Mutations in Pol gene of hepatitis B virus in patients with chronic hepatitis B before and after therapy with nucleoside/nucleotide analogues

The Removal of HBV in Plasma by Extracorporeal Immunoadsorption from Plasma: A Potential Therapy of Hepatitis B Patients

Objective

To establish a novel HBV specific immunoadsorbent for the removing of HBV particles.

Methods

The anti-HBsAg monoclonal antibody was immobilized on sepharose beads to produce a sepharose anti-HBs column. Then the immunoadsorbent was evaluated and characterized by scanning electron microscopy. In addition, time-dependent effects of the eradication capacity of anti-HBsAg functionalized sepharose beads against HBV were investigated.

Results

Proposed immunoadsorbents exhibited a favorable biocompatibility as well as specificity. With the optimized recycle time, the decontamination performance of HBV particles and quantity of HBsAg were assessed either by real-time quantitative PCR or ELISA, which showed that the immunoadsorbent could remove approximately 90% of the HBV and 90% of the HBsAg from human plasma samples.

Conclusions

All these results indicated that the novel immunoadsorbent could effectively remove HBV particles and likely serve as a novel therapy option or at least supplementary for the treatment regimen of HBV.

Relationship between pre-existing resistance mutations and HBV genotype in patients with HBV related liver cirrhosis

AIM

To investigate the relationship between hepatitis B virus (HBV)-related drug resistance mutations and HBV genotype in patients with HBV-related liver cirrhosis (LC).

METHODS

Serum samples were collected from 112 patients with HBV-related LC who did not receive prior anti-viral treatment. HBV reverse transcriptase regions were amplified by PCR, and PCR products were directly sequenced.

RESULTS

Among 112 HBV-related LC patients, 13 (11.61%, 13/112) had lamivudine resistance associated mutations, 15 (13.39%, 15/112) had adefovir resistance associated mutations, and 1 had mutations associated with both lamivudine and adefovir resistance. All of these resistance mutations occurred in patients infected with HBV genotype C, and there was no mutation in patients infected with HBV genotype B.

CONCLUSION

Adefovir/lamivudine resistance associated mutations exist in patients with HBV-related LC, and the mutations are related to HBV genotype. Compared with patients infected with HBV genotype B, those infected with HBV genotype C are prone to resistance mutations.

Inhibition of hepatitis B virus by the CRISPR/Cas9 system via targeting the conserved regions of the viral genome

Hepatitis B virus (HBV) remains a global health threat as chronic HBV infection may lead to liver cirrhosis or cancer. Current antiviral therapies with nucleoside analogues can inhibit the replication of HBV, but do not disrupt the already existing HBV covalently closed circular DNA. The newly developed CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated 9) system is a powerful tool to target cellular genome DNA for gene editing. In order to investigate the possibility of using the CRISPR/Cas9 system to disrupt the HBV DNA templates, we designed eight guide RNAs (gRNAs) that targeted the conserved regions of different HBV genotypes, which could significantly inhibit HBV replication both in vitro and in vivo. Moreover, the HBV-specific gRNA/Cas9 system could inhibit the replication of HBV of different genotypes in cells, and the viral DNA was significantly reduced by a single gRNA/Cas9 system and cleared by a combination of different gRNA/Cas9 systems.