title: Serum hepatitis B virus RNA is encapsidated pregenome RNA that may be associated with persistence of viral infection and rebound.
abstract: Hepatitis B virus (HBV) RNA in serum has recently been linked to efficacy and prognosis of chronic hepatitis B (CHB) treatment. This study explored the nature, origin, underlying mechanisms, and potential clinical significance of serum HBV RNA.
  
  
  
  The levels of HBV DNA and RNA were determined in the supernatant of induced HepAD38, HBV-expressing HepG2.2.15 cells and primary human hepatocytes (PHH), and in the serum of transgenic mice and CHB patients. NP-40 and proteinase K treatment, sucrose density gradient centrifugation, electron microscopy, northern blot, multiple identification PCRs and 5' rapid-amplification of cDNA ends were performed to identify the nature of serum HBV RNA.
  
  
  
  Although significantly lower than HBV DNA levels, abundant HBV RNA was present in the serum of CHB patients. A series of experiments demonstrated that serum HBV RNA was pregenome RNA (pgRNA) and present in virus-like particles. HBV pgRNA virion levels increased after blocking the reverse transcription activity of HBV DNA polymerase, and decreased after blocking the encapsidation of pgRNA. Furthermore, the presence of HBV pgRNA virion was associated with risk of viral rebound after discontinuation of nucleot(s)ide analogues (NAs) therapy in CHB patients.
  
  
  
  Serum HBV RNA was confirmed to be pgRNA present in virus-like particles. HBV pgRNA virions were produced from encapsidated particles in which the pgRNA was non- or partially reverse transcribed. Clinically, HBV pgRNA virion might be a potential biomarker for monitoring safe discontinuation of NA-therapy.
  
  
  
  HBV may have another virion form in which the nucleic acid is composed of RNA, not DNA. The level of HBV RNA virion in serum may be associated with risk of HBV viral rebound after withdrawal of treatment, and therefore, a potential predictive biomarker to monitor the safe discontinuation of nucleot(s)ide analogues-therapy.
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Xiangbo
authors.initials: X
authors.lastname: Huang
authors.affiliation: Assembly Biosciences, Inc., San Francisco, CA, USA.
authors.forename: G Renuka
authors.initials: GR
authors.lastname: Kumar
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Xiangmei
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Zeng
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Ruiyang
authors.initials: R
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Tong
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China.
authors.forename: Tianying
authors.initials: T
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: Assembly Biosciences, Inc., San Francisco, CA, USA.
authors.forename: Pao-Chen
authors.initials: PC
authors.lastname: Li
authors.affiliation: Assembly Biosciences, Inc., San Francisco, CA, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Assembly Biosciences, Inc., San Francisco, CA, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Colonno
authors.affiliation: Clinical Epidemiology and EBM Unit, Being Friendship Hospital, Capital Medical University, China.
authors.forename: Jidong
authors.initials: J
authors.lastname: Jia
authors.affiliation: Hepatology Unit and Key Laboratory for Organ Failure Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.
authors.forename: Jinlin
authors.initials: J
authors.lastname: Hou
authors.affiliation: The Pirbright Institute, Pirbright, UK.
authors.forename: Malcolm A
authors.initials: MA
authors.lastname: McCrae
authors.affiliation: Department of Infectious Diseases, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong Province, China. Electronic address: gaozl@21cn.com.
authors.forename: Zhiliang
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Department of Infectious Diseases, Institute of Viral Hepatitis, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China. Electronic address: renhong0531@vip.sina.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, China. Electronic address: nsxia@xmu.edu.cn.
authors.forename: Ningshao
authors.initials: N
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhuang
authors.affiliation: State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology & Infectious Disease Center, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China. Electronic address: lu.fengmin@hsc.pku.edu.cn.
authors.forename: Fengmin
authors.initials: F
authors.lastname: Lu
mesh_terms: D000818:Animals; D004279:DNA, Viral; D006515:Hepatitis B virus; D019694:Hepatitis B, Chronic; D006801:Humans; D051379:Mice; D017830:Octoxynol; D011092:Polyethylene Glycols; D012367:RNA, Viral
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D011092:Polyethylene Glycols; D017830:Octoxynol; C010615:Nonidet P-40
keywords: HBV pgRNA virion; Hepatitis B virus; Nucleot(s)ide analogues therapy