Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Differences in the Likelihood of Acyclovir Resistance-Associated Mutations in the Thymidine Kinase Genes of Herpes Simplex Virus 1 and Varicella-Zoster Virus.

ABSTRACT: Acyclovir (ACV) resistance-associated mutations in two recombinant herpes simplex virus 1 (HSV-1) clones were compared. Recombinant HSV-1 lacking its thymidine kinase (TK) and expressing varicella-zoster virus (VZV) TK ectopically had no mutations in the VZV TK gene. In contrast, recombinant HSV-1 expressing HSV-1 TK ectopically harbored mutations in the HSV-1 TK gene. These results suggest that the relatively low frequency of ACV-resistant VZV is a consequence of the characteristics of the TK gene.

SUBMITTER: Fujii H

PROVIDER: S-EPMC6496055 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Differences in the Likelihood of Acyclovir Resistance-Associated Mutations in the Thymidine Kinase Genes of Herpes Simplex Virus 1 and Varicella-Zoster Virus.

Fujii Hikaru H Harada Shizuko S Yoshikawa Tomoki T Yamada Souichi S Omura Natsumi N Shibamura Miho M Inagaki Takuya T Kato Hirofumi H Fukushi Shuetsu S Saijo Masayuki M

Antimicrobial agents and chemotherapy 20190425 5

Acyclovir (ACV) resistance-associated mutations in two recombinant herpes simplex virus 1 (HSV-1) clones were compared. Recombinant HSV-1 lacking its thymidine kinase (TK) and expressing varicella-zoster virus (VZV) TK ectopically had no mutations in the VZV TK gene. In contrast, recombinant HSV-1 expressing HSV-1 TK ectopically harbored mutations in the HSV-1 TK gene. These results suggest that the relatively low frequency of ACV-resistant VZV is a consequence of the characteristics of the TK g ...[more]

PMID: 30858222

Similar Datasets

A rapid phenotypic assay for detection of acyclovir-resistant varicella-zoster virus with mutations in the thymidine kinase open reading frame.

Project description:Susceptibility assays by cell culture methods are time-consuming and are particularly difficult to perform with varicella-zoster virus (VZV). To overcome this limitation, we have adapted a functional test of the viral thymidine kinase (TK) in TK-deficient (tdk mutant) bacteria to detect ACV-resistant VZV in clinical samples. After PCR amplification, the complete viral TK open reading frame (ORF) is purified from PCR primers, digested with two restriction enzymes, and ligated in an oriented fashion into a bacterial expression vector. The ligation products are then used to transform tdk mutant bacteria. After transformation, an aliquot of the bacteria is plated onto a plate with minimal medium containing (i) ampicillin to select for plasmids carrying the viral TK ORF and (ii) isopropyl beta-D-thiogalactopyranoside (IPTG) to induce its expression. An identical aliquot of bacteria is also plated onto a medium containing, in addition to the components described above, 5-fluorodeoxyuridine (FUdR). Compared to the number of transformants on FUdR-free medium, the number of colonies carrying TK derived from susceptible strains was reduced by 86%, on average, in the presence of FUdR. In contrast, the number of transformants carrying TK from resistant strains with a mutant TK were reduced by only 4%, on average, on FUdR-containing plates. We have assessed the validity of this assay with cell culture isolates and several clinical samples including two cerebrospinal fluid samples from which no virus could be isolated. This colony reduction assay allowed the correct identification of the TK phenotype of each VZV isolate tested and can be completed within 3 days of receipt of the sample.

| S-EPMC89785 | biostudies-literature

Phenotypic and genetic characterization of thymidine kinase from clinical strains of varicella-zoster virus resistant to acyclovir.

