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Measurement of hepatitis B virus DNA in fresh versus processed dentin from chronically infected patients.

ABSTRACT: BACKGROUND:Demineralized dentin matrix (DDM) is commonly used as a bone-graft substitute. This study measured and compared human hepatitis B viruses (HBV) DNA in fresh dentin to that of dentin processed into DDM extracted during dental treatment from HBV-infected patients. The hypothesis was that the processing procedure for DDM would inactivate or eliminate HBV in the dentin matrix obtained from infected patients. METHODS:Dentin from eighteen HBV-infected patients was collected and each dentin specimen was divided into two fragments. One fragment was used before processing as fresh dentin (control group) and the other was processed into DDM (experimental group). DNA was extracted and purified from each fresh and processed dentin specimen and the HBV DNA copy number quantitated by real time polymerase chain reaction. The HBV DNA copy number in the fresh dentin specimens were compared relative to serologic test results. The second parameter was to evaluate the effectiveness of the processing procedure (defatting, demineralization, freeze-drying, and sterilization) to inactivate or eliminate HBV by comparing the DNA copy number in the processed DDM with that in the matched fresh dentin specimens. All results were analyzed using Mann-Whitney U test to compare numerical measurements between groups and differences were considered statistically significant at P-values less than 0.05. RESULTS:The presence of HBV DNA was detected in 55.56% (10/18) of the fresh dentin specimens. For the ten HBV DNA-positive fresh dentin specimens, HBV DNA was detected in two (20%) of the matched processed dentin specimens. The copy number of HBV DNA in the two positive processed dentin specimens was 1.79 and 4.03, which were statistically lower than that of the fresh dentin specimens (P?=?0.0167). CONCLUSIONS:The results from this study suggested that fresh dentin may be a carrier of HBV and that the procedure used to generate DDM extensively reduced the levels of HBV DNA. Further studies are needed to evaluate the infectivity of HBV in processed dentin.

SUBMITTER: Um I

PROVIDER: S-EPMC6292124 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Measurement of hepatitis B virus DNA in fresh versus processed dentin from chronically infected patients.

Um Inwoong I Choi Sungweon S Kim Youngkyun Y Pang Kangmi K Lee Jongho J Lee Minsun M Kim Bongju B

Journal of translational medicine 20181212 1

<h4>Background</h4>Demineralized dentin matrix (DDM) is commonly used as a bone-graft substitute. This study measured and compared human hepatitis B viruses (HBV) DNA in fresh dentin to that of dentin processed into DDM extracted during dental treatment from HBV-infected patients. The hypothesis was that the processing procedure for DDM would inactivate or eliminate HBV in the dentin matrix obtained from infected patients.<h4>Methods</h4>Dentin from eighteen HBV-infected patients was collected a ...[more]

PMID: 30541555

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Project description:Covalently closed circular DNA (cccDNA) forms the basis for replication and persistence of hepatitis B virus (HBV) in the chronically infected liver. We have previously shown that viral transcription is subject to regulation by posttranslational modifications (PTMs) of histone proteins bound to cccDNA through analysis of de novo HBV-infected cell lines. We now report the successful adaptation of this chromatin immunoprecipitation sequencing (ChIPseq) approach for analysis of fine-needle patient liver biopsy specimens to investigate the role of histone PTMs in chronically HBV-infected patients. Using 18 specimens from patients in different stages of chronic HBV infection, our work shows that the profile of histone PTMs in chronic infection is more nuanced than previously observed in in vitro models of acute infection. In line with our previous findings, we find that the majority of HBV-derived sequences are associated with the activating histone PTM H3K4me3. However, we show a striking interpatient variability of its deposition in this patient cohort correlated with viral transcription and patient HBV early antigen (HBeAg) status. Unexpectedly, we detected deposition of the classical inhibitory histone PTM H3K9me3 on HBV-DNA in around half of the patient biopsy specimens, which could not be linked to reduced levels of viral transcripts. Our results show that current in vitro models are unable to fully recapitulate the complex epigenetic landscape of chronic HBV infection observed in vivo and demonstrate that fine-needle liver biopsy specimens can provide sufficient material to further investigate the interaction of viral and host proteins on HBV-DNA.IMPORTANCE Hepatitis B virus (HBV) is a major global health concern, chronically infecting millions of patients and contributing to a rising burden of liver disease. The viral genome forms the basis for chronic infection and has been shown to be subject to regulation by epigenetic mechanisms, such as posttranslational modification of histone proteins. Here, we confirm and expand on previous results by adapting a high-resolution technique for analysis of histone modifications for use with patient-derived fine-needle liver biopsy specimens. Our work highlights that the situation in vivo is more complex than predicted by current in vitro models, for example, by suggesting a novel, noncanonical role of the histone modification H3K9me3 in the HBV life cycle. Importantly, enabling the use of fine-needle liver biopsy specimens for such high-resolution analyses may facilitate further research into the epigenetic regulation of the HBV genome.

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Dataset Information

Measurement of hepatitis B virus DNA in fresh versus processed dentin from chronically infected patients.

Publications

Measurement of hepatitis B virus DNA in fresh versus processed dentin from chronically infected patients.

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