Could this technology end all viruses?

Summary

The script explores the development of a universal vaccine, focusing on a flu vaccine that could protect against all strains, including future mutations. It explains how hemagglutinin proteins on the virus mutate, causing the need for annual flu shots due to antigenic drift and shift. Scientists are targeting conserved regions of hemagglutinin for a universal vaccine. Promising research involves using ferritin nanoparticles to present viral proteins to the immune system, showing potential in protecting against different flu subtypes. The script also touches on the broader potential of training the immune system with T cells for even more extensive protection.

Takeaways

• 🌐 The pursuit of a universal vaccine that protects against all diseases is a monumental public health ambition.
• 💉 Current research is focusing on a universal flu vaccine that could protect against all strains of the flu, including future mutated ones.
• 🔬 Hemagglutinin proteins on the surface of the flu virus are crucial for infection and are a primary target for the immune system's antibodies.
• 🧬 Antigenic drift, caused by small mutations in the virus' RNA, leads to changes in hemagglutinin that can reduce the effectiveness of existing antibodies.
• 🐖 Antigenic shift occurs when different flu viruses recombine in a host, potentially creating a new strain to which humans have no immunity.
• 🛡 A universal flu vaccine aims to target conserved regions of hemagglutinin that are less prone to mutation and critical for infecting human cells.
• 🔬 Scientists are exploring the use of ferritin nanoparticles to present viral proteins in a way that is highly recognizable to the immune system.
• 🐁 In a study, mice vaccinated with a ferritin nanoparticle presenting a flu virus' neck region were protected against a lethal dose of a different subtype.
• 🔬 The immune system's T cells, which can kill virus-infected cells, are being considered for broader vaccine development to provide additional protection.
• 🚀 While a universal vaccine for all infectious diseases remains in the realm of science fiction, advancements in medicine and technology could make it a reality in the future.

Q & A

What is the significance of the round structure mentioned in the script?

The round structure refers to a hemagglutinin protein found on the surface of flu viruses, which plays a crucial role in initiating infection by attaching to human cells. It is also a primary target for the immune system's antibodies.

How does hemagglutinin mutate, and what is the consequence of these mutations?

Hemagglutinin mutates through changes in the virus' RNA, often subtle mutations that result in single letter changes. These mutations can lead to antigenic drift, where the protein's structure changes enough that existing antibodies become less effective at recognizing it, necessitating annual flu vaccinations.

What is antigenic shift, and how does it differ from antigenic drift?

Antigenic shift refers to the recombination of viral genomes from different strains infecting the same cell, potentially creating a new virus with a hemagglutinin that has never infected humans before. This can lead to pandemics, unlike antigenic drift, which involves more subtle mutations.

Why is it challenging to develop a universal flu vaccine?

Developing a universal flu vaccine is challenging because flu viruses are constantly mutating, and there may not be a single conserved region common across all influenza strains and subtypes. Additionally, conserved regions that could be vaccine targets are often located in areas, like the neck of hemagglutinin, that the immune system does not easily recognize.

What are 'conserved regions' in the context of flu viruses?

Conserved regions are parts of the hemagglutinin protein that have remained relatively unchanged over time and are likely critical for infecting human cells. These regions are considered promising targets for developing a universal vaccine.

How does the ferritin nanoparticle technology contribute to vaccine development?

Ferritin nanoparticles can be engineered to present multiple copies of a viral protein, such as the conserved neck region of hemagglutinin. When used as a vaccine, it can stimulate an immune response against these conserved regions, potentially providing broader protection against different flu strains.

What role do T cells play in the immune response, and how could they be utilized in vaccine development?

T cells are part of the immune system that can kill cells infected by viruses. Vaccines that also train this part of the immune system, in addition to the antibody response, could provide broader protection against various strains of a virus.

What is the potential of using conserved regions across different virus species for vaccine development?

The potential of using conserved regions across different virus species lies in the possibility of developing vaccines that could protect against a broader range of related viruses, such as SARS-CoV-2, MERS, and some common cold coronaviruses.

