our results show abundant viral miRNA in various regions of the human brain and associated neuronal tissues including the spinal cord that is only detected in ME/CFS patients and not in controls. Our findings provide evidence of tissue-specific active HHV-6 and EBV infection in ME/CFS, which along with recent work demonstrating a possible relationship between herpesvirus infection and ME/CFS, provide grounds for renewed discussion on the role of herpesviruses in ME/CFS.
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Affiliation(s)
- Francesca Kasimir
- Institute for Virology and Immunobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Danny Toomey
- HHV-6 Foundation, Santa Barbara, CA, United States
| | - Zheng Liu
- Institute for Virology and Immunobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Agnes C. Kaiping
- Institute for Virology and Immunobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany
| | - Maria Eugenia Ariza
- Department of Cancer Biology and Genetics (CBG), Institute for Behavioral Medicine Research (IBMR), The Ohio State University, Columbus, OH, United States
| | - Bhupesh K. Prusty
- Institute for Virology and Immunobiology, Julius-Maximilians-University of Würzburg, Würzburg, Germany,*Correspondence: Bhupesh K. Prusty,
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3
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Wang JQ, Yang HY, Shao X, Jiang XY, Li JM. Latent, Early or Late Human Herpes Virus-6B Expression in Adult Mesial Temporal Lobe Epilepsy: Association of Virus Life Cycle with Inflammatory Cytokines in Brain Tissue and Cerebral Spinal Fluid. Neuroscience 2022; 504:21-32. [PMID: 36067950 DOI: 10.1016/j.neuroscience.2022.08.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/08/2022] [Accepted: 08/25/2022] [Indexed: 10/31/2022]
Abstract
BACKGROUND Human herpes virus-6B (HHV-6B) was suggested as an important etiologic factor of mesial temporal lobe epilepsy, while the mechanism is still unknown. Here, we aimed to analyze antigens representing latent, early and late HHV-6B infection and the association with inflammatory cytokines in brain tissue and cerebral spinal fluid (CSF) from MTLE patients with HHV-6B-positivity. METHODS Nested polymerase chain reaction (nPCR), real-time PCR, immunohistochemistry (ICH) and suspension bead array for cytokines were performed. RESULTS Nested polymerase chain reaction (nPCR) in brain tissue revealed HHV-6B DNA in 19 of 49 MTLE patients (39%) and 1 of 19 controls (5%) (P < 0.001), but not in CSF. ICH showed HHV-6B early antigen (P41) positivity in 3 patients (6%), late antigen (gp116/54/64) positivity in 5 patients (10%), latent antigen (U94) positivity in 8 patients (16%), and multiple antigen (early and late or/and latent) positivity in 9 patients (18%). None of these HHV-6B related proteins were found positive in control brain tissue. PCR revealed significant up-regulation of IL-1a, IL-2 and IL-7 mRNA levels in the brain tissue from MTLE patients expressing early antigens compared to those expressing late, latent, multiple antigens, negative antigens and the controls. Suspension bead array of the CSF confirmed significant up-regulation of IL-1a and IL-7 protein expression from MTLE patients expressing early antigens compared to the other groups. CONCLUSIONS Our finding suggests HHV-6B is a common etiologic agent of MTLE. Different virus life cycle may play an important modifying role in inflammatory biology that warrants further investigation. Though virus DNA is difficult detected in CSF, up-regulation of IL-1a and IL-7 in CSF indicates the two cytokines may be taken as indirect biomarker of HHV-6B infection.
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Affiliation(s)
- Jia-Qi Wang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Hong-Yu Yang
- University of Electronic Science and Technology of China Hospital, China
| | | | - Xin-Yue Jiang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China; Chengdu Second People's Hospital, Chengdu, Sichuan Province, China
| | - Jin-Mei Li
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
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4
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Kawamura Y, Maesawa S, Numoto S, Saito R, Yoshikawa T, Okumura A. Human herpesvirus 6 DNA was not detected in a brain specimen from a patient with mesial temporal sclerosis after status epilepticus due to human herpesvirus 6 infection. Epilepsia Open 2022; 7:817-821. [PMID: 35916714 PMCID: PMC9712467 DOI: 10.1002/epi4.12634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/28/2022] [Indexed: 12/30/2022] Open
Abstract
We performed virological analysis of resected brain tissues from a patient with temporal lobe epilepsy associated with mesial temporal sclerosis after febrile status epilepticus caused by human herpesvirus 6 infection. The patient had febrile status epilepticus at 9 months of age associated with human herpesvirus 6 infection. Magnetic resonance imaging revealed reduced water diffusion in the right temporal lobe and hippocampus. Polymerase chain reaction analysis detected 1.6 × 105 copies/μg of human herpesvirus 6 DNA in whole blood, but none in the cerebrospinal fluid. The patient developed temporal lobe epilepsy associated with mesial temporal sclerosis at 67 months of age, necessitating surgical treatment. Anterior temporal lobectomy was performed at 171 months of age. Real-time polymerase chain reaction analysis of resected brain tissues revealed no viral DNA. In our patient, human herpesvirus 6 infection triggered febrile status epilepticus, while direct evidence to prove contribution of HHV-6 to the development of MTS was not obtained.
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Affiliation(s)
- Yoshiki Kawamura
- Department of PediatricsFujita Health University School of MedicineAichiJapan
| | - Satoshi Maesawa
- Department of NeurosurgeryNagoya University Graduate School of MedicineAichiJapan
| | - Shingo Numoto
- Department of PediatricsAichi Medical UniversityAichiJapan
| | - Ryuta Saito
- Department of NeurosurgeryNagoya University Graduate School of MedicineAichiJapan
| | - Tetsushi Yoshikawa
- Department of PediatricsFujita Health University School of MedicineAichiJapan
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5
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Tong J, Zou Q, Wang S, Liu J, Chen R, Chen Y, Zhao W, Ma L, Li Q. Human herpesvirus 6B infection in mesial temporal lobe epilepsy: a meta-analysis. ACTA EPILEPTOLOGICA 2022. [DOI: 10.1186/s42494-022-00083-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Whether human herpesvirus 6B (HHV-6B) can affect mesial temporal lobe epilepsy (MTLE) remains controversial. The present meta-analysis was aimed to evaluate whether HHV-6B is significantly associated with MTLE.
Methods
Six studies were included in this meta-analysis, comprising 183 MTLE patients and 75 controls. In these studies, HHV-6B infection in astrocytes and brain samples of MTLE patients and controls was investigated by polymerase chain reaction and immunofluorescence.
Results
The frequency of HHV-6B infection detection is significantly higher in the MTLE group than in the control group (OR = 9.42, 95%CI: 3.66–24.25), P < 0.00001). Although febrile convulsion is strongly associated with MTLE, the formation of febrile convulsion leading to MTLE is not associated with HHV-6B infection (OR = 2.68, 95%CI: 0.93–7.73), P = 0.07). Moreover, the HHV-6B-specific antigen is co-localized to cells positive for GFAP that morphologically resemble astrocytes. HHV-6B mainly infects astrocytes, oligodendrocytes and microglia, and could damage the vascular endothelial cells of the central nervous system.
