Unimpaired immunogenicity of yeast-expressed hepatitis B surface antigen stored at elevated temperatures.
Global adoption of hepatitis B virus (HBV) vaccines has greatly reduced new HBV infections. Current HBV vaccines are liquid suspensions containing recombinant hepatitis B surface antigen (HBsAg) particles mixed with aluminum phosphate or aluminum hydroxide. Refrigeration (2-8°C) as recommended for vaccine transport and storage may be unachievable in certain HBV-prevalent developing countries or regions. In this study, we stored yeast-expressed HBsAg and aluminum hydroxide separately at the standard (4°C) and elevated temperature (25, 37, or 45°C) for 14, 23, and 30 days, then mixed them and used the mixture to vaccinate mice with a prime-boost program. The antisera from all the vaccinated mice successfully inhibited HBV infection of HepG2 cells stably expressing HBV receptor sodium taurocholate cotransporting polypeptide. Furthermore, no serum HBsAg was detected in vaccinated mice on Day 1 post-hydrodynamic injection (HDI) of an HBV replicon plasmid and onwards, accompanied with an increasing anti-HBsAg antibody (HBsAb) level. In contrast, serum HBsAg in phosphate-buffered saline (PBS)-injected mice peaked on Day 4 post-HDI and was cleared on Day 14 post-HDI, which coincided with appearance of HBsAb on Day 7 post-HDI, suggesting a typical HBV acute infection process. HBV DNA peaked on Day 4 post-HDI in vaccinated mice, its level significantly lower than that in PBS-injected mice on Day 7 post-HDI, and showed a higher clearance rate. Taken together, we conclude that storing recombinant HBsAg at 25, 37, or 45°C for 14-30 days does not impair its immunogenicity in mice.
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China.
Zhongliang
Z
Shen
School of Basic Medicine, Shanghai University of Medicine and Health Science, Shanghai 201206, China.
Yuliang
Y
Rao
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China.
Shuai
S
Tao
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China.
Mengjun
M
Luo
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China.
Lijun
L
Ming
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China.
Jing
J
Liu
Department of Preventive Dentistry, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200011, China panshaokun@foxmail.com yhxie@fudan.edu.cn.
Shaokun
S
Pan
Key Laboratory of Medical Molecular Virology (Ministry of Health and Ministry of Education), Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai 200031, China panshaokun@foxmail.com yhxie@fudan.edu.cn.
Youhua
Y
Xie
D000818:Animals; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D056945:Hep G2 Cells; D006514:Hepatitis B Surface Antigens / Q000235:genetics* / Q000276:immunology; D006515:Hepatitis B virus / Q000502:physiology; D006358:Hot Temperature; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D012441:Saccharomyces cerevisiae / Q000235:genetics*
D006514:Hepatitis B Surface Antigens
HBV vaccine; HBsAb; HBsAg; immunogenicity; storage temperature