Why is a universal flu vaccine considered a monumental achievement in public health?

A universal flu vaccine would provide protection against all current and future strains of the flu, reducing the need for annual vaccinations and potentially preventing pandemics, thus having a significant positive impact on public health.

What are the current limitations in developing a vaccine that protects against all infectious diseases?

The current limitations include a lack of understanding of how the immune system would react to being trained against hundreds of different diseases simultaneously, which could potentially overwhelm the immune system.

How does the script suggest the future of medicine might evolve in terms of vaccine development?

The script suggests that while a universal vaccine against all infectious diseases is currently in the realm of science fiction, the rapid advancements in medicine could lead to groundbreaking technologies that might make such vaccines possible in the future.

Outlines

00:00

💉 The Quest for a Universal Flu Vaccine

This paragraph delves into the development of a universal flu vaccine that could protect against all strains of the flu, including those that haven't emerged yet. It explains the structure of the flu virus, highlighting the hemagglutinin protein that plays a crucial role in infection and is a primary target for the immune system. The concept of antigenic drift and shift is introduced, explaining how these mutations necessitate annual flu vaccines. The paragraph also explores the challenges in creating a vaccine against a virus that is constantly changing, focusing on the 'conserved regions' of hemagglutinin that are less prone to mutation. A novel approach using ferritin nanoparticles to present these conserved regions to the immune system is discussed, demonstrating promising results in mice. The potential for this technology to be applied to other viruses, such as coronaviruses, is also mentioned.

05:01

🔮 The Future of Universal Vaccines in Medicine

The second paragraph contemplates the broader ambition of developing a universal vaccine that could protect against all infectious diseases. It acknowledges the current limitations in training the immune system to respond to hundreds of different diseases simultaneously. However, it also expresses optimism about the future of medicine, drawing a comparison between the present state of medical knowledge and that of two centuries ago. The paragraph concludes with a speculative but hopeful outlook on the possibility of future technologies making universal vaccines a reality, suggesting that what seems like science fiction today could become achievable with advancements in medical science.

Keywords

💡Hemagglutinin

Hemagglutinin is a protein found on the surface of influenza viruses, including the flu virus. It plays a crucial role in the virus's ability to infect host cells by binding to receptors on the cell surface and initiating the fusion process. In the video, hemagglutinin is likened to the head of Napoleon Bonaparte, emphasizing that the immune system primarily recognizes and targets this part of the virus. The constant mutation of hemagglutinin, known as antigenic drift, is a key challenge in developing a universal flu vaccine, as it can change to the point where existing antibodies are less effective at recognizing it.

💡Antigenic Drift

Antigenic drift refers to the gradual changes in the antigenic properties of a virus due to mutations. This term is central to the video's discussion on the flu virus's ability to evade the immune system. The video explains that most mutations in hemagglutinin are subtle, caused by single-letter changes in the virus's RNA, which can accumulate over time, leading to significant changes that reduce the effectiveness of existing antibodies. This is why people need a new flu vaccine annually.

💡Antigenic Shift

Antigenic shift is a more dramatic and sudden change in a virus's antigenic properties, often resulting from the recombination of viral genomes within a host cell infected with two different strains of the virus. This can lead to the emergence of a new virus strain to which the human population has little or no immunity, as illustrated in the video by the example of a pig being infected with both human and bird flu strains. Such shifts can result in epidemics or pandemics, underscoring the need for a universal vaccine that can protect against a wide range of strains.

💡Conserved Regions

Conserved regions are parts of a virus's genetic material or protein structure that remain relatively unchanged over time, often because they are essential for the virus's survival and function. In the context of the video, these regions of the hemagglutinin protein are potential targets for a universal vaccine because they are less likely to mutate and thus could be recognized by the immune system across different flu strains. The challenge is that these regions are often less immunogenic, making it harder to stimulate an immune response.

