title: Enhancement of CTLs induced by DCs loaded with ubiquitinated hepatitis B virus core antigen.
abstract: OBJECTIVE
  To investigate whether hepatitis B virus (HBV) could induce a hepatitis B virus core antigen (HBcAg)-specific cytotoxic T lymphocyte (CTL) response in vitro by dendritic cells (DCs) transduced with lentiviral vector-encoding ubiquitinated hepatitis B virus core antigen (LV-Ub-HBcAg).
  
  
  METHODS
  Recombinant LV-Ub-HBcAg were transfected into highly susceptible 293 T cells to obtain high virus titres. Bone marrow-derived DCs isolated from BALB/c mice were cultured with recombinant granulocyte-macrophage colony-stimulating factor and recombinant interleukin (IL)-4. LV-Ub-HBcAg, lentiviral vector-encoding hepatitis B virus core antigen (LV-HBcAg), lentiviral vector (LV) or lipopolysaccharide were added to induce DC maturation, and the DC phenotypes were analyzed by flow cytometry. The level of IL-12 in the supernatant was detected by enzyme-linked immunosorbent assay (ELISA). T lymphocytes were proliferated using Cell Counting Kit-8. DCs were cultured and induced to mature using different LVs, and co-cultured with allogeneic T cells to detect the secretion levels of IL-2, IL-4, IL-10 and interferon-γ in the supernatants of T cells by ELISA. Intracellular cytokines of proliferative T cells were analyzed by flow cytometry, and specific CTL activity was measured by a lactate dehydrogenase release assay.
  
  
  RESULTS
  LV-Ub-HBcAg-induced DCs secreted more IL-12 and upregulated the expression of CD80, CD86 and major histocompatibility class II. DCs sensitised by different LVs effectively promoted cytokine secretion; the levels of IL-2 and interferon-γ induced by LV-Ub-HBcAg were higher than those induced by LV-HBcAg. Compared with LV-HBcAg-transduced DCs, LV-Ub-HBcAg-transduced DCs more efficiently stimulated the proliferation of T lymphocytes and generated HBcAg-specific cytotoxic T lymphocytes.
  
  
  CONCLUSIONS
  LV-Ub-HBcAg effectively induced DC maturation. The mature DCs efficiently induced T cell polarisation to Th1 and generated HBcAg-specific CTLs.
authors.affiliation: Department of Infectious Diseases, Sixth People's Hospital Affiliated to Shanghai Jiaotong University, Shanghai 200233, China.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Chen
authors.forename: Yong-Sheng
authors.initials: YS
authors.lastname: Yu
authors.forename: Xiao-Hua
authors.initials: XH
authors.lastname: Chen
authors.forename: Hong-Hong
authors.initials: HH
authors.lastname: Liu
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Zang
authors.forename: Zheng-Hao
authors.initials: ZH
authors.lastname: Tang
mesh_terms: D000818:Animals; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology*; D005822:Genetic Vectors / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006512:Hepatitis B Core Antigens / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016130:Immunophenotyping; D018664:Interleukin-12 / Q000276:immunology; D016086:Lentivirus / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*; D054875:Ubiquitination
chemical_list: D006512:Hepatitis B Core Antigens; D018664:Interleukin-12