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An intriguing area of research has demonstrated the ability of extracellular vesicles (EVs) as biological vehicles for microRNAs (miRNAs) transfer. Mesenchymal stem cells (MSCs) produce large amounts of EVs. Rat models of ischemia/reperfusion (I/R) were established to explore the expression profile of thioredoxin-interacting protein (TXNIP), which was then knocked-down to investigate its effects on myocardial remodeling, followed by detection on myocardial infarction size (MIS), myocardial collagen volume fraction (CVF) and cardiomyocyte apoptosis. MSCs-derived EVs carrying miR-150-5p were cultured with neonatal cardiomyocytes under hypoxia/hypoglycemia condition for in vitro exploration and intramyocardially injected into I/R rats for in vivo exploration. I/R-induced rats presented higher TXNIP levels and lower miR-150-5p levels, along with increased cardiomyocyte apoptosis. miR-150-5p in MSCs was transferred through EVs to cardiomyocytes, leading to suppressed myocardial remodeling, as reflected by smaller MIS and CVF and suppressed cardiomyocyte apoptosis. I/R-treated rats injected with MSCs-derived EVs containing miR-150-5p showed a reduction in myocardial remodeling associated with the downregulation of TXNIP, which may be clinically applicable for treatment of I/R.

Purpose: This study aimed to investigate whether long noncoding RNA (lncRNA) LINC00467 could regulate proliferative and invasive abilities of glioma cells via p53 and DNA methyltransferase 1 (DNMT1), so as to participate in the occurrence and progression of glioma. Methods: LINC00467 expression in glioma was analyzed by GEPIA database and LINC00467 expression in glioma cell lines was detected by qRT-PCR. The regulatory effects of LINC00467 and p53 on proliferative, invasive capacities and cell cycle were conducted by CCK-8 and EdU assays, transwell assay and flow cytometry, respectively. The binding conditions between LINC00467, DNMT1 and p53 were determined by RNA immunoprecipitation (RIP) and Chromatin immunoprecipitation (ChIP) assays. Western blot was conducted to determine whether LINC00467 could regulate p53 in glioma cells. Finally, rescue experiments were carried out to evaluate whether LINC00467 regulates proliferative and invasive abilities of glioma cells through p53. Results: The expression of LINC00467 was significantly up-regulated in tumor samples than that in normal samples, which was not correlated with patient survival time. Besides, expression of LINC00467 was higher in glioma cells than that of negative control cells. Upregulation of LINC00467 promoted proliferative and invasive abilities, and accelerated cell cycle in G0/G1 phase of U87 and LN229 cells. The results of RIP and ChIP assays demonstrated that LINC00467 could bind to DNMT1 and inhibit p53 expression. Overexpression of p53 partially reversed the enhancement of LINC00467 on proliferative and invasive abilities of glioma cells. Conclusion: These results indicated that high expression of LINC00467 could promote proliferative and invasive abilities of glioma cells through targeting inhibition of p53 expression by binding to DNMT1.

Human herpesvirus 6 (HHV-6) belongs to the betaherpesvirus subfamily and is divided into two distinct species, HHV-6A and HHV-6B. HHV-6 can infect nerve cells and is associated with a variety of nervous system diseases. Recently, the association of HHV-6A infection with Alzheimer's disease (AD) has been suggested. The main pathological phenomena of AD are the accumulation of β-amyloid (Aβ), neurofibrillary tangles, and neuroinflammation; however, the specific molecular mechanism of pathogenesis of AD is not completely clear. In this study, we focused on the effect of HHV-6A U4 gene function on Aβ expression. Coexpression of HHV-6A U4 with amyloid precursor protein (APP) resulted in inhibition of ubiquitin-mediated proteasomal degradation of APP. Consequently, accumulation of β-amyloid peptide (Aβ), insoluble neurofibrillary tangles, and loss of neural cells may occur. Immunoprecipitation coupled with mass spectrometry (IP-MS) showed that HHV-6A U4 protein interacts with E3 ubiquitin ligase composed of DDB1 and cullin 4B, which is also responsible for APP degradation. We hypothesize that HHV-6A U4 protein competes with APP for binding to E3 ubiquitin ligase, resulting in the inhibition of APP ubiquitin modification and clearance. Finally, this leads to an increase in APP expression and Aβ deposition, which are the hallmarks of AD. These findings provide novel evidence for the etiological hypothesis of AD, which can contribute to the further analysis of the role of HHV-6A in AD. IMPORTANCE The association of HHV-6A infection with Alzheimer’s disease has attracted increasing attention, although its role and molecular mechanism remain to be established. Our results here indicate that HHV-6A U4 inhibits amyloid precursor protein (APP) degradation. U4 protein interacts with CRLs (cullin-RING E3 ubiquitin-protein ligases), which is also responsible for APP degradation. We propose a model in which U4 competitively binds to CRLs with APP, resulting in APP accumulation and Aβ generation. Our findings provide new insights into the etiological hypothesis of HHV-6A in AD that can help further analyses.