Conclusions
There is an association between HHV-6B infection and MTLE. Future large-scale, multi-center, controlled, prospective studies are required to confirm these findings. In addition, the exact mechanism underlying the effects of HHV-6B infection on MTLE needs to be further investigated.
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6
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Theodore WH, Leibovitch E, Billioux BJ, Inati SK, Zaghloul K, Heiss J, Gaillard WD, Jacobson S. Human herpesvirus 6 and epilepsy. Epilepsia Open 2021; 6:777-780. [PMID: 34324277 PMCID: PMC8633468 DOI: 10.1002/epi4.12531] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 01/12/2023] Open
Abstract
We investigated the association between human herpesvirus 6 (HHV‐6) and mesial temporal sclerosis (MTS) in 87 patients who had surgery for drug‐resistant epilepsy. Fifty‐four had MTS, 22 focal cortical dysplasia (FCD), four tumors, three vascular malformations, and three a history of encephalitis. We extracted DNA from fresh brain tissue immediately after surgery and performed viral detection with quantitative real‐time polymerase chain reaction (PCR) or digital droplet PCR specific for HHV‐6A and HHV‐6B. Tissue was studied with standard clinical techniques, including hematoxylin and eosin, glial fibrillary acidic protein, and NeuN stains. Twenty‐nine of 54 patients with MTS, six of 23 with focal cortical dysplasia (FCD), and one of three with a history of encephalitis were positive for HHV‐6 (P < .02). Febrile seizure history was not associated with HHV‐6 detection. Patients with MTS had significantly lower seizure onset age than those with other pathologies. Thirteen patients had positron emission tomography with [11C]PBR28, a marker for reactive astrocytes and activated microglia; there was a trend for HHV‐6‐positive patients to have higher binding in their seizure foci, suggesting inflammation. Our study supports a potential role for HHV‐6 in the etiology of MTS.
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Affiliation(s)
- William H Theodore
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Emily Leibovitch
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Bridgette J Billioux
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Sara K Inati
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - Kareem Zaghloul
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - John Heiss
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
| | - William D Gaillard
- Department of Neurology, Children's National Medical Center, Washington, DC, USA
| | - Steven Jacobson
- Division of Intramural Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD, USA
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7
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Abstract
AbstractHuman herpes virus 6 (HHV-6) is a ubiquitous and most common pathogen that affects humans. Human herpes virus 6B (HHV-6B) is a wide spread human herpesvirus that infects most people when they are children, establishes latent infections in the central nervous system (CNS), especially in the hippocampus and amygdala, and induces neurologic diseases. HHV-6 can establish a latent infection and be reactivated by various stimuli. Recently, viral genomic DNA of HHV-6B has been detected in surgically removed brain tissues of intractable epilepsy patients, suggesting the involvement of HHV-6B in the pathogenesis of epilepsy. Temporal lobe epilepsy (TLE) has been shown to be closely related with HHV-6B. TLE patients with HHV-6B in their brains suffer from reiterative attacks of febrile seizures and hippocampal sclerosis. However, the mechanisms underlying the contribution of this virus to the development of TLE remains unknown. The direct damage and immune activation caused by the virus are involved in the process of neuron damage, abnormal neural circuit formation and glial cell proliferation. In addition, some cytokines like interleukin-17A (IL-17A), nuclear factor-kappa B (NF-κb), transforming growth factor-β (TGF-β), mitogen-activated protein kinase (MAPK) and phospholipase A2 are up-regulated and involved in the pathological process of TLE. More studies are needed to clarify the mechanisms underlying the link between HHV-6B and epilepsy, and identify biomarkers to recognize different patient groups for anti-inflammatory or immunomodulatory therapies.
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8
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Komaroff AL, Pellett PE, Jacobson S. Human Herpesviruses 6A and 6B in Brain Diseases: Association versus Causation. Clin Microbiol Rev 2020; 34:e00143-20. [PMID: 33177186 PMCID: PMC7667666 DOI: 10.1128/cmr.00143-20] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Human herpesvirus 6A (HHV-6A) and human herpesvirus 6B (HHV-6B), collectively termed HHV-6A/B, are neurotropic viruses that permanently infect most humans from an early age. Although most people infected with these viruses appear to suffer no ill effects, the viruses are a well-established cause of encephalitis in immunocompromised patients. In this review, we summarize the evidence that the viruses may also be one trigger for febrile seizures (including febrile status epilepticus) in immunocompetent infants and children, mesial temporal lobe epilepsy, multiple sclerosis (MS), and, possibly, Alzheimer's disease. We propose criteria for linking ubiquitous infectious agents capable of producing lifelong infection to any neurologic disease, and then we examine to what extent these criteria have been met for these viruses and these diseases.
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Affiliation(s)
- Anthony L Komaroff
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Philip E Pellett
- Department of Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Steven Jacobson
- Virology/Immunology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
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9
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Santpere G, Telford M, Andrés-Benito P, Navarro A, Ferrer I. The Presence of Human Herpesvirus 6 in the Brain in Health and Disease. Biomolecules 2020; 10:biom10111520. [PMID: 33172107 PMCID: PMC7694807 DOI: 10.3390/biom10111520] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 01/03/2023] Open
Abstract
The human herpesvirus 6 (HHV-6) -A and -B are two dsDNA beta-herpesviruses infectingalmost the entire worldwide population. These viruses have been implicated in multipleneurological conditions in individuals of various ages and immunological status, includingencephalitis, epilepsy, and febrile seizures. HHV-6s have also been suggested as playing a role inthe etiology of neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease. Theapparent robustness of these suggested associations is contingent on the accuracy of HHV-6detection in the nervous system. The effort of more than three decades of researching HHV-6 in thebrain has yielded numerous observations, albeit using variable technical approaches in terms oftissue preservation, detection techniques, sample sizes, brain regions, and comorbidities. In thisreview, we aimed to summarize current knowledge about the entry routes and direct presence ofHHV-6 in the brain parenchyma at the level of DNA, RNA, proteins, and specific cell types, inhealthy subjects and in those with neurological conditions. We also discuss recent findings relatedto the presence of HHV-6 in the brains of patients with Alzheimer's disease in light of availableevidence.
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Affiliation(s)
- Gabriel Santpere
- Neurogenomics Group, Research Programme on Biomedical Informatics (GRIB), Hospital del Mar Medical Research Institute (IMIM), DCEXS, Universitat Pompeu Fabra, 08003 Barcelona, Catalonia, Spain
- Correspondence: (G.S.); (I.F.)
| | - Marco Telford
- Institute of Evolutionary Biology (UPF-CSIC), Departament de Ciències Experimentals i la Salut, Universitat Pompeu Fabra, PRBB, 08003 Barcelona, Catalonia, Spain; (M.T.); (A.N.)
| | - Pol Andrés-Benito
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain;
| | - Arcadi Navarro
- Institute of Evolutionary Biology (UPF-CSIC), Departament de Ciències Experimentals i la Salut, Universitat Pompeu Fabra, PRBB, 08003 Barcelona, Catalonia, Spain; (M.T.); (A.N.)
