title: Immunization of Mice by BCG Formulated HCV Core Protein Elicited Higher Th1-Oriented Responses Compared to Pluronic-F127 Copolymer.
abstract: BACKGROUND
  A supreme vaccine for Hepatitis C virus (HCV) infection should elicit strong Th1-oriented cellular responses. In the absence of a Th1-specific adjuvant, immunizations by protein antigens generally induce Th2-type and weak cellular responses.
  
  
  OBJECTIVE
  To evaluate the adjuvant effect of BCG in comparison with nonionic copolymer-Pluronic F127 (F127) as a classic adjuvant in the formulation of HCV core protein (HCVcp) as a candidate vaccine for induction of Th1 immune responses.
  
  
  METHODS
  Expression of N-terminally His-Tagged HCVcp (1-122) by pIVEX2.4a-core vector harboring the corresponding gene under the control of arabinose-inducible (araBAD) promoter was achieved in BL21-AI strain of E.coli and purified through application of nitrilotriacetic acid (Ni-NTA) chromatography. Mice were immunized subcutaneously (s.c.) in base of the tail with 100 μl of immunogen (F127+HCVcp or BCG+HCVcp; 5 μgHCVcp/mouse/dose) or control formulations (PBS, BCG, F127) at weeks 0, 3, 6. Total and subtypes of IgG, as well as cellular immune responses (Proliferation, In vivo CTL and IFN-γ/IL-4 ELISpot assays against a strong and dominant H2-d restricted, CD8+-epitopic peptide, core 39-48; RRGPRLGVRA of HCVcp) were compared in each group of immunized animals.
  
  
  RESULTS
  Expression and purification of core protein around the expected size (21 kDa) was confirmed by Western blotting. The HCVcp + BCG vaccinated mice showed significantly higher lymphocyte proliferation and IFN-γ production but lower levels of cell lysis (45% versus 62% in CTL assay) than the HCVcp+F127 immunized animals. "Besides, total anti-core IgG and IgG1 levels were significantly higher in HCVcp + F127 immunized mice as compared to HCVcp + BCG vaccinated animals, indicating relatively higher efficacy of F127 for the stimulation of humoral and Th2-oriented immune responses".
  
  
  CONCLUSIONS
  Results showed that HCVcp + BCG induced a moderate CTL and mixed Th1/Th2 immune responses with higher levels of cell proliferation and IFN-γ secretion, indicating that BCG may have a better outcome when formulated in HCVcp-based subunit vaccines.
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Yazdanian
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Arash
authors.initials: A
authors.lastname: Memarnejadian
authors.affiliation: Virology Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mahdavi
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Seyed Mehdi
authors.initials: SM
authors.lastname: Sadat
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Motevali
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Rouhollah
authors.initials: R
authors.lastname: Vahabpour
authors.affiliation: BCG Research Center, Karaj Research and Production Complex, Pasteur Institute of Iran, Karaj, IR Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Khanahmad
authors.affiliation: Microbiology Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Seyed Davar
authors.initials: SD
authors.lastname: Siadat
authors.affiliation: Hepatitis and AIDS Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Aghasadeghi
authors.affiliation: Virology Department, Pasteur Institute of Iran, Tehran, IR Iran.
authors.forename: Farzin
authors.initials: F
authors.lastname: Roohvand
keywords: Adjuvant; Bacillus Calmette-Guerin (BCG); HCV; PluronicF127