title: Immunizations with hepatitis B viral antigens and a TLR7/8 agonist adjuvant induce antigen-specific immune responses in HBV-transgenic mice.
abstract: BACKGROUND
  The capacity of toll-like receptor (TLR) 7/8 agonist-conjugated hepatitis B virus (HBV) proteins (HBV-Ag) to overcome established hepatitis B surface antigen (HBsAg)-specific immune tolerance was explored.
  
  
  METHODS
  A TLR7/8 agonist, CL097, was conjugated with alum-absorbed HBsAg and hepatitis B core antigen (HBcAg), as confirmed by ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF MS). Mice from two independently generated HBV-transgenic (HBV-Tg) colonies, C57BL/6J-TgN (AlblHBV) 44Bri/J mice and C57BL/6-HBV-1.3 genome-eq mice, were immunized with CL097-conjugated HBV-Ag every 2 weeks, four times.
  
  
  RESULTS
  After immunization, 8/11 (72.7%) of the AlblHBV mice and 10/13 (76.9%) of the HBV-1.3 genome-eq mice generated serum detectable antibodies against HBsAg (anti-HBs). HBsAg-specific interferon gamma (IFN-γ)-producing CD4(+) and CD8(+) T-cells were detected in splenocytes from these mice. Naïve normal mice receiving splenocytes from the mice immunized with CL097-conjugated HBV-Ag generated immediate recall immune responses, e.g., the mice that received CD4(+)CD25(+)-depleted splenocytes generated anti-HBs on day 3 after HBsAg challenge while those receiving cells from sham-immunized mice did not.
  
  
  CONCLUSIONS
  Immunization with CL097-conjugated HBV-Ag reversed immune tolerance in HBV-Tg mice and induced antigen-specific immune responses. TLR7/8 agonists appear to be potent adjuvants for the induction of antigen-specific Th1 responses in an immune tolerant state.
authors.affiliation: State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Beijing 100021, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Beijing 100021, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Beijing 100021, China.
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Yuetao
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Pathology Department, Cancer Institute/Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Shangmei
authors.initials: S
authors.lastname: Liu
authors.affiliation: Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
authors.forename: Zhongmei
authors.initials: Z
authors.lastname: Zou
authors.affiliation: Departments of Oncological Sciences and Surgery, Mount Sinai School of Medicine, New York, New York, USA.
authors.forename: Shu-Hsia
authors.initials: SH
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Beijing 100021, China. Electronic address: quchf@cicams.ac.cn.
authors.forename: Chunfeng
authors.initials: C
authors.lastname: Qu
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D006509:Hepatitis B / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000097:blood; D006512:Hepatitis B Core Antigens / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D006515:Hepatitis B virus / Q000276:immunology; D007093:Imidazoles / Q000494:pharmacology*; D007108:Immune Tolerance / Q000187:drug effects*; D008297:Male; D008562:Membrane Glycoproteins / Q000819:agonists*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011804:Quinolines / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000276:immunology; D051199:Toll-Like Receptor 7 / Q000819:agonists*; D051200:Toll-Like Receptor 8 / Q000819:agonists*; D014611:Vaccination
chemical_list: D000276:Adjuvants, Immunologic; C547051:CL097 compound; D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D007093:Imidazoles; D008562:Membrane Glycoproteins; D011804:Quinolines; C552579:TLR8 protein, mouse; C477038:Tlr7 protein, mouse; D051199:Toll-Like Receptor 7; D051200:Toll-Like Receptor 8
keywords: Antigen-specific Th1 responses; Chronic hepatitis B virus infection; Immune tolerant state; Toll-like receptor 7/8 agonists