Our previous studies indicate that long noncoding RNA (lncRNA) LINC00467 can act as an oncogene to participate in the malignant progression of glioma, but the underlying molecular mechanism remains to be studied further. This study aimed to explore the biological role of the LINC00467/miR-339-3p/ inositol hexakisphosphate kinase 2 (IP6K2) regulatory axis in glioma. The Cancer Genome Atlas (TCGA), Oncomine databases and reverse transcription‑quantitative PCR (RT‑qPCR) were used to analyze IP6K2 expression in glioma. RT-PCR, EdU and transwell assays were conducted to observe the effect of IP6K2 on glioma cell proliferation, migration and invasion. Using bioinformatics analysis, RT-PCR, and dual luciferase reporter gene assay, the potential role of the LINC00467/miR-339-3p/IP6K2 regulatory axis in glioma was verified. The results showed that IP6K2 was up-regulated in glioma tissues and cell lines. Moreover, the expression level of IP6K2 was correlated with the clinical features of glioma patients.

Human herpesviruses 6A and 6B (HHV-6A and HHV-6B, respectively) are two virus species in the betaherpesvirus subfamily that exhibit T cell tropism. CD46 and CD134 are the cellular receptors for HHV-6A and HHV-6B, respectively. Interestingly, the efficiency of HHV-6A/6B entry is different among different types of target cells despite similar receptor expression levels on these cells. Here, we found that the cellular factor gp96 (also known as glucose-regulated protein 94 [GRP94]) is expressed on the cell surface and interacts with viral glycoprotein Q1 (gQ1) during virus entry. gp96 cell surface expression levels are associated with the efficiency of HHV-6A and HHV-6B entry into target cells. Both loss-of-function and gain-of-function experiments indicated that gp96 plays an important role in HHV-6 infection. Our findings provide new insight into the HHV-6 entry process and might suggest novel therapeutic targets for HHV-6 infection. IMPORTANCE Although new clinical importance has been revealed for human herpesviruses 6A (HHV-6A) and 6B, much is still unknown about the life cycles of these viruses in target cells. We identified a novel cellular factor, gp96, that is critical for both HHV-6A and -6B entry into host cells. As gp96 can function as an adjuvant in vaccine development for both infectious agents and cancers, it can be a potential therapeutic target for infection by these two viruses.

Traumatic brain injury (TBI) refers to external force-induced brain damage, characterized with necrosis and cell loss in cerebral cortex. Interestingly, a plant-extract named formononetin (FN) is found to possess promising pharmacological activities, including cellular neuroprotection. Thus, we propose that FN may exert biological protection against TBI and discuss the underlying mechanism. In the current study, a rat TBI model was established via Feeney's classical method, followed by different concentrations of FN treatment. Nissl-special and DAPI-labeled stains were utilized to assess the proliferation of cortical neurons nearing lesioned tissue. The contents of interleukin-6 (IL6), tumor necrosis factor (TNF-α), and interleukin-10 (IL10) in serum and the cortical neurons were determined by ELISA. Further, intracephalic IL10 expression levels were detected through immunoassay and RT-PCR. Interestingly, the results exhibited within the FN-treated TBI rat model indicated elevated cortical proliferation. The levels of IL10 in serum and the cortical neurons were increased following FN treatments, while TNF-α and IL6 levels in the blood were decreased. In addition, both mRNA and protein expression levels of IL10 in the FN-treated TBI rat model were up-regulated in a dose-dependent manner. Collectively, our present findings indicate that FN provides effective neuroprotection against TBI, likely by activating IL10 expression in cortical neurons nearing lesioned tissue to inhibit neuroinflammatory reaction.

Human herpes virus 6 (HHV-6) is a common human pathogen that is most often detected in hematopoietic cells. Although human cells harboring chromosomally integrated HHV-6 can be generated in vitro, the availability of such cell lines originating from in vivo tissues is limited. In this study, chromosomally integrated HHV-6B has been identified in a human vascular endothelial cell line, HUV-EC-C (IFO50271), derived from normal umbilical cord tissue. Sequence analysis revealed that the viral genome was similar to the HHV-6B HST strain. FISH analysis using a HHV-6 DNA probe showed one signal in each cell, detected at the distal end of the long arm of chromosome 9. This was consistent with a digital PCR assay, validating one copy of the viral DNA. Because exposure of HUV-EC-C to chemicals did not cause viral reactivation, long term cell culture of HUV-EC-C was carried out to assess the stability of viral integration. The growth rate was altered depending on passage numbers, and morphology also changed during culture. SNP microarray profiles showed some differences between low and high passages, implying that the HUV-EC-C genome had changed during culture. However, no detectable change was observed in chromosome 9, where HHV-6B integration and the viral copy number remained unchanged. Our results suggest that integrated HHV-6B is stable in HUV-EC-C despite genome instability. Electronic supplementary material The online version of this article (doi:10.1007/s10616-017-0119-y) contains supplementary material, which is available to authorized users.

