Objectives We aimed to estimate the impact of the national hepatitis B immunization program on the incidence of acute hepatitis B infection among adolescents in South Korea.
Methods We estimated the counterfactual incidence rate of reported acute hepatitis B among adolescents from 2016 to 2020 compared to the assumption that the national hepatitis B immunization program for children had not been implemented since 1995. The impact of the national hepatitis B immunization program for adolescents was measured by estimating the absolute risk reduction and averted acute hepatitis B infections among adolescents from 2016 to 2020 attributed to the national immunization program.
Results The relative risk reduction of acute hepatitis B among adolescents was estimated to be 83.5% after implementing the national hepatitis B immunization program. The incidence rate of reported acute hepatitis B infections among adolescents decreased from 0.39 to 0.06 per 100,000 person-years, and 43 acute hepatitis B infections, including 17 symptomatic cases, were averted annually from 2016 to 2020 by the national hepatitis B immunization program.
Conclusion The national hepatitis B immunization program for children was effective in preventing acute hepatitis B infection among adolescents in South Korea.
Objectives
Hepatitis B virus (HBV) is a member of the hepadnavirus family. The HBV genome contains four genes designated as S, C, P, and X. The HBV X (HBx) gene encodes for a 16.5-kDa regulatory protein that enhances HBV replication and exerts multifunctional activities. The aim of this study is to describe the rapid and easy purification of HBx using ELP (elastin-like polypeptide) fusion protein. Methods
The ELP–HBx fusion protein was overexpressed in Escherichia coli. Environmental sensitivity was demonstrated via turbidity and dynamic light scattering as a function of temperature. HBx was purified as an ELP fusion protein. ELPs are biopolymers of the pentapeptide repeat Val-Pro-Gly-Xaa-Gly that undergo an inverse temperature phase transition. ELP follows in temperature and salt consistency, precipitation, and solution repetition (inverse transition cycling) with polypeptide, where it purifies the protein in a simple manner. Results
Fusion proteins underwent supramolecular aggregation at 40 ℃ in 1 M NaCl and slowly resolubilized at subphysiologic temperatures. ELP domain proteolysis liberated a peptide of comparable size and immunoreactivity to the commercial HBx. Conclusion
This study suggests that HBx can be purified rapidly and easily using inverse transition cycling, and that this method can be applied in determination of HBx 3D structures and HBx stability study.
Citations
Citations to this article as recorded by
Evaluation of machine learning algorithms to predict the hydrodynamic radii and transition temperatures of chemo-biologically synthesized copolymers Jared S. Cobb, Maria A. Seale, Amol V. Janorkar Computers in Biology and Medicine.2021; 128: 104134. CrossRef
Machine learning to determine optimal conditions for controlling the size of elastin-based particles Jared S. Cobb, Alexandra Engel, Maria A. Seale, Amol V. Janorkar Scientific Reports.2021;[Epub] CrossRef
Influence of miR‐520e‐mediated MAPK signalling pathway on HBV replication and regulation of hepatocellular carcinoma cells via targeting EphA2 Jing‐hui Tian, Wen‐dong Liu, Zhi‐yong Zhang, Li‐hua Tang, Dong Li, Zhao‐ju Tian, Shao‐wei Lin, Ying‐jie Li Journal of Viral Hepatitis.2019; 26(4): 496. CrossRef
Elastin‐like polypeptides: A strategic fusion partner for biologics Agnes Yeboah, Rick I. Cohen, Charles Rabolli, Martin L. Yarmush, Francois Berthiaume Biotechnology and Bioengineering.2016; 113(8): 1617. CrossRef
Elastin-like polypeptides as a promising family of genetically-engineered protein based polymers Tomasz Kowalczyk, Katarzyna Hnatuszko-Konka, Aneta Gerszberg, Andrzej K. Kononowicz World Journal of Microbiology and Biotechnology.2014; 30(8): 2141. CrossRef