When we look back at our Integrated Human Practices (iHP), it doesn’t feel like something we carefully planned out on day one. It grew naturally from the questions we faced and the opportunities we had to talk with experts, doctors, patients, and the wider community. As we moved forward, new questions kept appearing, and whenever we had the chance to meet someone, we took it. Each conversation gave us something important — sometimes it confirmed our ideas, other times it pushed us to reconsider them. Step by step, our project took shape through these exchanges. What follows is a record of the key interactions, what we asked, what we learned, and how they changed our path.
At SMBU, about half of our team are international students in China, and comparing different cultural habits is simply part of our everyday life. One thing we noticed early on was how Chinese people often share food from the same plates using chopsticks. It felt unusual to some of us and turned into casual conversations about whether everyday customs like this could affect the spread of infectious diseases. Out of these student discussions, the first idea for our project began to take shape.
Later during our team meetings we discovered two main reasons that made us focus on hepatitis B:
First, it is highly prevalent in China, with around 86 million people living with chronic HBV infection, which accounts for one-third of the world’s cases according to WHO.
Second, the hepatitis B vaccination coverage rate of adults in China is only 26.27%. In comparison, global coverage with three doses of the hepatitis B vaccine is estimated at 84%.
These numbers highlight just how low adult coverage in China is, despite the country’s high disease burden. These facts convinced us that hepatitis B deserved urgent attention, and that our project should be directed toward searching for new solutions.
We met with Professor Zhou Jianwei (周建伟), Director of Infectious Diseases Department at Liling CDC and senior physician, to learn from his clinical experience.
Our question: We wanted to understand the limitations of current antiviral therapies and identify the most urgent unmet needs in HBV treatment.
What we learned: "... But one major issue remains: many patients still struggle to stick with the treatment long-term."
— Zhou Jianwei, Director of Infectious Diseases Department
Experts explained that current oral antivirals (TDF, TAF) must be taken daily, often for life, and that adherence is a serious issue.
"Current treatments mainly target the virus in the bloodstream, not in the liver itself."
— Zhou Jianwei, Director of Infectious Diseases Department
Moreover, they stressed that these drugs mainly suppress HBV DNA in blood, while cccDNA persists
in the liver, making complete elimination impossible.
How it shaped our project: This meeting directly led us to focus on cccDNA as our main target. It validated our approach of developing a CRISPR-based epigenetic therapy and confirmed that our idea responds to a real and pressing medical need.
We met with Wang Chunmei (汪春梅), Head of the Immunization Planning Division and associate chief physician, to learn about vaccination practices and policies.
Our question: We wanted to understand how prevention of HBV is currently
handled in China and what role vaccines play in national strategy.
What we learned: The hepatitis B vaccine has played a critical role. In China,
it was first introduced in 1992 and officially included in the national immunization program in
2002. Before that, around 450 million people in China had already been infected with hepatitis
B. Thanks to the vaccine, the infection rate dropped dramatically, from 9.67% in 1992 to just
0.3% by 2000. The vaccine is primarily used to prevent infection, so it is not considered
necessary for those who are already infected, although receiving it unknowingly while infected
causes no harm.
How it shaped our project: We realized that while prevention through vaccination is highly successful, it offers no solution for the millions already chronically infected. This clarified our positioning: our project does not replace vaccination but complements it by addressing the therapeutic gap.
In addition, this meeting helped us reflect on the human side of hepatitis B — beyond prevention and molecular therapy. As we learned more about vaccination programs and the public’s understanding of HBV, we began to see how stigma and misinformation remain major barriers to care. This realization led us to launch a separate initiative focused on listening to patient experiences and sharing their voices. Through these conversations, we gained invaluable insight into how social perception shapes treatment and awareness. Learn more in Stories Behind HBV, where we document these personal narratives and explore how they inspired us.
![Vasilieva N. S., Head of the Hepatology Center (2025) [Russian]](https://static.igem.wiki/teams/5861/4323/2wbk7fnzqm5mg9553xfmzbol67d6vzdv.avif)
We visited SM-Clinic and spoke with Vasilieva Natalia Sergeevna, Head of the Hepatology Center.
Our question: We asked what types of therapy are considered the current
standard for treating chronic hepatitis B, whether there are prospects for complete elimination
of the virus, and how promising gene therapy might be.
What we learned: Dr. Vasilieva explained that the current standard treatments are nucleos(t)ide analogues, with entecavir and tenofovir (in its two modifications) regarded as the gold standard. These drugs only suppress viral DNA replication and unfortunately do not act on HBsAg.
"All clinical trials of drugs aimed at eliminating HBsAg replication within the nucleus have so far been unsuccessful. However, hepatitis B does have one major advantage compared to, for example, hepatitis C: we have vaccination."
— Vasilieva Natalia Sergeevna, Head of the Hepatology Center
At present there are no therapies capable of achieving full elimination of HBV; clinical trials
aimed at clearing HBsAg have not succeeded. She also noted that even liver transplantation does
not guarantee cure, since HBV persists as cccDNA and can continue replicating in the new liver.