Age-related declines in cell-mediated immunity (CMI) are associated with the incidence and severity of Herpes Zoster (HZ) infection. However, the level of Varicella-Zoster virus (VZV)-specific CMI associated with disease onset is unclear. This study aimed to examine factors associated with VZV-specific CMI, as measured by an interferon-gamma (IFN-γ) enzyme-linked immunospot (ELISPOT) assay, in a Japanese cohort. The study enrolled 365 subjects aged 60 years and over, all of whom were taking part in the Shozu Herpes Zoster (SHEZ) study and had undergone four sets of blood and intradermal reaction tests during a 3 year follow-up period. The VZV-specific immunity profile of each subject was assessed, and linear mixed effects models were constructed to analyze IFN-γ ELISPOT results in association with a combination of factors. The model that best explained the IFN-γ ELISPOT results was selected using the Akaike Information Criteria. The best-fit model consisted of age group as the only explanatory fixed-effect variable. The model showed that VZV-specific CMI, quantified as numbers of spots on the ELISPOT assay, among subjects aged 70-79 was on average 10.30 points lower than that among subjects aged 60-69. There was no statistically significant difference between subjects aged 70-79 and those aged 80-89. Age was the only factor significantly associated with the level of VZV-specific CMI, as measured by the IFN-γ ELISPOT assay. These results may represent an important step towards quantifying the relationship between VZV-specific CMI and the onset of HZ. J. Med. Virol. 89:313-317, 2017. © 2016 Wiley Periodicals, Inc.

Human herpesvirus 6 (HHV-6) glycoprotein B (gB) is an abundantly expressed viral glycoprotein required for viral entry and cell fusion, and is highly conserved among herpesviruses. The present study examined the function of HHV-6 gB cytoplasmic tail domain (CTD). A gB CTD deletion mutant was constructed which, in contrast to its revertant, could not be reconstituted. Moreover, deletion of gB cytoplasmic tail impaired the intracellular transport of gB protein to the trans-Golgi network (TGN). Taken together, these results suggest that gB CTD is critical for HHV-6 propagation and important for intracellular transportation.

Objective: To establish an animal model of cerebral hernia induced by acute intracranial hypertension for subsequent research in emergency medicine. Methods: Six Guangxi Ba-Ma mini-pigs were injected with autologous arterial blood by micropump to induce intracranial hematoma in the frontal and temporal parietal lobes. Changes in intracranial pressure (ICP), mean arterial blood pressure (MAP) and cerebral perfusion pressure (CPP) were observed during hematoma formation. Morphological changes and the occupying effects of intracranial hematoma were analyzed using computed tomography (CT) and magnetic resonance imaging (MRI) of the head. Results: ICP, MAP and CPP gradually increased during blood injection, and they began to slowly decrease at 10 min after injection, though they remained higher than before injection. These three parameters were significantly different before blood injection, immediately after injection and at 10 min after injection (P < 0.05). Head CT and MRI showed cerebral hernia induced by acute intracranial hypertension. Conclusion: Micropump injection of autologous arterial blood can lead to acute intracranial hypertension in mini-pigs, which may be a useful model of cerebral hernia.

Recently, human herpesvirus 6A and 6B (HHV-6A and HHV-6B) were classified into distinct species. Although these two viruses share many similarities, cell tropism is one of their striking differences, which is partially because of the difference in their entry machinery. Many glycoproteins of HHV-6A/B have been identified and analyzed in detail, especially in their functions during entry process into host cells. Some of these glycoproteins were unique to HHV-6A/B. The cellular factors associated with these viral glycoproteins (or glycoprotein complex) were also identified in recent years. Detailed interaction analyses were also conducted, which could partially prove the difference of entry machinery in these two viruses. Although there are still issues that should be addressed, all the knowledges that have been earned in recent years could not only help us to understand these viruses' entry mechanism well but also would contribute to the development of the therapy and/or prophylaxis methods for HHV-6A/B-associated diseases.

BACKGROUND This study aimed to investigate the therapeutic effect of low, medium, and high concentrations of medical ozone on trauma-induced lumbar disc herniation. MATERIAL AND METHODS A total of 80 patients were included and were grouped into a control group, a low medical ozone (20 μg/ml) group, a medium medical ozone (40 μg/ml) group, and a high medical ozone (60 μg/ml) group. The CT scan and enzyme-linked immunosorbent assay (ELISA) were used to detect IL-6 level, SOD activity, IgM, and IgG levels upon admission and at 6 and 12 months after follow-up. The area under the ROC curve (AUC) was calculated for visual analogue scale (VAS) and efficiency rate. RESULTS All patients showed disc retraction at 6- and 12-month follow-up; while patients in the medium medical ozone (40 μg/ml) group showed the greatest disc retraction rate. The IL-6, IgM, IgG, and VAS levels significantly decreased while SOD activity increased among all groups over time (p

All herpesviruses contain a tegument layer comprising a protein matrix; these proteins play key roles during viral assembly and egress. Here, liquid chromatography and tandem mass spectrometry analysis (LC–MS/MS) of proteins from human herpesvirus 6 (HHV-6)-infected cells revealed a possible association between two major tegument proteins, U14 and U11. This association was verified by immunoprecipitation experiments. Moreover, U11 protein was expressed during the late phase of infection and incorporated into virions. Finally, in contrast to its revertant, a U11 deletion mutant could not be reconstituted. Taken together, these results suggest that HHV-6 U11 is an essential gene for virus growth and propagation.