💡Ferritin Nanoparticle

Ferritin is a protein that naturally occurs in the body and is involved in iron storage and transport. In the video, it is highlighted for its potential use in vaccine design due to its size and shape, which are similar to small viruses. Scientists have engineered a ferritin nanoparticle to display multiple copies of a conserved region of the flu virus, effectively tricking the immune system into recognizing and responding to a part of the virus that is less prone to mutation. This approach has shown promising results in preclinical studies, where vaccinated mice were protected against a lethal dose of a different flu subtype.

💡Universal Vaccine

A universal vaccine is a hypothetical vaccine that would provide broad or lifelong protection against a particular disease or a group of diseases. The video discusses the ambitious goal of creating a universal flu vaccine that could protect against all strains of the flu, including those that have yet to emerge. This concept is central to the video's theme of pushing the boundaries of vaccine science to achieve a significant breakthrough in public health.

💡Immune System

The immune system is the body's defense mechanism against pathogens, such as viruses and bacteria. It includes various cells, proteins, and organs that work together to identify and neutralize threats. In the video, the immune system's role in recognizing and responding to viral proteins like hemagglutinin is discussed. The video also touches on the potential of training different parts of the immune system, such as T cells, to provide broader protection against viruses.

💡RNA

RNA, or ribonucleic acid, is a molecule that plays a crucial role in the synthesis of proteins and is involved in the regulation of the genome. In the context of the video, RNA is mentioned as the genetic material inside flu virus particles. The mutations in the virus's RNA can lead to changes in the hemagglutinin protein, which is a significant factor in the virus's ability to evade the immune system and cause disease.

💡T Cells

T cells, a type of white blood cell, are a critical component of the adaptive immune system. They can recognize and kill cells that have been infected by viruses, among other functions. The video suggests that vaccines that can activate T cells, in addition to stimulating antibody production, could provide a more comprehensive protection against viruses. This approach is part of the ongoing research into developing a universal vaccine.

💡Epidemics and Pandemics

An epidemic refers to the widespread occurrence of an infectious disease in a community at a particular time. A pandemic is an epidemic that spreads across multiple countries or continents. The video discusses how antigenic shifts in the flu virus can lead to new strains that have the potential to cause epidemics or pandemics due to the lack of pre-existing immunity in the population.

💡Science Fiction

The term 'science fiction' is used in the video to describe the idea of a universal vaccine against all infectious diseases as something that is currently beyond our reach. It serves as a contrast to the real and ongoing scientific efforts to develop a universal flu vaccine, highlighting the ambitious and futuristic nature of such a goal. The video ends on a hopeful note, suggesting that while a universal vaccine for all diseases may be in the realm of science fiction now, future advancements could make it a reality.

Highlights

The potential development of a universal vaccine that protects against all strains of the flu, including those that don't exist yet.

The role of hemagglutinin proteins in the flu virus, which attach to human cells and initiate infection.

The immune system's response to hemagglutinin, focusing on its head for recognition and memory.

The concept of making antibodies as 'plaster molds' of parts of the virus to remember and fight future infections.

Hemagglutinin's constant mutation leading to antigenic drift, requiring annual flu shots.

Antigenic shift, a more significant change in the flu virus due to recombination with bird flu, leading to potential pandemics.

The challenge of designing a vaccine against a strain that doesn't exist yet, by looking at conserved regions of hemagglutinin.

The difficulty in getting the immune system to react to conserved regions in the 'neck' of hemagglutinin.

The use of ferritin, a protein that can be engineered to present viral proteins and stimulate an immune response.

A successful experiment where mice were vaccinated with a ferritin nanoparticle and survived a lethal dose of a different flu subtype.

The exploration of conserved regions across different virus species for broader vaccine development.

The emerging understanding of T cells' role in the immune system and their potential in vaccine development.

The theoretical possibility of a fully universal vaccine against all infectious diseases, despite current challenges.

The comparison of medical advancements over the past centuries and the potential for future breakthroughs in universal vaccine technology.

Transcripts

This round structure is only about ten billionths of a meter in diameter,

but it— as well as other technologies in the pipeline—

could be stepping stones to a monumental public health ambition:

a single vaccine that protects you against everything.

We’ll get back to the grand vision later, but first,

let’s start with something that’s being developed now:

a vaccine that would protect you against every strain of the flu—

even ones that don’t exist yet.