- Catalan Institution of Research and Advanced Studies (ICREA), Passeig de Lluís Companys 23, 08010 Barcelona, Spain
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Carrer del Dr. Aiguader 88, 08003 Barcelona, Spain
- Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Wellington 30, 08005 Barcelona, Spain
| | - Isidre Ferrer
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain;
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Hospitalet de Llobregat, 08907 Barcelona, Spain
- Bellvitge University Hospital, IDIBELL (Bellvitge Biomedical Research Centre), Hospitalet de Llobregat, 08908 Barcelona, Spain
- Correspondence: (G.S.); (I.F.)
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10
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Dunn N, Kharlamova N, Fogdell-Hahn A. The role of herpesvirus 6A and 6B in multiple sclerosis and epilepsy. Scand J Immunol 2020; 92:e12984. [PMID: 33037649 PMCID: PMC7757173 DOI: 10.1111/sji.12984] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/11/2020] [Accepted: 10/05/2020] [Indexed: 01/07/2023]
Abstract
Human herpesvirus 6A (HHV‐6A) and 6B (HHV‐6B) are two closely related viruses that can infect cells of the central nervous system (CNS). The similarities between these viruses have made it difficult to separate them on serological level. The broad term HHV‐6 remains when referring to studies where the two species were not distinguished, and as such, the seroprevalence is over 90% in the adult population. HHV‐6B has been detected in up to 100% of infants with the primary infection roseola infantum, but less is known about the primary infection of HHV‐6A. Both viruses are neurotropic and have capacity to establish lifelong latency in cells of the central nervous system, with potential to reactivate and cause complications later in life. HHV‐6A infection has been associated with an increased risk of multiple sclerosis (MS), whereas HHV‐6B is indicated to be involved in pathogenesis of epilepsy. These two associations show how neurological diseases might be caused by viral infections, but as suggested here, through completely different molecular mechanisms, in an autoimmune disease, such as MS, by triggering an overreaction of the immune system and in epilepsy by hampering internal cellular functions when the immune system fails to eliminate the virus. Understanding the viral mechanisms of primary infection and reactivation and their spectrum of associated symptoms will aid our ability to diagnose, treat and prevent these severe and chronic diseases. This review explores the role of HHV‐6A and HHV‐6B specifically in MS and epilepsy, the evidence to date and the future directions of this field.
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Affiliation(s)
- Nicky Dunn
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Center for Molecular Medicine, Stockholm, Sweden
| | - Nastya Kharlamova
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Center for Molecular Medicine, Stockholm, Sweden
| | - Anna Fogdell-Hahn
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Center for Molecular Medicine, Stockholm, Sweden
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11
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Akinsoji EO, Leibovitch E, Billioux BJ, Abath Neto OL, Ray-Chaudhury A, Inati SK, Zaghloul K, Heiss J, Jacobson S, Theodore WH. HHV-6 and hippocampal volume in patients with mesial temporal sclerosis. Ann Clin Transl Neurol 2020; 7:1674-1680. [PMID: 33325656 PMCID: PMC7480901 DOI: 10.1002/acn3.51152] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 07/16/2020] [Indexed: 12/11/2022] Open
Abstract
Objective To study the effects of human herpes virus 6 (HHV‐6) on the hippocampal volume in patients with mesial temporal sclerosis (MTS). Background HHV‐6 may play an etiologic role in MTS. Previous studies found a possible association with febrile status epilepticus. Several investigators have reported a higher prevalence of HHV‐6 in MTS resections compared to other epilepsy etiologies. Design/Methods We used FreeSurfer to segment cortical structures and obtain whole hippocampal and subfield volumes in 41 patients with intractable epilepsy. In addition, an investigator blinded to other data traced hippocampi manually on each slice. The main study outcome measure was the asymmetry index (AI) between hippocampal volumes ipsilateral and contralateral to seizure foci compared between HHV‐6 positive and negative patients. Viral DNA was isolated from fresh brain tissue obtained at temporal lobectomy. For 25 patients, viral detection was performed using quantitative real‐time PCR specific for HHV‐6A and HHV‐6B. For 16 patients, viral DNA detection was performed using digital droplet PCR specific for HHV‐6A and HHV‐6B. Results Twenty‐two patients were positive (14 of 25 tested with real‐time PCR, and 8 of 16 with digital droplet PCR), and 19 negatives for HHV‐6. HHV‐6 negative patients had significantly greater AI and lower total hippocampal volume ipsilateral to seizure foci than HHV‐6 positive patients. Epilepsy duration and age of onset did not affect results. Interpretation Our data suggest multiple potential etiologies for MTS. HHV‐6 may have a less severe effect on the hippocampus than other etiologies.
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Affiliation(s)
- Elizabeth O Akinsoji
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - Emily Leibovitch
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - B Jeanne Billioux
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - Osorio Lopes Abath Neto
- National Institute of Neurological Disorders and Stroke, National Cancer Institute, NIH, Bethesda, Maryland
| | - Abhik Ray-Chaudhury
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - Sara K Inati
- EEG Laboratory, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - Kareem Zaghloul
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - John Heiss
- Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - Steven Jacobson
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
| | - William H Theodore
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland
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12
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HHV-6-Associated Neurological Disease in Children: Epidemiologic, Clinical, Diagnostic, and Treatment Considerations. Pediatr Neurol 2020; 105:10-20. [PMID: 31932119 DOI: 10.1016/j.pediatrneurol.2019.10.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 10/12/2019] [Accepted: 10/17/2019] [Indexed: 02/04/2023]
Abstract
Human herpesviruses 6A and 6B, often referred to collectively as human herpesvirus 6, are a pair of beta-herpesviruses known to cause a variety of clinical syndromes in both immunocompetent and immunocompromised individuals. Most humans are infected with human herpesvirus 6B, and many with human herpesvirus 6A. Primary infection typically occurs in early childhood, although large-scale reviews on the topic are limited. Herein, the authors explore the clinical manifestations of human herpesvirus 6-associated disease in both immunocompetent and immunocompromised pediatric patients, the risk factors for development of human herpesvirus 6-associated neurological disease, the risk of autoimmunity associated with development of active or latent infection, the relevance of human herpesvirus 6-specific diagnostic tests, and the medications used to treat human herpesvirus 6. The goal of this review is to improve the current understanding of human herpesvirus 6 in pediatric populations and to examine the most effective diagnostic and therapeutic interventions in this disease state.