Human herpesvirus 6A (HHV-6A) U14 is a virion protein with little known function in virus propagation. Here, we elucidated its function by constructing and analyzing U14-mutated viruses. We found that U14 is essential for HHV-6A propagation. We then constructed a mutant virus harboring dysfunctional U14. This virus showed severely reduced growth and retarded maturation. Taken together, these data indicate that U14 plays an important role during HHV-6A maturation.

Objectives/Hypothesis The etiology of Ramsay Hunt syndrome (Hunt syndrome) is reactivation of latent varicella-zoster virus (VZV) in the geniculate ganglion of the facial nerve, leading to neuritis. Although the mechanism of the VZV reactivation is unclear, one possibility is that the reactivation involves a low level of VZV-specific cell-mediated immunity (CMI). The aim of this study was to clarify the characteristics of the VZV-specific CMI in Hunt syndrome compared to that in Bell's palsy, and to obtain clues to its role in the development of Hunt syndrome. Study Design Prospective study. Methods We determined the median spot numbers and examined VZV-specific CMI in patients with Hunt syndrome and with Bell's palsy using interferon-γ enzyme-linked immunospot (ELISPOT) assays. We analyzed the relationship between the value of VZV-specific CMI and days from disease onset. Results The median spot number in Hunt syndrome (87.3 spot-forming cells [SFCs]/4 × 105 peripheral blood mononuclear cells [PBMCs]) was higher than that in Bell's palsy (62.3 SFCs/4 × 105 PBMCs). Hunt syndrome showed a strong relationship between the ELISPOT count and days from onset (r = 0.65). Within the first 5 days from onset, no ELISPOT counts higher than 80 SFCs/4 × 105 PBMCs were observed. On the other hand, no correlation was observed between the ELISPOT count and days from onset in patients with Bell's palsy (r = −0.19). Conclusions These results suggest that VZV-specific CMI in Hunt syndrome is low at disease onset and increases rapidly thereafter. Consequently, reduced VZV-specific CMI may play an important role in the reactivation of VZV in the facial nerve, leading to Hunt syndrome. Level of Evidence 4 Laryngoscope, 126:E35–E39, 2016

Glycoprotein O (gO) is conserved among betaherpesviruses, but little is known about the maturation process of gO in human herpesvirus 6 (HHV-6). We found that HHV-6 gO maturation was accompanied by cleavage of its carboxyl terminus and required coexpression of gH and gL, which promoted the export of gO out of the endoplasmic reticulum (ER). Finally, we also found that gO was not required for HHV-6A growth in T cells.

Recently, human herpesvirus 6A and 6B (HHV-6A and HHV-6B) were classified into distinct species. Although these two viruses share many similarities, cell tropism is one of their striking differences, which is partially because of the difference in their entry machinery. Many glycoproteins of HHV-6A/B have been identified and analyzed in detail, especially in their functions during entry process into host cells. Some of these glycoproteins were unique to HHV-6A/B. The cellular factors associated with these viral glycoproteins (or glycoprotein complex) were also identified in recent years. Detailed interaction analyses were also conducted, which could partially prove the difference of entry machinery in these two viruses. Although there are still issues that should be addressed, all the knowledges that have been earned in recent years could not only help us to understand these viruses’ entry mechanism well but also would contribute to the development of the therapy and/or prophylaxis methods for HHV-6A/B-associated diseases.

Human herpesvirus 6A (HHV-6A) glycoprotein B (gB) is a glycoprotein consisting of 830 amino acids and is essential for the growth of the virus. Previously, we reported that a neutralizing monoclonal antibody (MAb) called 87-y-13 specifically reacts with HHV-6A gB, and we identified its epitope residue at asparagine (Asn) 347 on gB. In this study, we examined whether the epitope recognized by the neutralizing MAb is essential for HHV-6A infection. We constructed HHV-6A bacterial artificial chromosome (BAC) genomes harboring substitutions at Asn347, namely, HHV-6A BACgB(N347K) and HHV-6A BACgB(N347A). These mutant viruses could be reconstituted and propagated in the same manner as the wild type and their revertants, and MAb 87-y-13 could not inhibit infection by either mutant. In a cell-cell fusion assay, Asn at position 347 on gB was found to be nonessential for cell-cell fusion. In addition, in building an HHV-6A gB homology model, we found that the epitope of the neutralizing MAb is located on domain II of gB and is accessible to solvents. These results indicate that Asn at position 347, the linear epitope of the neutralizing MAb, does not affect HHV-6A infectivity. IMPORTANCE Glycoprotein B (gB) is one of the most conserved glycoproteins among all herpesviruses and is a key factor for virus entry. Therefore, antibodies targeted to gB may neutralize virus entry. Human herpesvirus 6A (HHV-6A) encodes gB, which is translated to a protein of about 830 amino acids (aa). Using a monoclonal antibody (MAb) for HHV-6A gB, which has a neutralizing linear epitope, we analyzed the role of its epitope residue, N347, in HHV-6A infectivity. Interestingly, this gB linear epitope residue, N347, was not essential for HHV-6A growth. By constructing a homology model of HHV-6A gB, we found that N347 was located in the region corresponding to domain II. Therefore, with regard to its neutralizing activity against HHV-6A infection, the epitope on gB might be exposed to solvents, suggesting that it might be a target of the immune system.