Project description:Varicella-zoster virus (VZV) is a common herpesvirus responsible for disseminated or chronic infections in immunocompromised patients. Effective drugs such as acyclovir (ACV), famciclovir (prodrug of penciclovir), and foscarnet are available to treat these infections. Here we report the phenotypic and genetic characterization of four ACV-resistant VZV strains isolated from AIDS patients and transplant recipients. Sensitivity to six antiviral drugs was determined by an enzyme-linked immunosorbent assay, viral thymidine kinase (TK) activity was measured by comparing [(3)H]thymidine and 1-beta-D-arabinofuranosyl-[(3)H]thymine as substrates, and the TK gene open reading frame was sequenced. Three strains were found to be TK deficient, and the fourth was a mixed population composed of TK-positive and TK-deficient viruses. Each strain presented a unique TK gene mutation that could account for ACV resistance. In one strain, the deletion of two nucleotides at codon 215 induced a premature stop signal at codon 217. In another strain, a single nucleotide addition at codon 167 resulted in a premature stop signal at codon 206. In both other strains, we identified amino acid substitutions already described in other ACV-resistant VZV strains: either Glu-->Gly at residue 48 or Arg-->Gly at residue 143. According to our work and data previously reported on resistant VZV strains, there are three areas in the TK gene where 71% of the mutations described to date are located. These areas are putative candidates for a genotypic diagnosis of ACV resistance.

| S-EPMC89493 | biostudies-literature

Rapid detection of herpes simplex virus and varicella-zoster virus infections by real-time PCR.

Project description:The herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2) and varicella-zoster virus (VZV) can cause life-threatening infections of the central nervous system and lead to severe infections in immunocompromised subjects and newborns. In these cases, rapid diagnosis is crucial. We developed three different real-time PCR assays based on TaqMan chemistry for the LightCycler instrument to detect HSV-1, HSV-2, and VZV. When the TaqMan assays were compared to our in-house nested PCR assays, the test systems had equal sensitivities of <or=10 plasmid copies per assay. When clinical samples were investigated by TaqMan PCR to detect HSV-1, HSV-2, and VZV DNA, 95, 100, and 96% of the samples determined to be positive by nested PCR, respectively, were positive by the real-time PCR assays. The specificities of all PCR assays were almost 100%. Furthermore, the TaqMan PCR assays could be performed within 2.5 h, whereas nested PCR results were available after 9 h. In addition to offering more rapid results, the TaqMan PCR assays appear to be less expensive than nested PCR assays due to less hands-on time. In summary, TaqMan PCR is an excellent alternative to conventional nested PCR assays for the rapid detection of HSV-1, HSV-2, and VZV in clinical samples.

| S-EPMC153887 | biostudies-literature

Autophagic flux without a block differentiates varicella-zoster virus infection from herpes simplex virus infection.

Project description:Autophagy is a process by which misfolded and damaged proteins are sequestered into autophagosomes, before degradation in and recycling from lysosomes. We have extensively studied the role of autophagy in varicella-zoster virus (VZV) infection, and have observed that vesicular cells are filled with >100 autophagosomes that are easily detectable after immunolabeling for the LC3 protein. To confirm our hypothesis that increased autophagosome formation was not secondary to a block, we examined all conditions of VZV infection as well as carrying out two assessments of autophagic flux. We first investigated autophagy in human skin xenografts in the severe combined immunodeficiency (SCID) mouse model of VZV pathogenesis, and observed that autophagosomes were abundant in infected human skin tissues. We next investigated autophagy following infection with sonically prepared cell-free virus in cultured cells. Under these conditions, autophagy was detected in a majority of infected cells, but was much less than that seen after an infected-cell inoculum. In other words, inoculation with lower-titered cell-free virus did not reflect the level of stress to the VZV-infected cell that was seen after inoculation of human skin in the SCID mouse model or monolayers with higher-titered infected cells. Finally, we investigated VZV-induced autophagic flux by two different methods (radiolabeling proteins and a dual-colored LC3 plasmid); both showed no evidence of a block in autophagy. Overall, therefore, autophagy within a VZV-infected cell was remarkably different from autophagy within an HSV-infected cell, whose genome contains two modifiers of autophagy, ICP34.5 and US11, not present in VZV.

| S-EPMC4291665 | biostudies-literature

Variant Analysis of the Thymidine Kinase and DNA Polymerase Genes of Herpes Simplex Virus in Korea: Frequency of Acyclovir Resistance Mutations.

