Bacteriophages and their applications in the diagnosis and treatment of hepatitis B virus infection

Hepatitis B virus(HBV) infection is a major global health challenge leading to serious disorders such as cirrhosis and hepatocellular carcinoma. Currently, there exist various diagnostic and therapeutic approaches for HBV infection. However, prevalence and hazardous effects of chronic viral infection heighten the need to develop novel methodologies for the detection and treatment of this infection. Bacteriophages, viruses that specifically infect bacterial cells, with a long-established tradition in molecular biology and biotechnology have recently been introduced as novel tools for the prevention, diagnosis and treatment of HBV infection. Bacteriophages, due to tremendous genetic flexibility, represent potential to undergo a huge variety of surface modifications. This property has been the rationale behind introduction of phage display concept. This powerful approach, together with combinatorial chemistry, has shaped the concept of phage display libraries with diverse applications for the detection and therapy of HBV infection. This review aims to offer an insightful overview of the potential of bacteriophages in the development of helpful prophylactic(vaccine design), diagnostic and therapeutic strategies for HBV infection thereby providing new perspec-tives to the growing field of bacteriophage researches directing towards HBV infection.

Bacteriophages and development of nanomaterials for neural regeneration

Bacteriophages （phages） are viruses that infect bacterial cells and hijack the metabolism of the host cells for replication and amplification of their genetic information. These bacterial viruses are known to be the most numerous life forms on earth. Recent metagenomic analyses have revealed the vast untapped diversity of bacteriophages reinforcing the idea that our current knowledge on the phage world indicates only the tip of the iceberg （Clark, 2012）. The discovery of bacteriophages dramatically expanded the scope of applications of viruses in biotechnology and biomedicine.

Clinical, virologic and phylogenetic features of hepatitis B infection in Iranian patients

AIM： To characterize the clinical, serologic and virologic features of hepatitis B virus （HBV） infection in Iranian patients with different stages of liver disease.METHODS： Sixty two patients comprising of 12 inactive carriers, 30 chronic hepatitis patients, 13 patients with liver cirrhosis and 7 patients with hepatocellular carcinoma （HCC） were enrolled in the study. The HBV S, C and basal core promoter （BCP） regions were amplified and sequenced, and the clinical, serologic, phylogenetic and virologic characteristics were investigated.RESULTS： The study group consisted of 16 HBeAgpositive and 46 HBeAg-negative patients. Anti-HBepositive patients were older and had higher levels of ALT, ASL and bilirubin compared to HBeAg-positive patients. Phylogenetic analysis revealed that all patients were infected with genotype D （mostly ayw2）. The G1896A precore （PC） mutant was detected in 58.1% patients. HBeAg-negative patients showed a higher rate of PC mutant compared to HBeAg-positive patients （2,2 = 9.682, P = 0.003）. The majority of patients with HCC were HBeAg-negative and were infected with PC mutant variants. There was no significant difference in the occurrence of BCP mutation between the two groups, while the rate of BCP plus PC mutants was higher in HBeAg-negative patients （2,2 = 4.308, P = 0.04）. In the HBV S region, the genetic variability was low, and the marked substitution was P120T/S, with a rate of 9.7% （n = 6）.CONCLUSION： In conclusion, HBV/D is the predominant genotype in Iran, and the nucleotide variability in the BCP and PC regions may play a role in HBV disease outcome in HBeAg-negative patients.