Recent advances in molecular diagnostics of hepatitis B virus

Abstract

Hepatitis B virus (HBV) is one of the important global health problems today. Infection with HBV can lead to a variety of clinical manifestations including severe hepatic complications like liver cirrhosis and hepatocellular carcinoma. Presently, routine HBV screening and diagnosis is primarily based on the immuno-detection of HBV surface antigen (HBsAg). However, identification of HBV DNA positive cases, who do not have detectable HBsAg has greatly encouraged the use of nucleic acid amplification based assays, that are highly sensitive, specific and are to some extent tolerant to sequence variation. In the last few years, the field of HBV molecular diagnostics has evolved rapidly with advancements in the molecular biology tools, such as polymerase chain reaction (PCR) and real-time PCR. Recently, apart of PCR based amplification methods, a number of isothermal amplification assays, such as loop mediated isothermal amplification, transcription mediated amplification, ligase chain reaction, and rolling circle amplification have been utilized for HBV diagnosis. These assays also offer options for real time detection and integration into biosensing devices. In this manuscript, we review the molecular technologies that are presently available for HBV diagnostics, with special emphasis on isothermal amplification based technologies. We have also included the recent trends in the development of biosensors and use of next generation sequencing technologies for HBV.

Keywords: Hepatitis B virus, Polymerase chain reaction, Isothermal amplification, Real time polymerase chain reaction, Biosensors, Next generation sequencing

Core tip: In the past decades, introduction of molecular biology tools such as polymerase chain reaction (PCR) has entirely revolutionized the field of hepatitis B virus (HBV) diagnosis by allowing sensitive and specific detection of the virus in body fluids. In the recent years a number of isothermal nucleic acid amplification have also evolved, that provide certain advantages over PCR. These isothermal amplification techniques are comparatively sensitive, specific, require less instrumentation and automation. This manuscript reviews the advantages/disadvantages of prevailing isothermal technologies to serve as an assay selection guide for the readers, working in the field of HBV molecular diagnostics.