Purification and
Characterization of Recombinant Hepatitis B Virus Surface Antigen SS1 Expressed
in Pichia pastoris
YANG Jian-Ying, JIN Jing, KONG Yu-Ying, WEI Jun, ZHANG
Zu-Chuan, LI Guang-Di, WANG Yuan*
( Shanghai Institute of Biochemistry, the Chinese Academy of Sciences,
Shanghai 200031, China )
YUAN Han-Ying, LI Yu-Yang
( Institute of Genetics, Fudan University, Shanghai 200433, China
)
Abstract The
purification of recombinant hepatitis B surface antigen, SS1 protein, expressed
in Pichia pastoris, and the investigation of its physiochemical
characters and immunogenicity were described here. Employing McAb
immunoaffinity chromatography, this protein was purified to purity of 95%. The
results of ELISA and Western blotting showed good antigenicity of this purified
SS1 protein. CsCl gradient centrifugation and electron microscopy assay proved
that this purified protein could be assembled into particles similar to the HBV
subviral particles. Strong antibody responses against both the HBs and PreS1
epitopes were induced in BALB/c mice immunized with this purified protein. The
simultaneous injection of a CpG adjuvant induced a Th1-like immune response
against both the HBs and PreS1 epitopes.
Key words hepatitis B virus surface antigen；PreS1；Pichia pastoris；purification and
characterization；CpG
*Corresponding author：Tel,86-21-64374430；Fax, 86-21-64338357；
e-mail,[email protected]