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13
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Abstract
PURPOSE Human herpesvirus 6 (HHV-6) can infect the central nervous system in immunocompromised individuals. Less is known, however, about HHV-6 infection in immunocompetent patients. This study evaluated the neurologic features and prognosis of HHV-6 infection in immunocompetent patients. METHODS The medical records of patients aged 1 month to 18 years who underwent cerebrospinal fluid examinations and were tested for 6 viruses, including HHV-6, by multiplex polymerase chain reaction were evaluated retrospectively. RESULTS During the study period, 252 children were included. None had underlying disease and all were immunocompetent. Their mean age at diagnosis was 40.98 ± 47.65 months. Of these 252 patients, 144 (57.1%) were diagnosed with meningitis, 84 (33.3%) with febrile seizure not induced by meningitis, and 24 (9.5%) with encephalitis. Of the 9 patients positive for HHV-6, 3 (33.3%) had encephalitis, 3 (33.3%) had meningitis, 1 (11.1%) had complex febrile seizure, and the other 2 patients had fever alone. Outcomes were worse in the seizure group (Fisher exact test, P = .048), especially in patients with status epilepticus (Fisher exact test, P = .012), than in the other groups. Encephalitis patients with and without HHV-6 differed significantly in age (24.0 ± 10.8 vs 63.4 ± 47.7 months, t-test P < .05), with status epilepticus being more frequent in those with HHV-6 (Fisher exact test, P = .010). All 3 encephalitis patients positive for HHV-6 had neurologic sequelae; 2 who had mild sequelae were treated with antiviral agents and intravenous immunoglobulin. CONCLUSIONS HHV-6 may not be completely benign in immunocompetent children. It can be associated with encephalitis and poor prognosis.
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Affiliation(s)
- Su Jeong You
- Department of Pediatrics, Inje University Sanggye Paik Hospital, Seoul, Korea
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14
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Biganzoli P, Frutos MC, Venezuela F, Mosmann J, Kiguen A, Pavan J, Ferreyra L, Cuffini C. Detection of human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7) DNA in endocervical samples from a positive and negative HPV woman of Córdoba, Argentina. J Clin Pathol 2019; 73:30-34. [PMID: 31315894 DOI: 10.1136/jclinpath-2019-205795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 06/24/2019] [Accepted: 06/28/2019] [Indexed: 11/03/2022]
Abstract
AIMS The purpose of the present study was to elucidate the presence of human herpesvirus 6A (HHV-6A), HHV-6B and HHV-7 in samples of the uterine cervix through detection of viral DNA. We analysed normal tissues, samples with low-grade squamous intraepithelial lesions (LSILs) and high-grade squamous intraepithelial lesions (HSILs). We correlated the presence of HHV-6 and HHV-7 with the finding of human papillomavirus (HPV) in mucosal samples. METHODS Cervical samples were examined and grouped as follows: group 1 (n=29), normal cytology; group 2 (n=61), samples with LSIL; group 3 (n=35), samples with HSIL. Molecular biology examinations were performed in all samples to detect HHV-6, HHV-7 and HPV DNA and to typify HHV-6 species. RESULTS Group 1: normal cytology and HPV (-): HHV-6: 6.8% (2/29), HHV-7: 79.3% (23/29); group 2: LSIL and HPV (-): HHV-6: 93.1% (27/29), HHV-7: 96.5% (28/29); LSIL and HPV (+): HHV-6: 0% (0/32), HHV-7: 90.6% (29/32); group 3: HSIL and HPV (-): HHV-6: 20% (2/10), HHV-7: 70% (7/10); HSIL HPV (+): HHV-6: 12% (3/25), HHV-7: 68% (17/25). HHV-6A DNA was not detected in any samples. CONCLUSIONS (1) Both HHV-6 and HHV-7 infect the mucosal cells of the cervix with higher prevalence of HHV-7. (2) The higher prevalence of HHV-6 in LSIL HPV (-) samples compared with those with normal cytology indicates that it constitutes a possible risk factor for atypia production. (3) The presence of HHV-7 in all samples questions its role in the production of atypia. (4) The finding of HHV-6 and HHV-7 suggests that the cervical mucosa is a possible transmission pathway for these viruses.
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Affiliation(s)
- Patricia Biganzoli
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina .,Medical Bacteriology and Virology, School of Medical Sciences, National University of Córdoba, Córdoba, Argentina
| | - María Celia Frutos
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina
| | - Fernando Venezuela
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina
| | - Jessica Mosmann
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina
| | - Ana Kiguen
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina
| | - Jorge Pavan
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina.,Medical Bacteriology and Virology, School of Medical Sciences, National University of Córdoba, Córdoba, Argentina
| | - Leonardo Ferreyra
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina.,Medical Bacteriology and Virology, School of Medical Sciences, National University of Córdoba, Córdoba, Argentina
| | - Cecilia Cuffini
- Virology Institute 'Dr. J. Vanella', School of Medical Sciences, National University of Córdoba, Cordoba, Cordoba, Argentina
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15
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Bartolini L, Theodore WH, Jacobson S, Gaillard WD. Infection with HHV-6 and its role in epilepsy. Epilepsy Res 2019; 153:34-39. [DOI: 10.1016/j.eplepsyres.2019.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 03/18/2019] [Accepted: 03/24/2019] [Indexed: 01/09/2023]
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16
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Abd El Motteleb DM, Hussein S, Hasan MM, Mosaad H. Comparison between the effect of human Wharton's jelly-derived mesenchymal stem cells and levetiracetam on brain infarcts in rats. J Cell Biochem 2018; 119:9790-9800. [PMID: 30171723 DOI: 10.1002/jcb.27297] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 06/26/2018] [Indexed: 01/29/2023]
Abstract
BACKGROUND Stroke represents one of the major causes of death worldwide. Neuroprotection remains an important goal of stroke therapy. Stem cell therapeutic effect is attributed to the neuroprotective effect and the regulation of the oxidant stress. Levetiracetam (LEV), a second-generation antiepileptic drug, was reported to confer neuronal protection after cerebral ischemia reperfusion. AIM To investigate the effect of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) and LEV on the size of brain infarcts, the histological structure, the neurotrophic, and the antioxidant gene expression in middle cerebral artery occlusion in rats. METHOD The rats were divided into five equal groups of 12 rats each as follows. Sham control group: received phosphate-buffered saline (PBS); ischemia/reperfusion (I/R) group: received PBS before ligation; stem cell-treated group: the animal received MSCs before ligation; LEV-treated group: the animal received LEV before occlusion; combined group: the animals received both MSCs and LEV before occlusion. Hematoxylin and eosin staining was performed to study the histological structure of the brain. Real-time polymerase chain reaction (RT-PCR) was performed to assess gene expression. RESULTS Both MSCs and LEV improved memory and learning in the treated groups compared with I/R group. Significant reduction of the infarct size in WJ-MSC- or LEV-treated groups when compared with untreated ones was found. By RT-PCR, a significant decrease of the expression values of glial-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), phosphatidylethanolamine binding protein 1 (PEBP1), and copper-zinc SOD (Cu/ZnSOD) genes and a significant increase of pro-oxidant iNOS gene in the I/R rats compared with the sham group was detected. There was a significant increase in the expression values of GDNF, BDNF, PEBP1, and Cu/ZnSOD genes in both treated groups when compared with the I/R group. Rats treated with WJ-MSCs showed better results than rats treated with LEV. Finally, the combined use of LEV and WJ-MSCs was the most effective regimen as regard infarction volume and functional learning and memory tests. CONCLUSION In the brain ischemia model, combined WJ-MSCs and LEV have demonstrated striking protective effects in brain infarction by the modulation of the oxidant status and neuroprotective effect.