How it shaped our project: These insights confirmed for us that existing drugs
cannot achieve elimination and that even radical interventions are insufficient. It reinforced
our conviction that HBV must be addressed at the molecular level by directly targeting cccDNA to
achieve durable repression.
After these first meetings we held an internal team discussion to bring everything together. We outlined three main takeaways:
(1) patient adherence to current daily treatments is a critical weakness,
(2) vaccination protects the uninfected but does nothing for those already living with chronic HBV,
and (3) no existing therapy can eliminate the virus because of cccDNA persistence.
From these points we drafted our first proposal: to design a CRISPR-dCas based system that could repress HBV cccDNA and block its transcription, aiming for a long-term solution where existing approaches fall short.
Our question: We wanted to test our early design by presenting it to the synthetic biology community and receiving feedback on feasibility.
What we learned: During the poster session, we were asked two main questions: (1) how to deliver our dual dCas system into hepatocytes, and (2) whether epigenetic silencing would be durable enough.
How it shaped our project: These questions highlighted critical technical gaps. As a result, we decided to explore delivery systems, and strengthen mechanisms for stable repression.
We met with Peng Bo (彭博), Assistant Director of the Institute of Pathogen Biology at Shenzhen CDC.
Our question: We wanted to understand what ethical, regulatory, and technical issues experts see as most critical for gene-editing based therapies in China.
What we learned: Experts emphasized that after the 2018 He Jiankui case, China enforces very strict regulation on gene-editing research. The key issue they highlighted was the danger of unintended off-target effects. Any therapeutic design must therefore show clear evaluation and control of such risks.
How it shaped our project: This meeting made us realize that demonstrating precision is not optional but essential. It reinforced the importance of developing ways to minimize off-target effects, and it set the stage for us to think about new design elements to improve the specificity of repression.
Additionally, insights from our discussions with the CDC went beyond technical and ethical considerations. They also deepened our understanding of how HBV is transmitted and what challenges remain in its prevention today, leading us to expand our public education efforts. These findings directly inspired our awareness campaign on infection routes — particularly the growing role of sexual transmission — which later evolved into a joint outreach initiative with Shenzhen Hospital and the University Health Center. Learn more in Public Engagement.
We met with Associate Professor Qin Peiwu (秦培武) from Tsinghua University, whose research focuses on chromosome structure and its relation to gene transcription and cellular function, the role of long noncoding RNA phase separation in stress response and heterochromatin modification, fluorescence imaging methods, and microfluidic viral RNA detection.
Our question: After CCiC, we wanted to seek deeper technical advice on how to address the challenges raised during the conference.
What we learned: The experts focused on one key issue: the durability of our system. They asked how stable epigenetic repression would be and whether repeated interventions would be needed. As a practical suggestion, they advised performing an in vitro assay using DNA polymerase to check the persistence of Cas protein binding to target DNA and the stability of cccDNA repression.
How it shaped our project: This feedback turned into a concrete experimental plan. Together with our PI we decided to set up a simple yet informative assay: testing in vitro how long Cas proteins can remain bound to their target sites using a DNA polymerase system. This experiment will provide direct evidence about the stability of our design and guide further strategies for achieving durable repression.
We met with Ping Zhi (平质), lecturer at CUHK specializing in DNA data storage, bioinformatics, DNA synthesis technologies, and synthetic biology.
Our question: We wanted to discuss how to further reduce off-target effects and optimize the molecular design of our system.
What we learned: Experts recommended focusing on already well-characterized target regions within HBV cccDNA instead of designing entirely new ones, as this would reduce the likelihood of off-target interactions. To optimize RNA–RNA interactions, they suggested using computational tools such as RNAfold and NUPACK for predicting and validating secondary structures before experimental testing. Another key point raised was that simultaneously introducing three plasmids into a cell can significantly reduce transfection efficiency and damage the cells. They advised testing sequential or single-plasmid transfer approaches to improve success rates.
How it shaped our project: Based on this advice, we incorporated computational validation into our workflow and began using RNAfold and NUPACK to refine sgRNA pairing. We also reconsidered our plasmid delivery strategy, planning to evaluate transfection efficiency when introducing plasmids separately rather than simultaneously.
After these exchanges we once again came together as a team to reflect on what we had learned. We saw three clear points:
(1) delivery remains the central technical challenge for any gene-based therapy,
(2) specificity must be improved to convincingly address ethical and safety concerns,
and (3) durability of repression is essential for long-term effectiveness.
To respond to these points, we took three concrete actions: we studied the literature on delivery strategies to better understand possible solutions, we decided to explore a dual dCas system to increase specificity and reduce off-target risks, and we planned the in vitro DNA polymerase assay to test how long Cas proteins can remain bound to their targets and how stable repression can be maintained.