Recently, we identified a novel receptor, CD134, which interacts with the human herpesvirus 6B (HHV-6B) glycoprotein (g)H/gL/gQ1/gQ2 complex and plays a key role in the entry of HHV-6B into target cells. However, details of the interaction between the HHV-6B gH/gL/gQ1/gQ2 complex and CD134 were unknown. In this study, we identified a cysteine-rich domain (CRD), CDR2, of CD134 that is critical for binding to the HHV-6B glycoprotein complex and HHV-6B infection. Furthermore, we found that the expression of HHV-6B gQ1 and gQ2 subunits was sufficient for CD134 binding, which is different from the binding of human herpesvirus 6A (HHV-6A) to its receptor, CD46. Finally, we identified a region in gQ1 critical for HHV-6B gQ1 function. These results contribute much to our understanding of the interaction between this ligand and receptor. IMPORTANCE We identified the domain in HHV-6B entry receptor CD134 and the components in the HHV-6B gH/gL/gQ1/gQ2 complex required for ligand-receptor binding during HHV-6B infection. Furthermore, we identified domains in gQ1 proteins of HHV-6A and -6B and a key amino acid residue in HHV-6B gQ1 required for its function. These data should be the basis for further investigation of ligand-receptor interaction in the study of HHV-6A and -6B.

Based on genetic and antigenic differences and on their cell tropism, human herpes virus-6 (HHV-6) has been classified into two variants, HHV-6A and HHV-6B. Recently, these variants were re-classified as two different species. The HHV-6A glycoprotein complex, gH/gL/gQ1/gQ2 binds to its cellular receptor, CD46; however, the corresponding complex in HHV-6B rarely binds to CD46. To determine which viral molecules in the glycoprotein complex determine HHV-6A-CD46 binding, each molecule of the HHV-6A complex (i.e., gH, gL, gQ1, or gQ2) was replaced with the corresponding HHV-6B molecule, and the ability of the replaced protein to be incorporated into the complex and the ability of the complex to bind CD46 were examined. It was found that when all four glycoproteins were expressed, they were able to form a tetrameric complex. However, a complex formed by HHV-6A gH/gL/gQ1/gQ2 complexes replaced with HHV-6B gQ1 or gQ2 scarcely bind CD46, whereas HHV-6A complexes in which gH or gL was replaced with the HHV-6B molecules did bind it. These results indicate that HHV-6A gQ1 and gQ2 play an important role in CD46 binding.

Age-related declines in cell-mediated immunity (CMI) are associated with the incidence and severity of Herpes Zoster (HZ) infection. However, the level of Varicella-Zoster virus (VZV)-specific CMI associated with disease onset is unclear. This study aimed to examine factors associated with VZV-specific CMI, as measured by an interferon-gamma (IFN-γ) enzyme-linked immunospot (ELISPOT) assay, in a Japanese cohort. The study enrolled 365 subjects aged 60 years and over, all of whom were taking part in the Shozu Herpes Zoster (SHEZ) study and had undergone four sets of blood and intradermal reaction tests during a 3 year follow-up period. The VZV-specific immunity profile of each subject was assessed, and linear mixed effects models were constructed to analyze IFN-γ ELISPOT results in association with a combination of factors. The model that best explained the IFN-γ ELISPOT results was selected using the Akaike Information Criteria. The best-fit model consisted of age group as the only explanatory fixed-effect variable. The model showed that VZV-specific CMI, quantified as numbers of spots on the ELISPOT assay, among subjects aged 70-79 was on average 10.30 points lower than that among subjects aged 60-69. There was no statistically significant difference between subjects aged 70-79 and those aged 80-89. Age was the only factor significantly associated with the level of VZV-specific CMI, as measured by the IFN-γ ELISPOT assay. These results may represent an important step towards quantifying the relationship between VZV-specific CMI and the onset of HZ. J. Med. Virol. 89:313-317, 2017. © 2016 Wiley Periodicals, Inc.

Background In the USA, live attenuated varicella-zoster virus (VZV) vaccine is licensed for use in people 50 or older, to reduce the incidence and/or severity of herpes zoster. However, this vaccine is not yet available in Japan, and the immunity profile for VZV in older people has not been investigated in detail in Japan. Objectives The aim of this study was to conduct a detailed survey about the immunity profile for VZV in older people in Japan. Study design A panel of immunologic tests (skin test, ELISPOT, gpELISA, IAHA and NT) were used to analyze the immunity to VZV in the subjects. And an interview about zoster history was carried out with each of the subjects. Results Cellular immunity test (skin test and ELISPOT) results declined with increasing age; on the contrary, humoral immunity test (gpELISA, IAHA and NT) results increased with advancing age. In addition, strongly boosted humoral immunity was found in the subjects with zoster history, however relatively small increase was found in cellular immunity test results. Conclusions Cell-mediated immunity (CMI) to VZV decreased and humoral immunity increased with increasing age in this population.