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Affiliation(s)
| | - Samia Hussein
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Mai M Hasan
- Medical Physiology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Hala Mosaad
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
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17
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Engdahl E, Niehusmann P, Fogdell-Hahn A. The effect of human herpesvirus 6B infection on the MAPK pathway. Virus Res 2018; 256:134-141. [PMID: 30130603 DOI: 10.1016/j.virusres.2018.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 08/03/2018] [Accepted: 08/16/2018] [Indexed: 12/24/2022]
Abstract
BACKGROUND Human herpesvirus 6B (HHV-6B) is a neurotropic virus that has been repeatedly associated with mesial temporal lobe epilepsy (MTLE). However, the mechanism behind this suggested association is not known. Therefore, the aim of this study was to investigate what genes were affected by HHV-6B, possibly revealing HHV-6B induced disease causing mechanisms. MATERIAL AND METHOD First, gene expression in MTLE tissue positive for HHV-6B DNA (n = 10) and negative for HHV-6B DNA (n = 14) was compared using the Affymetrix® Human Gene 2.1 ST Array. Secondly, in vitro experiments were conducted where Molt-3 T cells were infected with HHV-6B and gene expression of MAP2K4 (MKK4) and 89 other genes in the MAPK signaling pathway was investigated using qPCR. In addition, phosphorylated MKK4 was assessed using IFA and the DNA methylation investigated with Illumina Infinium HumanMethylation450 BeadChip array. RESULTS MAP2K4 was one of the most differently expressed genes in the Affymetrix array, suggesting an upregulation by HHV-6B infection in MTLE tissue. No gene reached statistical significance but MAP2K4 was selected for further investigation in vitro, where it was clearly upregulated by HHV-6B infection both on gene expression and protein expression level. Further investigating expression of genes in the MAPK pathways in vitro revealed that several genes were affected by HHV-6B infection, but none of these genes displayed viral induced changes in DNA methylation. CONCLUSIONS As the MAPK pathways are involved in transforming different stimuli (like stress) into a cellular responses (like apoptosis or inflammation), it may not be surprising that genes in these pathways are affected by virus infection. This is the first report of HHV-6B's effect on these signaling cascades and given that both dysregulation of the MAPK pathways and an association with HHV-6B have been previously observed in epilepsy, a possible link of infection induced dysregulation of MAPK in epilepsy warrant further investigation.
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Affiliation(s)
- Elin Engdahl
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Pitt Niehusmann
- Department of Neurology/Pathology, Oslo University Hospital, 0450, Oslo, Norway; Department of Neuropathology, University of Bonn Medical Center, 53113, Bonn, Germany
| | - Anna Fogdell-Hahn
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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18
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Bartolini L, Libbey JE, Ravizza T, Fujinami RS, Jacobson S, Gaillard WD. Viral Triggers and Inflammatory Mechanisms in Pediatric Epilepsy. Mol Neurobiol 2018; 56:1897-1907. [PMID: 29978423 DOI: 10.1007/s12035-018-1215-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/27/2018] [Indexed: 12/21/2022]
Abstract
Experimental and clinical findings suggest a crucial role for inflammation in the onset of pediatric seizures; this mechanism is not targeted by conventional antiepileptic drugs and may contribute to refractory epilepsy. Several triggers, including infection with neurotropic viruses such as human herpesvirus 6 (HHV-6), other herpesviruses, and picornaviruses, appear to induce activation of the innate and adaptive immune systems, which results in several neuroinflammatory responses, leading to enhanced neuronal excitability, and ultimately contributing to epileptogenesis. This review discusses the proposed mechanisms by which infection with herpesviruses, and particularly with HHV-6, and ensuing inflammation may lead to seizure generation, and later development of epilepsy. We also examine the evidence that links herpesvirus and picornavirus infections with acute seizures and chronic forms of epilepsy. Understanding the mechanisms by which specific viruses may trigger a cascade of alterations in the CNS ultimately leading to epilepsy appears critical for the development of therapeutic agents that may target the virus or inflammatory mechanisms early and prevent progression of epileptogenesis.
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Affiliation(s)
- Luca Bartolini
- Clinical Epilepsy Section, National Institute of Neurological Disorders and Stroke, NIH, Building 10, room 7-5680, 10 Center Drive, Bethesda, MD, 20814, USA. .,Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, NIH, 10 Center Drive, Bethesda, MD, 20892, USA. .,Center for Neuroscience, Children's National Medical Center, George Washington University, 111 Michigan Ave NW, Washington, DC, 20010, USA.
| | - Jane E Libbey
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Teresa Ravizza
- Neuroscience Department, IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Via La Masa 19, 20156, Milan, Italy
| | - Robert S Fujinami
- Department of Pathology, University of Utah School of Medicine, 15 North Medical Drive East, 2600 EEJMRB, Salt Lake City, UT, 84112, USA
| | - Steven Jacobson
- Division of Neuroimmunology and Neurovirology, National Institute of Neurological Disorders and Stroke, NIH, 10 Center Drive, Bethesda, MD, 20892, USA
| | - William D Gaillard
- Center for Neuroscience, Children's National Medical Center, George Washington University, 111 Michigan Ave NW, Washington, DC, 20010, USA
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19
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Wipfler P, Dunn N, Beiki O, Trinka E, Fogdell-Hahn A. The Viral Hypothesis of Mesial Temporal Lobe Epilepsy – Is Human Herpes Virus-6 the Missing Link? A systematic review and meta-analysis. Seizure 2018; 54:33-40. [DOI: 10.1016/j.seizure.2017.11.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/21/2017] [Accepted: 11/24/2017] [Indexed: 12/26/2022] Open
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20
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Human Herpesvirus 6B Induces Hypomethylation on Chromosome 17p13.3, Correlating with Increased Gene Expression and Virus Integration. J Virol 2017; 91:JVI.02105-16. [PMID: 28298607 DOI: 10.1128/jvi.02105-16] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 03/03/2017] [Indexed: 12/21/2022] Open
Abstract
Human herpesvirus 6B (HHV-6B) is a neurotropic betaherpesvirus that achieves latency by integrating its genome into host cell chromosomes. Several viruses can induce epigenetic modifications in their host cells, but no study has investigated the epigenetic modifications induced by HHV-6B. This study analyzed methylation with an Illumina 450K array, comparing HHV-6B-infected and uninfected Molt-3 T cells 3 days postinfection. Bisulfite pyrosequencing was used to validate the Illumina results and to investigate methylation over time in vitro Expression of genes was investigated using quantitative PCR (qPCR), and virus integration was investigated with PCR. A total of 406 CpG sites showed a significant HHV-6B-induced change in methylation in vitro Remarkably, 86% (351/406) of these CpGs were located <1 Mb from chromosomal ends and were all hypomethylated in virus-infected cells. This was most evident at chromosome 17p13.3, where HHV-6B had induced CpG hypomethylation after 2 days of infection, possibly through TET2, which was found to be upregulated by the virus. In addition, virus-induced cytosine hydroxymethylation was observed. Genes located in the hypomethylated region at 17p13.3 showed significantly upregulated expression in HHV-6B-infected cells. A temporal experiment revealed HHV-6B integration in Molt-3 cell DNA 3 days after infection. The telomere at 17p has repeatedly been described as an integration site for HHV-6B, and we show for the first time that HHV-6B induces hypomethylation in this region during acute infection, which may play a role in the integration process, possibly by making the DNA more accessible.IMPORTANCE The ability to establish latency in the host is a hallmark of herpesviruses, but the mechanisms differ. Human herpesvirus 6B (HHV-6B) is known to establish latency through integration of its genome into the telomeric regions of host cells, with the ability to reactivate. Our study is the first to show that HHV-6B specifically induces hypomethylated regions close to the telomeres and that integrating viruses may use the host methylation machinery to facilitate their integration process. The results from this study contribute to knowledge of HHV-6B biology and virus-host interaction. This in turn will lead to further progress in our understanding of the underlying mechanisms by which HHV-6B contributes to pathological processes and may have important implications in both disease prevention and treatment.
