Related Experiment Video
Updated: Apr 15, 2026
A Model for Epilepsy of Infectious Etiology using Theiler's Murine Encephalomyelitis Virus
Published on: June 23, 2022
Pathogenic Role of Human Herpesvirus 6B Infection in Mesial Temporal Lobe Epilepsy
Yoshiki Kawamura1, Ai Nakayama1, Taichi Kato1
1Department of Pediatrics, Fujita Health University School of Medicine.
Background:
Human herpesvirus 6B (HHV-6B) is the causative agent for exanthem subitum. HHV-6B was associated with mesial temporal sclerosis (MTS), leading to mesial temporal lobe epilepsy (MTLE). In this study, we sought to elucidate the pathogenic role of HHV-6B in patients with MTLE.
Methods:
Seventy-five intractable MTLE patients, including 52 MTS patients and 23 non-MTS patients, were enrolled in this study. Resected hippocampus, amygdala, and mixed samples of amygdala and uncus samples were examined by real-time polymerase chain reaction (PCR) and reverse-transcriptase PCR to detect viral DNA and messenger RNA (mRNA), respectively. Host gene expressions, including neural markers, were measured using the TaqMan Gene Expression Assay.
Results:
Detection of HHV-6 DNA was higher in MTS patients than non-MTS patients (median/interquartile range: 19.1/0-89.2 vs 0.0/0.0-0.0 copies/µg DNA; P = .004). HHV-6B viral DNA was determined in 12/27 HHV-6 DNA-positive samples, and no HHV-6B mRNA were detected in all samples. In MTS patients, expression of monocyte chemotactic protein-1 (P = .029) and glial fibrillary acidic protein (P = .043) were significantly higher in the amygdala samples with HHV-6 DNA than those without viral DNA.
Conclusions:
This study suggests that HHV-6B may play an important role in the pathogenesis of MTS via modification of host gene expression.
Insights
Human herpesvirus 6B (HHV-6B) DNA is more prevalent in mesial temporal sclerosis (MTS) patients with epilepsy. HHV-6B may contribute to MTS by altering host gene expression in the brain.
Area of Science:
- Neurology
- Virology
- Molecular Biology
Background:
- Human herpesvirus 6B (HHV-6B) is linked to exanthem subitum and mesial temporal sclerosis (MTS).
- MTS is a common cause of intractable mesial temporal lobe epilepsy (MTLE).
Purpose of the Study:
- To investigate the pathogenic role of HHV-6B in patients with MTLE.
- To determine the presence and impact of HHV-6B in MTLE with and without MTS.
Main Methods:
- Real-time and reverse-transcriptase PCR were used to detect HHV-6B DNA and mRNA in resected brain tissues from 75 MTLE patients.
- Host gene expression, including neural markers, was quantified using TaqMan Gene Expression Assays.
Main Results:
- HHV-6 DNA detection was significantly higher in MTS patients compared to non-MTS patients (P = .004).
- HHV-6B DNA was found in a subset of positive samples, but no HHV-6B mRNA was detected.
- MTS patients with HHV-6 DNA showed elevated expression of monocyte chemotactic protein-1 and glial fibrillary acidic protein in amygdala samples.
Conclusions:
- HHV-6B DNA presence correlates with MTS in MTLE patients.
- HHV-6B may contribute to MTS pathogenesis by modulating host gene expression, particularly in inflammatory and glial pathways.
Related Concept Videos
01:27Cytomegalovirus Disease
01:25Arboviral Encephalitis