Human herpesvirus 6 (HHV-6) glycoprotein Q1 (gQ1), a unique gene in HHV-6, forms a complex with glycoproteinH (gH) and gL, which is the viral ligand for its cellular receptor, CD46. However, whether gQ1 is essential for virus growth is unknown, because a system is lacking for making gene knockouts for HHV-6. Recently, bacterial artificial chromosome (BAC) and E. coli mutagenesis techniques have been applied to herpesvirus investigation. Here we successfully inserted the HHV-6A genome into a BAC, and obtained reconstituted infectious virus from the HHV-6A-containing BAC DNA. Using this system, we generated a gQ1 mutant virus genome, which failed to yield reconstituted infectious virus, whereas its revertant virus could be produced, indicating that the HHV-6 gQ1 gene is essential for virus growth. Therefore, we successfully applied BAC and E. coli mutagenesis techniques to the study of HHV-6, and discovered that HHV-6 gQ1 is an essential gene for virus growth.

human herpesvirus 6 (HHV-6) is the major causative agent of exanthem subitum which is one of popular diseases in infant, and establishes latent infections in adults of more than 90%. Recently, the encephalitis caused by reactivated- HHV-6 has been shown in patients after transplantation. In addition, the relationship HHV-6 and drug-induced hypersensitivity syndrome has also been reported. human herpesvirus 7 (HHV-7) was isolated from the stimulated-peripheral blood lymphocytes of a healthy individual, and also causes exanthema subitum. Both viruses are related viruses which belong to betaherpesvirus subfamily, and replicate and produce progeny viruses in T cells.

In this work, porous silica nanocapsules and silica nanospheres have been successfully fabricated by a novel combination of stabilizing condensation and dynamic self-assembly. When ethyl ether was used as a cosolvent, porous silica nanocapsules were obtained. In contrast, when 2-ethoxyethanol was used, silica porous nanospheres were produced. The silica nanostructures were characterized by small-angle X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, and nitrogen adsorption−desorption measurements. They had high Brunauer−Emmett−Teller specific surface areas and large pore volumes. The order of their pore structures increased with an increase of the corresponding cosolvent. In situ encapsulation of organic molecules into silica nanocapsules and their controlled release were further investigated by using pyrene as a typical example. As many dyes, drugs, etc. are organic molecules, the current approaches will doubtlessly open many possibilities...

Cell-membrane raft microdomains are important for successful infection by several viruses. However, their role in the cell-entry process of human herpesvirus-6 (HHV-6) is unknown. Here we tested whether HHV-6 requires cell-membrane rafts for its entry. When cell-membrane rafts were disrupted by cholesterol depletion, target-cell entry by HHV-6 was inhibited, although the virus bound normally to the cells. HHV-6 infectivity was partially rescued by adding exogenous cholesterol. Interestingly, the HHV-6 cellular receptor, CD46, was found in the rafts after virus attachment, but not in the rafts of uninfected cells, indicating that HHV-6 infection induces the re-location of its receptor into the rafts. Furthermore, glycoprotein Q1, part of a viral glycoprotein complex that binds CD46, was also associated with rafts immediately after infection. These data suggest that cellular-membrane lipid rafts are important in viral entry and that HHV-6 may enter the target cells via the rafts.

We identified two key amino acid residues within human CD134 (hCD134) that are required for its interaction with human herpesvirus 6B (HHV-6B) and for HHV-6B entry into cells. One of the residues (K79) allows access of the HHV-6B ligand to hCD134. Murine CD134 (mCD134) functioned as an HHV-6B receptor when these two amino acid residues were replaced with homologous human residues. This study identifies both the HHV-6B receptor-ligand interaction and the species-specific determinants of hCD134 essential for HHV-6B entry.

The etiology of Ramsay Hunt syndrome (Hunt syndrome) is reactivation of latent varicella-zoster virus (VZV) in the geniculate ganglion of the facial nerve, leading to neuritis. Although the mechanism of the VZV reactivation is unclear, one possibility is that the reactivation involves a low level of VZV-specific cell-mediated immunity (CMI). The aim of this study was to clarify the characteristics of the VZV-specific CMI in Hunt syndrome compared to that in Bell's palsy, and to obtain clues to its role in the development of Hunt syndrome.Prospective study.We determined the median spot numbers and examined VZV-specific CMI in patients with Hunt syndrome and with Bell's palsy using interferon-γ enzyme-linked immunospot (ELISPOT) assays. We analyzed the relationship between the value of VZV-specific CMI and days from disease onset.The median spot number in Hunt syndrome (87.3 spot-forming cells [SFCs]/4 × 10(5) peripheral blood mononuclear cells [PBMCs]) was higher than that in Bell's palsy (62.3 SFCs/4 × 10(5) PBMCs). Hunt syndrome showed a strong relationship between the ELISPOT count and days from onset (r = 0.65). Within the first 5 days from onset, no ELISPOT counts higher than 80 SFCs/4 × 10(5) PBMCs were observed. On the other hand, no correlation was observed between the ELISPOT count and days from onset in patients with Bell's palsy (r = -0.19).These results suggest that VZV-specific CMI in Hunt syndrome is low at disease onset and increases rapidly thereafter. Consequently, reduced VZV-specific CMI may play an important role in the reactivation of VZV in the facial nerve, leading to Hunt syndrome.