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21
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Matsuda T, Shimakawa S, Toshikawa H, Hatanaka M, Fukui M, Mori A, Tamai H. Hippocampal signal abnormality on the first day of illness in acute encephalopathy with biphasic seizures and late reduced diffusion caused by HHV-6 infection. Brain Dev 2016; 38:943-946. [PMID: 27595174 DOI: 10.1016/j.braindev.2016.05.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Revised: 04/30/2016] [Accepted: 05/02/2016] [Indexed: 11/28/2022]
Abstract
We report a 13-month-old girl who developed acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) with transient reduced diffusion in the hippocampus and anterior commissure on diffusion-weighted imaging (DWI), which was performed on the first day after febrile status epilepticus (FSE) as the initial neurological symptom of AESD. DWI just after late seizures showed high signal intensity lesions in both left hippocampus and anterior commissure, and left extratemporal and occipital subcortical white matter. HHV-6 DNA was positive in both blood and cerebrospinal fluid samples. DWI at two months after onset showed atrophy in the left mesial temporal lobe and extratemporal and occipital lobe without the signal abnormalities. Although it has been reported that magnetic resonance images tend to show no acute abnormality during the first two days in typical AESD, transient reduced diffusion could be found on the DWI performed on the first day of AESD.
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Affiliation(s)
- Takuya Matsuda
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan
| | - Shuichi Shimakawa
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan.
| | | | - Mari Hatanaka
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan
| | - Miho Fukui
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan
| | - Atsushi Mori
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan
| | - Hiroshi Tamai
- Department of Pediatrics, Osaka Medical College, Takatsuki, Osaka, Japan
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22
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Mohammadpour Touserkani F, Gaínza-Lein M, Jafarpour S, Brinegar K, Kapur K, Loddenkemper T. HHV-6 and seizure: A systematic review and meta-analysis. J Med Virol 2016; 89:161-169. [PMID: 27272972 DOI: 10.1002/jmv.24594] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2016] [Indexed: 12/26/2022]
Abstract
Human herpesvirus-6 (HHV-6) is a common infection in childhood. This systematic review aims to assess the relationship between HHV-6 infection and seizure disorders based on available literature. MEDLINE database was searched using a search strategy. We included studies that were published after 1993 in English, and described patients with HHV-6 infection and accompanying seizure or status epilepticus. We identified 503 articles, and included 147 studies. Meta-analysis results showed a 0.21 detection rate of HHV-6 in febrile seizure patients. In the febrile seizure group (110 cases), 76 patients had simple and 34 had complex febrile seizures. Patients with "HHV-6 infection and status epilepticus" had a mean age of 16.24 months. In children with febrile illnesses, a higher index of clinical suspicion for HHV-6 infection may be required. Further studies including CSF and brain tissue may be needed to validate relationships between HHV6 infection and epilepsy. J. Med. Virol. 89:161-169, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Fatemeh Mohammadpour Touserkani
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
| | - Marina Gaínza-Lein
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.,Universidad Austral de Chile, Valdivia, Chile
| | - Saba Jafarpour
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Katelyn Brinegar
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.,Division of Biomedical Engineering, Department of Medicine, Biomaterials Innovation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts.,Harvard-Massachusetts Institute of Technology Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Kush Kapur
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Tobias Loddenkemper
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
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23
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Lin CTM, Leibovitch EC, Almira-Suarez MI, Jacobson S. Human herpesvirus multiplex ddPCR detection in brain tissue from low- and high-grade astrocytoma cases and controls. Infect Agent Cancer 2016; 11:32. [PMID: 27462365 PMCID: PMC4960850 DOI: 10.1186/s13027-016-0081-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 05/25/2016] [Indexed: 11/19/2022] Open
Abstract
Background Glioblastoma (GBM) is a fatal CNS malignancy, representing 50 % of all gliomas with approximately 12–18 months survival time after initial diagnosis. Recently, the human herpesvirus cytomegalovirus (CMV) has been suggested to have an oncogenic role, yet this association remains controversial. In addition, human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have also been associated with low-grade gliomas, but few studies have examined HHV-6 and EBV in glioblastomas. Droplet digital PCR (ddPCR) is a highly precise diagnostic tool that enables the absolute quantification of target DNA. This study examines the association between multiple human herpesviruses and astrocytomas. Methods This study analyzed 112 brain tissue specimens, including 45 glioblastoma, 12 astrocytoma grade III, 2 astrocytoma grade II, 4 astrocytoma grade I, and 49 controls. All brain tissue samples were de-identified and pathologically confirmed. Each tissue block was sectioned for DNA extraction and CMV, EBV, HHV-6A and HHV-6B, and a cellular housekeeping gene were amplified by ddPCR. Results Neither CMV nor HHV-6A were detected in any of the astrocytoma samples. However, HHV-6B (p = 0.147) and EBV (p = 0.049) had a higher positivity frequency in the GBM compared to the controls. Conclusion The undetectable CMV DNA in the astrocytoma cohort does not support the observation of an increased prevalence of CMV DNA in GBM, as reported in other studies. EBV has a significantly higher positivity in the GBM cohort compared to the controls, while HHV-6B has a higher but not statistically significant positivity in the case cohort. Whether these viruses play an oncogenic role in GBM remains to be further investigated.
