Abstract:

This episode of This Week in Virology, recorded live at the 2025 American Society for Virology meeting, features an in-depth interview with 2020 Nobel Laureate Dr. Charlie Rice. Dr. Rice recounts the significant scientific challenges his lab faced in achieving the replication of Hepatitis C virus (HCV) in cell culture, a process that took over 15 years. He details the numerous failures and incremental breakthroughs, including the discovery of a missing genome sequence, the necessity of using a consensus sequence clone, and the crucial role of the chimpanzee animal model. He highlights the pivotal contributions from other labs, such as the development of the subgenomic replicon system, and the eventual success with the JFH1 strain, which finally enabled the complete viral life cycle in culture. The discussion also covers the development of highly effective HCV antivirals, the potential for human challenge trials, the search for better animal models, and his reflections on the evolution of the virology field and concerns over the current state of science funding and public trust.

An Interview with Nobel Laureate Charlie Rice on the Scientific Battle Against Hepatitis C

• 5:29 Early Career and Technical Hurdles: Dr. Rice discusses his early interest in viral genetics in the 1970s, a time when mutagenesis was a random chemical process with little control, highlighting the frustration that drove the development of more precise tools.
• 6:28 The "Simple Experiment First" Philosophy: He reflects on Vincent Racaniello's early work creating an infectious polio DNA clone, noting it "scooped everyone" because it was a simple, direct approach that worked, while others were attempting more complex methods. This taught him the value of trying the simplest experiment first.
• 13:42 A "Bad Career Move": Dr. Rice recalls that starting work on HCV in 1989 seemed like a poor career choice. It was an "impossible virus" with no cell culture system and the chimpanzee as the only, and very limiting, animal model.
• 18:18 The Crucial Collaboration: A phone call from Steve Feinstone at the FDA "changed his life." The collaboration gave his lab access to well-characterized HCV samples and, most importantly, the chimpanzee model, which was essential for testing the infectivity of their engineered viral RNAs.
• 22:18 The Long Road of Failures: Dr. Rice outlines the painstaking "long and winding road" to a working infectious clone:
  • The first attempt with a full-length clone failed in chimps.
  • After discovering a critical, previously unknown 100-base sequence at the 3' end of the genome, they added it, but the clone still failed.
  • Success was finally achieved by creating a "consensus sequence" clone, assembling the most common nucleotide at every position from the virus population in a patient. This synthetic RNA was infectious in chimpanzees.
• 29:37 Breakthroughs from Other Labs: Despite having an infectious RNA, it still wouldn't grow in cell culture. Dr. Rice credits two other critical breakthroughs from other research groups:
  • Ralph Bartenschlager's lab developed a "subgenomic replicon" that could replicate in a small fraction of cells, revealing that "adaptive mutations" were needed for the virus to grow in culture.
  • Takashi Wakita's lab identified the JFH1 strain of HCV, which, unlike others, could replicate efficiently in cells without adaptive mutations. This was the final piece of the puzzle.
• 32:07 A 15-Year Success Story: The combination of these discoveries finally allowed for the production of infectious HCV in cell culture in 2005, a full 15 years after the virus was first identified.
• 43:23 Modern Animal Models: With the chimpanzee model no longer available for research, Dr. Rice's lab has focused on developing other animal models. A significant success has been the use of a Norway rat hepacivirus, which can establish chronic infections in laboratory mice, providing a powerful new tool for studying pathogenesis.
• 49:16 Curing vs. Eliminating HCV: While highly effective antiviral drugs can cure over 95% of infections, eliminating the disease globally is difficult due to the challenge of identifying and treating every infected person. This maintains the need for a preventive vaccine.
• 51:23 The Potential for Human Challenge Trials: The existence of a near-perfect cure makes human challenge trials for HCV more ethically feasible. These small-scale trials, where vaccinated volunteers are intentionally exposed to the virus, could dramatically accelerate the testing and development of new vaccine candidates.
• 57:52 Concerns for the Future of Science: Dr. Rice expresses grave concern over the current political climate and the "destruction of science and public health in the US." He argues for the critical need to convince the public of the value of curiosity-driven basic research, which is the foundation for all future medical breakthroughs.