A novel in situ approach to mass fabrication of carbon nanotubes was reported. Composites of polypropylene (PP)/organomontmorillonite (OMMT)/nickel formate (NF) were prepared by mixing these components in a Brabender mixer at an elevated temperature. Chestnut-like carbon nanotube (CNT) spheres were in situ fabricated in high yields by heating the PP/OMMT/NF composites at 900 degrees C without adding any additional pre-synthesized nickel nanocatalysts. The products were studied by X-ray diffractometer (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, and N2 adsorption-desorption measurements. The results showed that nickel nanoparticles were in situ produced, which catalyzed the formation of multiwalled carbon nanotubes (MWNTs) in an autoclave-like microreactor formed by OMMT. These in situ formed nickel nanoparticles were found to be more catalytically active than pre-synthesized nickel nanocatalysts, resulting in higher yields of CNTs. The obtained CNT spheres have a high surface area, which makes them a good catalyst support. Loading of metal nanoparticles was preliminarily tried, and Pt nanoparticles of ca. 2.65 nm in size were successfully deposited on CNTs. The applications of these nanocatalysts in chemical reactions are currently being studied in our laboratory.

Human herpesvirus 6 (HHV-6) is a T-lymphotrophic virus belongs to the genus Roseolovirus within the beta herpesvirus subfamily. The U20-U24 gene cluster is unique to Roseoloviruses; however, both their function and whether they are essential for virus growth is unknown. Recently, bacterial artificial chromosome (BAC) techniques have been used to investigate HHV-6A. This study describes generation of a virus genome lacking U21-U24 (HHV-6ABACΔU21-24) and shows that infectious virus particles can be reconstituted from this BAC DNA. Our data indicate that the HHV-6 U21-U24 gene cluster is dispensable for virus propagation.

Based on genetic and antigenic differences and on their cell tropism, human herpes virus-6 (HHV-6) has been classified into two variants, HHV-6A and HHV-6B. Recently, these variants were re-classified as two different species. The HHV-6A glycoprotein complex, gH/gL/gQ1/gQ2 binds to its cellular receptor, CD46; however, the corresponding complex in HHV-6B rarely binds to CD46. To determine which viral molecules in the glycoprotein complex determine HHV-6A-CD46 binding, each molecule of the HHV-6A complex (i.e., gH, gL, gQ1, or gQ2) was replaced with the corresponding HHV-6B molecule, and the ability of the replaced protein to be incorporated into the complex and the ability of the complex to bind CD46 were examined. It was found that when all four glycoproteins were expressed, they were able to form a tetrameric complex. However, a complex formed by HHV-6A gH/gL/gQ1/gQ2 complexes replaced with HHV-6B gQ1 or gQ2 scarcely bind CD46, whereas HHV-6A complexes in which gH or gL was replaced with the HHV-6B molecules did bind it. These results indicate that HHV-6A gQ1 and gQ2 play an important role in CD46 binding.

Human herpesvirus-6B (HHV-6B) is a T lymphotropic β-herpesvirus that is clearly distinct from human herpesvirus-6A (HHV-6A) according to molecular biological features. The International Committee on Taxonomy of Viruses recently classified HHV-6B as a separate species. The primary HHV-6B infection causes exanthem subitum and is sometimes associated with severe encephalopathy. More than 90% of the general population is infected with HHV-6B during childhood, and the virus remains throughout life as a latent infection. HHV-6B reactivation causes encephalitis in immunosuppressed patients. The cellular receptor for HHV-6A entry was identified as human CD46, but the receptor for HHV-6B has not been clear. Here we found that CD134, a member of the TNF receptor superfamily, functions as a specific entry receptor for HHV-6B. A T-cell line that is normally nonpermissive for HHV-6B infection became highly susceptible to infection when CD134 was overexpressed. CD134 was down-regulated in HHV-6B–infected T cells. Soluble CD134 interacted with the HHV-6B glycoprotein complex that serves as a viral ligand for cellular receptor, which inhibited HHV-6B but not HHV-6A infection in target cells. The identification of CD134 as an HHV-6B specific entry receptor provides important insight into understanding HHV-6B entry and its pathogenesis.