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Affiliation(s)
- Cheng-Te Major Lin
- The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA ; School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA
| | - Emily C Leibovitch
- The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA ; School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA
| | - M Isabel Almira-Suarez
- School of Medicine and Health Sciences, The George Washington University, Ross Hall 2300 Eye Street, NW, Washington, DC 20037 USA
| | - Steven Jacobson
- The National Institute of Neurological Disorders and Stroke, National Institutes of Health, BG 10 RM 5C103 10 Center Dr., Bethesda, MD 20892 USA
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24
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Leibovitch EC, Jacobson S. Human Herpesvirus 6 as a Viral Trigger in Mesial Temporal Lobe Epilepsy. J Infect Dis 2015; 212:1011-3. [PMID: 25840442 DOI: 10.1093/infdis/jiv162] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 01/24/2023] Open
Affiliation(s)
- Emily C Leibovitch
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland Institute for Biomedical Sciences, School of Medicine and Health Sciences, The George Washington University, Washington D.C
| | - Steven Jacobson
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
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25
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Huang C, Yan B, Lei D, Si Y, Li H, Chen MW, Li L, Chen F, Zhou Q, Zhou D, Li JM. Apolipoprotein 4 may increase viral load and seizure frequency in mesial temporal lobe epilepsy patients with positive human herpes virus 6B. Neurosci Lett 2015; 593:29-34. [DOI: 10.1016/j.neulet.2014.12.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 12/28/2014] [Accepted: 12/31/2014] [Indexed: 10/24/2022]
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26
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Esposito L, Drexler JF, Braganza O, Doberentz E, Grote A, Widman G, Drosten C, Eis-Hübinger AM, Schoch S, Elger CE, Becker AJ, Niehusmann P. Large-scale analysis of viral nucleic acid spectrum in temporal lobe epilepsy biopsies. Epilepsia 2014; 56:234-43. [PMID: 25530314 DOI: 10.1111/epi.12890] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Chronic inflammatory processes are important promotors of temporal lobe epilepsy (TLE) development. Based on human herpesvirus 6 (HHV-6) DNA detection in brain tissue from patients with TLE, an association of persistent viral infection with TLE has been discussed. Individual studies reported increased HHV-6 DNA in patients with clinical signs of previous inflammatory brain reaction, that is, febrile seizures or meningoencephalitis. However, detection rates vary considerably between different studies. Here we performed a large-scale analysis of viral DNA/RNA spectrum in high-quality TLE biopsies. In addition to all Herpesviridae, we addressed potentially relevant neurotropic RNA viruses. METHODS DNA and RNA were extracted from 346 fresh-frozen tissue samples removed by epilepsy surgery. Real-time polymerase chain reaction (PCR) and nested PCR were performed for Herpesviridae and RNA viruses, respectively. Clinical data were analyzed for earlier signs of inflammatory brain reactions. Fresh-frozen hippocampal tissue samples from patients without chronic central nervous system (CNS) disease served as controls (n = 62). Seven previous PCR studies with overall 178 TLE patients were additionally analyzed regarding a correlation of clinical parameters and HHV-6 detection. RESULTS PCR revealed HHV-6B DNA in 34 specimens (9.8%) from TLE patients. HHV-6B DNA was also present in eight control samples (12.9%; p > 0.05), but showed a lower virus concentration (p < 0.001). Other herpesviruses and RNA viruses were virtually absent. In patients with clinical signs of previous brain inflammation, HHV-6B DNA was observed in 15.0%, whereas only 6.3% of the samples from patients without febrile seizures or meningoencephalitis were positive for HHV-6B DNA (p < 0.05). A meta-analysis of the eight HHV-6 PCR studies revealed similar results. SIGNIFICANCE This biopsy-based study shows no differences in frequency of HHV-6B DNA detection between TLE patients and controls. These results do not support the hypothesis of a persistent HHV-6B infection as a major pathogenetic factor in TLE. However, the higher virus load in TLE patients and the increased detection rate of HHV-6B DNA in patients with previous inflammatory brain reactions require further investigations.
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Affiliation(s)
- Laura Esposito
- Department of Neuropathology, University of Bonn Medical Center, Bonn, Germany
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Cheng L, Lei S, Chen SH, Hong Z, Yang TH, Li L, Chen F, Li HX, Zhou D, Li JM. Pretreatment with intravenous levetiracetam in the rhesus monkey Coriaria lactone-induced status epilepticus model. J Neurol Sci 2014; 348:111-20. [PMID: 25579413 DOI: 10.1016/j.jns.2014.11.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 11/08/2014] [Accepted: 11/11/2014] [Indexed: 02/05/2023]
Abstract
PURPOSE To investigate the antiepileptic and protective effects of intravenous levetiracetam (iv LEV) in the rhesus monkey model of acute status epilepticus (SE). METHODS Thirty minutes before intraperitoneal induction of SE by Coriaria lactone (CL), rhesus monkeys were treated with LEV (15 or 150 mg/kg) delivered intravenously as a single bolus. CL dose and epileptic behavior were recorded. Electroencephalography (EEG) was performed before and during the experiment. All rhesus monkeys were killed after 1-month video monitoring and processed for pathological investigation of neuronal injury, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining, and glial fibrillary acidic protein (GFAP) staining. RESULTS No animal exhibited spontaneous seizures during 1-month video monitoring. Development of acute SE was significantly inhibited in the group given 150 mg/kg LEV, compared with controls and the 15 mg/kg LEV group. Delayed latency, reduction of SE duration, decreased cumulative time of tonic convulsions, slight severity of SE, and a high CL induction dose were observed in the high LEV dose group (p<0.05). The EEG showed less frequent epileptic discharges in the group administered with 150 mg/kg LEV. Hematoxylin and eosin (H&E) staining, ultrastructural examination, TUNEL and GFAP staining revealed serious damage, including neuron loss, swollen mitochondrion, and strong positivity for TUNEL in the hippocampus and thalamus of controls, whereas moderate damage in the group administered with 15 mg/kg LEV, and very mild damage in the 150 mg/kg LEV group. Gliosis was found in the hippocampus of controls, not in the LEV groups and normal rhesus monkey. CONCLUSION The study supports the antiepileptic and protective effect of pretreatment with intravenous LEV in rhesus monkey model with SE.
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Affiliation(s)
- Lan Cheng
- Department of Neurology, West China Hospital, Sichuan University, PR China
| | - Song Lei
- Department of Pathology, West China Hospital, Sichuan University, PR China
| | - Si-Han Chen
- Department of Neurology, West China Hospital, Sichuan University, PR China
| | - Zhen Hong
- Department of Neurology, West China Hospital, Sichuan University, PR China
| | - Tian-Hua Yang
- Department of Neurology, West China Hospital, Sichuan University, PR China
| | - Li Li
- Laboratory of Transplant, West China Hospital, Sichuan University, PR China
| | - Fei Chen
- Laboratory of Transplant, West China Hospital, Sichuan University, PR China
| | - Hong-Xia Li
- National Chengdu Center for Safety Evaluation of Traditional Chinese Medicine, West China Hospital, Sichuan University, PR China
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, PR China.
| | - Jin-Mei Li
- Department of Neurology, West China Hospital, Sichuan University, PR China.
