This episode of "This Week in Virology" is a live recording from the Harvard Virology Retreat in Waterville Valley, New Hampshire. Host Vincent Racaniello speaks with three Harvard-affiliated scientists: Aaron Schmidt, Ben Gewurz, and graduate student Tatum Sass. The discussion begins with the purpose of a scientific retreat and a tribute to the late David Baltimore before delving into the personal and scientific journeys of each guest. Aaron Schmidt details his lab's work on developing next-generation influenza vaccines by using protein engineering to target conserved epitopes on the hemagglutinin head, aiming to elicit potent, broadly neutralizing antibodies. Tatum Sass explains her doctoral research on optimizing CAR-T cell therapy to target and eliminate HIV-infected cells by enhancing the affinity of the targeting domain. Ben Gewurz provides an overview of his research on the ubiquitous Epstein-Barr virus (EBV), covering its links to infectious mononucleosis, various cancers, and autoimmune diseases like multiple sclerosis, as well as the potential for an EBV vaccine. The episode concludes with a candid discussion on the current challenges facing scientific research in the U.S., including funding cuts and political attacks, and the importance of community and perseverance in maintaining morale.
Harvard Virology's Research and Future Outlook
0:52 The podcast is recorded live from the annual Harvard Virology Retreat, an event designed for scientific exchange, community building, and welcoming new graduate students.
2:52 Host Vincent Racaniello and the guests pay tribute to the renowned virologist David Baltimore, who recently passed away and was a formative mentor and scientist.
12:48 The guests share their personal journeys into science. Aaron Schmidt transitioned from a strong interest in theater, Tatum Sass was inspired by a personal illness with adenovirus, and Ben Gewurz comes from a family of scientists.
22:37Aaron Schmidt's Influenza Research: His lab focuses on designing next-generation influenza vaccines. Their strategy involves using protein engineering to focus the immune system on conserved, broadly neutralizing epitopes on the virus's hemagglutinin (HA) protein.
29:54Key Takeaway (Influenza): Schmidt argues that targeting the conserved receptor-binding site on the HA head is more effective for eliciting potent neutralizing antibodies than focusing solely on the HA stem, which is the target of many universal vaccine efforts.
36:36 The discussion explores how "recalled humoral immunity" (also known as immune imprinting or original antigenic sin) from prior exposures influences how the immune system responds to new, drifted flu strains and how this impacts viral evolution.
42:11Tatum Sass's HIV Research: As a graduate student, her work focuses on developing and improving Chimeric Antigen Receptor (CAR)-T cells, a type of immunotherapy, to specifically kill cells infected with HIV.
43:12Key Takeaway (HIV): Sass is working to optimize the CAR-T cell's targeting domain, which uses the CD4 protein to recognize the HIV envelope, to increase its binding affinity and improve its ability to kill infected cells.
49:04Ben Gewurz's EBV Research: His lab studies Epstein-Barr virus (EBV), a herpesvirus that infects over 95% of the adult population and establishes lifelong latent infection in B cells.
50:41Key Takeaway (EBV): EBV is linked to a range of diseases, including infectious mononucleosis, several types of cancer (like Burkitt lymphoma and nasopharyngeal carcinoma), and autoimmune conditions, most notably multiple sclerosis (MS).
52:52 The virus can reactivate from its latent state, particularly when B cells are stimulated by other infections (e.g., COVID-19 or influenza), though this reactivation is typically asymptomatic.
1:01:55 An effective EBV vaccine is being pursued, with the potential to prevent not just mono but also the downstream development of EBV-associated cancers and MS.
1:03:15 The panel discusses the challenging climate for science in the US due to funding cuts and political rhetoric, emphasizing that events like the retreat are crucial for maintaining morale and supporting the next generation of scientists.
Summary of Provided References
"Conserved sites on the influenza H1 and H3 hemagglutinin..." (Science Advances): This paper from Aaron Schmidt's lab isolates and characterizes human monoclonal antibodies that can neutralize a broad range of influenza H1 and H3 subtypes. The research maps the specific, conserved sites (epitopes) on the HA protein that these antibodies target, identifies potential viral escape mutations, and demonstrates that antibody potency can be improved through directed evolution.
"Antigenic drift expands influenza viral escape pathways..." (Immunity): Also from Schmidt's lab, this study investigates how immune imprinting (a memory response based on initial exposure) impacts influenza's ability to evade the immune system. It finds that while antibody responses can mature to recognize drifted strains, this process can paradoxically open up new evolutionary escape routes for the virus, explaining its persistent circulation.
"Epstein-Barr virus latent membrane protein 1 subverts..." (PLoS Pathogens): This research from Ben Gewurz's lab explores how the EBV oncoprotein LMP1 reprograms the metabolism of B cells to drive cancer. It highlights that LMP1 makes the cancer cells highly dependent on a specific metabolic pathway (purine biosynthesis), suggesting that inhibiting this pathway could be a novel therapeutic strategy for EBV-driven lymphomas.
Glossary of Scientific Terms
Broadly Neutralizing Antibodies: Powerful antibodies that can recognize and inactivate many different strains or subtypes of a virus (e.g., many different influenza viruses).
CAR-T (Chimeric Antigen Receptor T-cell) Therapy: An immunotherapy where a patient's own T-cells (a type of immune cell) are genetically engineered in a lab to produce special receptors (CARs) on their surface. These receptors allow the T-cells to better identify and kill specific targets, such as cancer cells or virus-infected cells.
Epitope: The specific part of a molecule on a pathogen (like a protein on a virus) that is recognized and bound by an antibody.
Epstein-Barr Virus (EBV): A very common herpesvirus that causes infectious mononucleosis ("mono") and is associated with several types of cancer and autoimmune diseases. It establishes a lifelong latent infection.
Hemagglutinin (HA): A protein on the surface of the influenza virus that it uses to bind to and enter host cells. It is the primary target for neutralizing antibodies.
Immune Imprinting (Original Antigenic Sin): A phenomenon where the immune system's response to a new, but related, pathogen is biased by the memory of the first time it encountered that type of pathogen. This can be helpful but can also limit the effectiveness of the response to the new variant.
Latency (Viral): A phase in a virus's life cycle where it exists inside a host cell but does not actively replicate or cause disease. The virus can remain in this dormant state for long periods before reactivating.
Monoclonal Antibodies (mAbs): Laboratory-produced antibodies that are all identical clones of a single parent antibody. They are designed to recognize and bind to a single, specific epitope.
Oncometabolism: The study of how cancer cells alter their metabolism (the chemical processes that generate energy and building blocks) to support their rapid growth and proliferation.