Project description:The thymidine kinase (TK) and DNA polymerase (pol) genes of the herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) are two important genes involved in antiviral resistance. We investigated the genetic polymorphisms of the HSV-TK and pol genes in clinical isolates from Korean HSV-infected patients using next-generation sequencing (NGS) for the first time in Korea. A total of 81 HSV-1 and 47 HSV-2 isolates were examined. NGS was used to amplify and sequence the TK and pol genes. Among the 81 HSV-1 isolates, 12 and 17 natural polymorphisms and 9 and 23 polymorphisms of unknown significance in TK and pol were found, respectively. Two HSV-1 isolates (2.5%) exhibited the E257K amino acid substitution in TK, associated with antiviral resistance. Out of 47 HSV-2 isolates, 8 natural polymorphisms were identified in TK, and 9 in pol, with 13 polymorphisms of unknown significance in TK and 10 in pol. No known resistance-related mutations were observed in HSV-2. These findings contribute to our understanding of the genetic variants associated with antiviral resistance in HSV-1 and HSV-2 in Korea, with frequencies of known antiviral resistance-related mutations of 2.5% and 0% in HSV-1 and HSV-2, respectively.

| S-EPMC10458183 | biostudies-literature

A genome-wide comparative evolutionary analysis of herpes simplex virus type 1 and varicella zoster virus.

Project description:Herpes simplex virus type 1 (HSV-1) and varicella zoster virus (VZV) are closely related viruses causing lifelong infections. They are typically associated with mucocutaneous or skin lesions, but may also cause severe neurological or ophthalmic diseases, possibly due to viral- and/or host-genetic factors. Although these viruses are well characterized, genome-wide evolutionary studies have hitherto only been presented for VZV. Here, we present a genome-wide study on HSV-1. We also compared the evolutionary characteristics of HSV-1 with those for VZV. We demonstrate that, in contrast to VZV for which only a few ancient recombination events have been suggested, all HSV-1 genomes contain mosaic patterns of segments with different evolutionary origins. Thus, recombination seems to occur extremely frequent for HSV-1. We conclude by proposing a timescale for HSV-1 evolution, and by discussing putative underlying mechanisms for why these otherwise biologically similar viruses have such striking evolutionary differences.

| S-EPMC3143153 | biostudies-literature

Association between sensitivity of viral thymidine kinase-associated acyclovir-resistant herpes simplex virus type 1 and virulence.

Project description:BackgroundAcyclovir (ACV)-resistant (ACVr) herpes simplex virus type 1 (HSV-1) infections are concern in immunocompromised patients. Most clinical ACVr HSV-1 isolates have mutations in the viral thymidine kinase (vTK) genes. The vTK-associated ACVr HSV-1 shows reduced virulence, but the association between the level of resistance and the virulence of the vTK-associated ACVr HSV-1 is still unclear.MethodsThe virulence in mice of 5 vTK-associated ACVr HSV-1 clones with a variety of ACV sensitivities, when inoculated through intracerebral and corneal routes, was evaluated in comparison with ACV-sensitive (ACVs) parent HSV-1 TAS.ResultsAlthough all the 5 ACVr HSV-1 clones and ACVs HSV-1 TAS showed a similar single-step growth capacity in vitro, the virulence of ACVr HSV-1 clones significantly decreased. A 50% lethal dose (LD50) of each clone was closely correlated with 50% inhibitory concentrations (IC50), demonstrating that the higher the ACV-sensitvity, the the higher the virulence among the ACVr clones. One of the ACVr HSV-1 clones with a relatively low IC50 value maintained similar virulence to that of the parent TAS. The infection in mice with ACVr HSV-1 due to a single amino acid substitution in vTK induced local diseases, keratitis and dermatitis, while vTK-deficient clone did not.ConclusionsA statistically significant correlation between the virulence and susceptibility to ACV among ACVr HSV-1 clones was demonstrated.

| S-EPMC5359899 | biostudies-literature

Pharmacokinetics and safety of famciclovir in children with herpes simplex or varicella-zoster virus infection.