Human herpesvirus 6 (HHV-6) is a T-cell-tropic betaherpesvirus. HHV-6 can be classified into two variants, HHV-6 variant A (HHV-6A) and HHV-6B, based on genetic, antigenic, and cell tropisms, although the homology of their entire genomic sequences is nearly 90%. The HHV-6A glycoprotein complex gH/gL/gQ1/gQ2 is a viral ligand that binds to the cellular receptor human CD46. Because gH has 94.3% amino acid identity between the variants, here we examined whether gH from one variant could complement its loss in the other. Recently, we successfully reconstituted HHV-6A from its cloned genome in a bacterial artificial chromosome (BAC) (rHHV-6ABAC). Using this system, we constructed HHV-6ABAC DNA containing the HHV-6B gH (BgH) gene instead of the HHV-6A gH (AgH) gene in Escherichia coli . Recombinant HHV-6ABAC expressing BgH (rHHV-6ABAC-BgH) was successfully reconstituted. In addition, a monoclonal antibody that blocks HHV-6B but not HHV-6A infection neutralized rHHV-6ABAC-BgH but not rHHV-6ABAC. These results indicate that HHV-6B gH can complement the function of HHV-6A gH in the viral infectious cycle.

Human herpesvirus 6 (HHV-6) is a T cell-tropic betaherpesvirus. HHV-6 can be classified into two variants, HHV-6A and HHV-6B, based on differences in their genetic, antigenic, and growth characteristics and cell tropisms. The function of HHV-6B should be analyzed more in its life cycle, as more than 90% of people have the antibodies for HHV-6B but not HHV-6A. It has been shown that the cellular receptor for HHV-6A is human CD46 and that the viral ligand for CD46 is the envelope glycoprotein complex gH/gL/gQ1/gQ2; however, the receptor-ligand pair used by HHV-6B is still unknown. In this study, to identify the glycoprotein(s) important for HHV-6B entry, we generated monoclonal antibodies (MAbs) that inhibit infection by HHV-6B. Most of these MAbs were found to recognize gQ1, indicating that HHV-6B gQ1 is critical for virus entry. Interestingly, the recognition of gQ1 by the neutralizing MAb was enhanced by coexpression with gQ2. Moreover, gQ1 deletion or point mutants that are not recognized by the MAb could nonetheless associate with gQ2, indicating that although the MAb recognized the conformational epitope of gQ1 exposed by the gQ2 interaction, this epitope was not related to the gQ2 binding domain. Our study shows that HHV-6B gQ1 is likely a ligand for the HHV-6B receptor, and the recognition site for this MAb will be a promising target for antiviral agents.

Human herpesvirus 6 (HHV-6) is a T-cell-tropic betaherpesvirus. A glycoprotein (g) complex that is unique to HHV-6, gH/gL/gQ1/gQ2, is a viral ligand for its cellular receptor, human CD46. However, whether complex formation or one component of the complex is required for CD46 binding and how the complex is transported in cells are open questions. Furthermore, in HHV-6-infected cells the gQ1 protein modified with N-linked glycans is expressed in two forms with different molecular masses: an 80-kDa form (gQ1-80K) and a 74-kDa form (gQ1-74K). Only gQ1-80K, but not gQ1-74K, forms the complex with gQ2, gH, and gL, and this four-component complex is incorporated into mature virions. Here, we characterized the molecular context leading to the maturation of gQ1 by expressing combinations of the individual gH/gL/gQ1/gQ2 components in 293T cells. Surprisingly, only when all four molecules were expressed was a substantial amount of gQ1-80K detected, indicating that all three of the other molecules (gQ2, gH, and gL) were necessary and sufficient for gQ1 maturation. We also found that only the tetrameric complex, and not its subsets, binds to CD46. Finally, a gQ2-null virus constructed in the BAC (bacterial artificial chromosome) system could not be reconstituted, indicating that gQ2 is essential for virus growth. These results show that gH, gL, gQ1, and gQ2 are all essential for the trafficking and proper folding of the gH/gL/gQ1/gQ2 complex and, thus, for HHV-6 infection.

In general, enveloped viruses are highly dependent on their lipid envelope for entry into host cells. Here, we demonstrated that during the course of virus maturation, a significant proportion of human herpesvirus 6 (HHV-6) envelope proteins were selectively concentrated in the detergent-resistant glycosphingolipid- and cholesterol-rich membranes (rafts) in HHV-6-infected cells. In addition, the ganglioside GM1, which is known to partition preferentially into lipid rafts, was detected in purified virions, along with viral envelope glycoproteins, gH, gL, gB, gQ1, gQ2 and gO indicating that at least one raft component was included in the viral particle during the assembly process.

Balo's concentric sclerosis (BCS) is a rare primary demyelinating disease of central nervous system (CNS) and is considered to be a variant of multiple sclerosis (MS). It is characterized by a severe, rapidly evolving course with CNS lesions consisting of concentric rings of demyelination alternating with myelination in the white matter. We report a patient with BCS from mainland China diagnosed on magnetic resonance imaging (MRI) findings. In addition to two contrast enhanced open ring lesions. MRI also showed multiple small white matter lesions in both the hemispheres. The patient had a good response to corticosteroids and had a benign prognosis during a follow-up period of two years.