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Tesini BL, Epstein LG, Caserta MT. Clinical impact of primary infection with roseoloviruses. Curr Opin Virol 2014; 9:91-6. [PMID: 25462439 DOI: 10.1016/j.coviro.2014.09.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Revised: 09/17/2014] [Accepted: 09/22/2014] [Indexed: 01/31/2023]
Abstract
The roseoloviruses, human herpesvirus-6A -6B and -7 (HHV-6A, HHV-6B and HHV-7) cause acute infection, establish latency, and in the case of HHV-6A and HHV-6B, whole virus can integrate into the host chromosome. Primary infection with HHV-6B occurs in nearly all children and was first linked to the clinical syndrome roseola infantum. However, roseolovirus infection results in a spectrum of clinical disease, ranging from asymptomatic infection to acute febrile illnesses with severe neurologic complications and accounts for a significant portion of healthcare utilization by young children. Recent advances have underscored the association of HHV-6B and HHV-7 primary infection with febrile status epilepticus as well as the role of reactivation of latent infection in encephalitis following cord blood stem cell transplantation.
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Affiliation(s)
- Brenda L Tesini
- Division of Infectious Diseases, Department of Pediatrics, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 690, Rochester, NY 14642, USA
| | - Leon G Epstein
- Departments of Pediatrics and Neurology, Feinberg School of Medicine, Northwestern University and the Ann & Robert H. Lurie Children's Hospital of Chicago, Box 51, 225 E Chicago Ave, Chicago, IL 60611, USA
| | - Mary T Caserta
- Division of Infectious Diseases, Department of Pediatrics, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Box 690, Rochester, NY 14642, USA.
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Li JM, Huang C, Yan B, Wang W, Zhou Q, Sander JW, Zhou D. HHV-7 in adults with drug-resistant epilepsy: a pathological role in hippocampal sclerosis? J Clin Virol 2014; 61:387-92. [PMID: 25282530 DOI: 10.1016/j.jcv.2014.08.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/18/2014] [Accepted: 08/21/2014] [Indexed: 02/05/2023]
Abstract
BACKGROUND Human herpesvirus-7 (HHV-7) is a β-herpesvirus associated with febrile seizures. No association between HHV-7 and epilepsy has been confirmed. OBJECTIVES The aim of this study was to investigate the presence of HHV-7 protein (KR4) in brain tissue from patients with drug-resistant epilepsy and to determine whether inflammatory molecules are activated in the presence of HHV-7 infection. STUDY DESIGN We used immunohistochemistry (IHC) to detect HHV-7 protein KR4 in samples from 305 patients with drug-resistant epilepsy. Liquid nitrogen-preserved hippocampal sclerosis (HS) samples from 63 of these patients were available, and we used nested polymerase chain reaction (PCR) to detect HHV-7 DNA. Inflammatory molecules including tumor necrosis factor-alpha (TNF-α), transforming growth factor-beta (TGF-β), interleukin-1 (IL-1) and interleukin-6 (IL-6) were identified by real-time PCR (rt-PCR) and IHC. RESULTS AND CONCLUSIONS The study sample included 201 male subjects. The mean age was 23.9, SD 6.2 years (range 15-45). HS was the pathology in 69 samples (23%). The HHV-7 protein was detected in 27 (9%) of the 305 samples and in none of the 42 controls. The factors associated with HHV-7 infection were HS (11/69), glial scar (8/58), arachnoid cyst (2/21), focal cortical dysplasia (2/31) and vascular malformation (4/52). HHV-7 antigen was distributed mainly in the cytoplasm of astrocyte and oligodendrocyte in HS samples. HHV-7 DNA was detected in 20 of the 63 nitrogen preserved HS samples. The expression of TGF-β was up-regulated in samples that were positive for the HHV-7 protein and was mainly detected in neurons. This finding suggests a possible association between HHV-7 positivity, activation of TGF-β and drug-resistant epilepsy, especially HS, but these data need to be replicated.
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Affiliation(s)
- Jin-Mei Li
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Cheng Huang
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Bo Yan
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Wei Wang
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China
| | - Qiao Zhou
- Department of Pathology, West China Hospital of Sichuan University, Chengdu, China
| | - Josemir W Sander
- NIHR University College London Hospital Biomedical Research Centre, UCL Institute of Neurology, China
| | - Dong Zhou
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, China.
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30
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Ablashi D, Agut H, Alvarez-Lafuente R, Clark DA, Dewhurst S, DiLuca D, Flamand L, Frenkel N, Gallo R, Gompels UA, Höllsberg P, Jacobson S, Luppi M, Lusso P, Malnati M, Medveczky P, Mori Y, Pellett PE, Pritchett JC, Yamanishi K, Yoshikawa T. Classification of HHV-6A and HHV-6B as distinct viruses. Arch Virol 2014; 159:863-70. [PMID: 24193951 PMCID: PMC4750402 DOI: 10.1007/s00705-013-1902-5] [Citation(s) in RCA: 225] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/18/2013] [Indexed: 12/18/2022]
Abstract
Shortly after the discovery of human herpesvirus 6 (HHV-6), two distinct variants, HHV-6A and HHV-6B, were identified. In 2012, the International Committee on Taxonomy of Viruses (ICTV) classified HHV-6A and HHV-6B as separate viruses. This review outlines several of the documented epidemiological, biological, and immunological distinctions between HHV-6A and HHV-6B, which support the ICTV classification. The utilization of virus-specific clinical and laboratory assays for distinguishing HHV-6A and HHV-6B is now required for further classification. For clarity in biological and clinical distinctions between HHV-6A and HHV-6B, scientists and physicians are herein urged, where possible, to differentiate carefully between HHV-6A and HHV-6B in all future publications.
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Affiliation(s)
- Joshua A Hill
- Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, USA.
| | - Nagagopal Venna
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
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Amirian ES, Adler-Storthz K, Scheurer ME. Associations between human herpesvirus-6, human papillomavirus and cervical cancer. Cancer Lett 2013; 336:18-23. [PMID: 23624298 DOI: 10.1016/j.canlet.2013.04.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/17/2013] [Accepted: 04/17/2013] [Indexed: 01/29/2023]
Abstract
Cervical cancer (CxCa) is the second most common cancer among women globally. Human papillomavirus (HPV) infection is thought to be a necessary, but not sufficient, causal factor in CxCa development. Why some women are able to clear HPV infection with no adverse effects, whereas others develop cancer, remains unclear. HHV-6 has demonstrated transformative abilities and has been shown to be present in the genital tract. However, based on the current evidence, we cannot conclude that HHV-6 is a co-factor in HPV-associated carcinogenesis. Nonetheless, future research is warranted because of several crucial gaps in the literature.
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Affiliation(s)
- E Susan Amirian
- Dan L Duncan Cancer Center and Department of Pediatrics, Baylor College of Medicine, 1 Baylor Plaza MSBCM305, Houston, TX 77030, USA
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