Here’s one flu virus particle.

On the inside is the virus’ RNA,

and on the outside are lots and lots of hemagglutinin proteins.

Hemagglutinin attaches to a receptor on a human cell

and fuses the viral and human membranes, starting the infection.

Hemagglutinin is also one of the things your immune system recognizes

and reacts to the most.

To understand how this works,

think of hemagglutinin as a bust of 19th century French Emperor Napoleon Bonaparte.

Croissant!

If you show Napoleon to an immune system and say, “remember him,”

the immune system will mostly focus on his head.

And the same is true for the real hemagglutinin.

One way the immune system remembers things

is by physically interacting with them.

Think of it as making plaster molds of parts of the head:

we call these molds antibodies.

The antibodies float around your bloodstream for a while

and then can diminish,

but blueprints on how to make them are stored in specialized memory cells,

waiting for future Napoleons to invade.

Here’s the thing, though.

Hemagglutinin is constantly mutating.

Most mutations are subtle,

produced by single letter changes in the virus’ RNA: like this or this.

Over time, Napoleon-slash-hemagglutinin’s head can change enough

that our antibodies become less good at recognizing it.

This is called antigenic drift.

Influenza is constantly drifting;

that’s one reason you have to get a new flu shot every year.

But sometimes bigger changes happen.

An animal, usually a pig, can get infected with, say,

a human flu and a bird flu.

And those different viruses might infect the same cell.

If that happens, the two different viral genomes can recombine

in tens or even hundreds of ways.

The human flu virus could pick up a bird flu hemagglutinin

that’s never infected humans before.

This is called antigenic shift,

and if you get infected by this version of influenza,

none of the antibodies against Napoleon's head are going to help you.

Antigenically shifted viruses have the potential

to infect many people very quickly,

causing epidemics and sometimes pandemics.

A truly universal flu vaccine would be able to protect

against current flu strains and future drifted or shifted strains.

But how do we design a vaccine against a strain that doesn’t exist yet?

We look to the past.

There are key parts of hemagglutinin that haven’t changed much over time

and are probably critical to infect human cells;

these “conserved regions” could be promising targets for universal vaccines.

But there's a problem that's hindered classical vaccine production.

Many conserved regions are in the neck,

and it’s tough to get the immune system to react to the neck.

Also, because influenza-like viruses have been around

for hundreds of millions of years,

there may not be a single region that’s common across all species

and subtypes of influenza.

But there’s promising science in development.

Remember this?

This is a protein called ferritin;

Its normal purpose is to store and move iron.

But it’s also the rough size and shape of a small virus.

And if you attach viral proteins to it, like this,

you’d have something that looks, to an immune system, like a virus—

but would be completely harmless and very engineerable.

Recently, scientists engineered a ferritin nanoparticle

to present 8 identical copies of the neck region of an H1 flu virus.

They vaccinated mice with the nanoparticle,

then injected them with a lethal dose of a completely different subtype,

H5N1.

All the vaccinated mice lived; all the unvaccinated ones died.

Going one step beyond that,

there may be conserved regions that we could take advantage of

across different-but-related virus species—

like SARS-CoV-2, MERS,

and a few coronaviruses which cause some common colds.

Over the past few decades,

a different part of the immune system has come into clearer focus.

Instead of antibodies, this part of the immune system

uses a vast array of T cells that kill, for example,

cells that have been infected by a virus.

Vaccines that train this part of the immune system,

in addition to the antibody response, could provide broader protection.

A universal flu vaccine would be a monumental achievement in public health.

A fully universal vaccine against all infectious disease is— for the moment—

squarely in the realm of science fiction,

partially because we have no idea how our immune system would react

if we tried to train it against hundreds of different diseases at the same time.

Probably not well.

But that doesn’t mean it’s impossible.

Look at where medicine is today compared to where it was two centuries ago.

Who knows what it’ll look like in another 50 or 100 years—

maybe some future groundbreaking technology

will bring truly universal vaccines within our grasp.