Project description:Two multicenter, open-label, single-arm, two-phase studies evaluated single-dose pharmacokinetics and single- and multiple-dose safety of a pediatric oral famciclovir formulation (prodrug of penciclovir) in children aged 1 to 12 years with suspicion or evidence of herpes simplex virus (HSV) or varicella-zoster virus (VZV) infection. Pooled pharmacokinetic data were generated after single doses in 51 participants (approximately 12.5 mg/kg of body weight [BW] for children weighing < 40 kg and 500 mg for children weighing > or = 40 kg). The average systemic exposure to penciclovir was similar (6- to 12-year-olds) or slightly lower (1- to < 6-year-olds) than that in adults receiving a 500-mg dose of famciclovir (historical data). The apparent clearance of penciclovir increased with BW in a nonlinear manner, proportional to BW(0.696). An eight-step weight-based dosing regimen was developed to optimize exposure in smaller children and was used in the 7-day multiple-dose safety phases of both studies, which enrolled 100 patients with confirmed/suspected viral infections. Twenty-six of 47 (55.3%) HSV-infected patients who received famciclovir twice a day and 24 of 53 (45.3%) VZV-infected patients who received famciclovir three times a day experienced at least one adverse event. Most adverse events were gastrointestinal in nature. Exploratory analysis following 7-day famciclovir dosing regimen showed resolution of symptoms in most children with active HSV (19/21 [90.5%]) or VZV disease (49/53 [92.5%]). Famciclovir formulation (sprinkle capsules in OraSweet) was acceptable to participants/caregivers. In summary, we present a weight-adjusted dosing schedule for children that achieves systemic exposures similar to those for adults given the 500-mg dose.

| S-EPMC2681556 | biostudies-literature

Longitudinal study on oral shedding of herpes simplex virus 1 and varicella-zoster virus in individuals infected with HIV.

Project description:Primary herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV) infection leads to a life-long latent infection of ganglia innervating the oral mucosa. HSV-1 and VZV reactivation is more common in immunocompromised individuals and may result in viral shedding in saliva. We determined the kinetics and quantity of oral HSV-1 and VZV shedding in HSV-1 and VZV seropositive individuals infected with HIV and to assess whether HSV-1 shedding involves reactivation of the same strain intra-individually. HSV-1 and VZV shedding was determined by real-time PCR of sequential daily oral swabs (n?=?715) collected for a median period of 31 days from 22 individuals infected with HIV. HSV-1 was genotyped by sequencing the viral thymidine kinase gene. Herpesvirus shedding was detected in 18 of 22 participants. Shedding of HSV-1 occurred frequently, on 14.3% of days, whereas solely VZV shedding was very rare. Two participants shed VZV. The median HSV-1 load was higher compared to VZV. HSV-1 DNA positive swabs clustered into 34 shedding episodes with a median duration of 2 days. The prevalence, duration and viral load of herpesvirus shedding did not correlate with CD4 counts and HIV load. The genotypes of the HSV-1 viruses shed were identical between and within shedding episodes of the same person, but were different between individuals. One-third of the individuals shed an HSV-1 strain potentially refractory to acyclovir therapy. Compared to HSV-1, oral VZV shedding is rare in individuals infected with HIV. Recurrent oral HSV-1 shedding is likely due to reactivation of the same latent HSV-1 strain.

| S-EPMC4020591 | biostudies-literature

Distribution of herpes simplex virus type 1 and varicella zoster virus in ganglia of the human head and neck.

Project description:The distribution of the neurotropic alphaherpesviruses-herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) and varicella zoster virus (VZV)-was determined in autonomic and sensory ganglia of the head and neck obtained from formalin-fixed human cadavers. HSV-1 and VZV DNA were found in 18 of 58 and 16 of 58 trigeminal, 23 of 58 and 11 of 58 pterygopalatine, 25 of 60 and 14 of 60 ciliary, 25 of 48 and 11 of 48 geniculate, 15 of 50 and 8 of 50 otic, 14 of 47 and 4 of 47 submandibular, 18 of 58 and 10 of 58 superior cervical, and 12 of 36 and 1 of 36 nodose ganglia, respectively. HSV-2 was not detected at any site. Viral DNA positivity and location were independently distributed among autonomic and sensory ganglia of the human head and neck.

| S-EPMC2782560 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data