How the Novavax technology is different from other coronavirus vaccines

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The newest entry in America’s coronavirus vaccine arsenal uses the oldest technology of the bunch.

FDA approves Novavax covid vaccine

All four vaccines approved by the Food and Drug Administration teach the body’s immune system to recognize and attack the virus that causes covid-19, but each type does it a little differently.

The first two vaccines, from Pfizer-BioNTech and Moderna, debuted with the latest technology. Johnson & Johnson’s vaccine was created using a slightly more conventional method. The latest vaccine to get the green light was made by Novavax using a process commonly used since the 1980s.

What do all four have in common?

Vaccines mimic an infection, giving the immune system something of a practice target so that it learns how to quickly recognize and defend against the real virus.

All four coronavirus vaccines available in the United States prime the immune system with antigens, benign replicas of parts of the virus.


Antigen or

instructions

for antigen

Antigen or

instructions

for antigen

Antigen or

instructions

for antigen

Each type of vaccine delivers a different antigen in a different way, but they all teach the immune system to recognize the proteins that make up the virus’s characteristic spikes. These spikes are the keys that allow the coronavirus to unlock and infect cells.

Once the antigens are inside the body, the reaction is the same.

Specialized cells break down antigens into a form that the immune system can recognize and pass the information on to other cells that organize troops to fight infections.


Antigen-presenting cells (APCs) consume the antigen from the vaccine or made from the instructions in the vaccine. They break down the spiked protein antigen into pieces called peptides and present them to T-helper cells.

T-helper cells use peptides to teach the immune system to recognize the virus and activate immune cells to fight infection if the virus enters the body.

Antigen-presenting cells (APCs) consume the antigen from the vaccine or made from the instructions in the vaccine. They break down the spiked protein antigen into pieces called peptides and present them to T-helper cells.

T-helper cells use peptides to teach the immune system to recognize the virus and activate immune cells to fight infection if the virus enters the body.

Antigen-presenting cells (APCs) consume the antigen from the vaccine or made from the instructions in the vaccine. They break down the spiked protein antigen into pieces called peptides and present them to T-helper cells.

Antigen-presenting cell (APC)

T-helper cells use peptides to teach the immune system to recognize the virus and activate immune cells to fight infection if the virus enters the body.

Then two armies of white blood cells – B cells and killer T cells – prepare to attack.

B cells produce antibodies that attach to the spikes of the coronavirus, blocking the virus from attaching and invading healthy cells.


An antibody

gives

to a virus

The virus is blocked

from attachment

to the cell

An antibody

gives

to a virus

The virus is blocked

from attachment

to the cell

An antibody

gives

to a virus

The virus is blocked

from attachment

to the cell

Meanwhile, killer T cells recognize the antigenic residue on infected cells and kill those cells. This stops the virus from using the cell’s mechanisms to replicate.

The coronavirus vaccines for children under 5 are finally here

Novavax contains lab-grown spikes

The Novavax vaccine is called a subunit vaccine because it uses part of a virus to activate the immune system.

Scientists grow coronavirus spike proteins in the cells of autumn butterflies in giant bioreactors. (Insect cells are especially good at making complex proteins like those that make up spines.)

They mix laundry detergent to create a soap bubble covered in spikes that looks like the coronavirus. They also add an ingredient called an adjuvant that activates the immune system so that it responds more strongly.


HOW PROTEIN SUB UNIT

VACCINES ARE BEING CREATED

Moth cells are used

to generate the spike protein. An ingredient called an adjuvant is added from the soapbark tree.

HOW PROTEIN SUB UNIT

VACCINES WARN

IMMUNE SYSTEM

Inside the body, the adjuvant helps activate immune cells. This allows a smaller dose of spike proteins to be effective.

Copies of spike protein

consumed by APC cells

The adjuvant helps to increase the activation of immune cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW PROTEIN SUB UNIT

VACCINES ARE BEING CREATED

Moth cells are used

to generate the spike protein. An ingredient called an adjuvant is added from the soapbark tree.

HOW PROTEIN SUB UNIT

VACCINES WARN

IMMUNE SYSTEM

Inside the body, the adjuvant helps activate immune cells. This allows a smaller dose of spike proteins to be effective.

Copies of spike protein

consumed by APC cells

The adjuvant helps to increase the activation of immune cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW PROTEIN SUB UNIT VACCINES ARE BEING CREATED

Moth cells are used to generate the spike protein. An ingredient called an adjuvant is added from the soapbark tree.

HOW PROTEIN SUB UNIT VACCINES WARN THE IMMUNE SYSTEM

Inside the body, the adjuvant helps activate immune cells. This allows a smaller dose of spike proteins to be effective.

Copies of spike protein consumed by APC cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

The adjuvant helps to increase the activation of immune cells

Subunit vaccines take longer to produce than newer types. Several cases of heart inflammation have occurred during Novavax trials, although it is unclear whether the vaccine caused the inflammation.

But Novavax has advantages. It remains stable longer under normal refrigeration, does not contain ingredients used in other vaccines that cause allergies, and may appeal to people who prefer an older, more familiar technology. Some influenza, hepatitis B, and herpes zoster vaccines are subunit vaccines.

Pfizer-BioNTech and Moderna supply blueprints in fat bubbles

Novavax injection contains ready-made viral spikes; a Pfizer-BioNTech or Moderna shot contains instructions so the body can make spikes.

These injections are called mRNA vaccines because they contain messenger RNA, a strip of synthetic genetic material which corresponds to the virus. It comes in a small fat balloon.

Once inside a healthy cell, the RNA generates replicas of the spike proteins.


HOW MRNA VACCINES

HAVE BEEN CREATED

A synthesized piece of genetic material from the virus is wrapped in a protective lipid bubble to keep it from disintegrating.

HOW MRNA VACCINES WARNING

IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of spike protein consumed by APC cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW MRNA VACCINES

HAVE BEEN CREATED

A synthesized piece of genetic material from the virus is wrapped in a protective lipid bubble to keep it from disintegrating.

HOW MRNA VACCINES WARNING

IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of spike protein consumed by APC cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW MRNA VACCINES ARE BEING CREATED

A synthesized piece of genetic material from the virus is wrapped in a protective lipid bubble to keep it from disintegrating.

HOW MRNA VACCINES WARN THE IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

Pfizer-BioNTech and Moderna’s injections are the first mRNA vaccines approved for widespread use, but the cutting-edge technology had been in development and testing for years before the pandemic.

RNA coronavirus vaccines can be produced quickly and most people tolerate them well with no more than mild, short-term side effects. But they are not perfect for everyone.

Some people are allergic to an ingredient used to stabilize mRNA vaccines. In rare cases, vaccine recipients – mostly younger men – can develop heart inflammation after vaccination. And some people are hesitant to try new technology.

J&J supplies cold instructions

The vaccine created by Johnson & Johnson also contains instructions for making spikes, but it does so in a different way than mRNA vaccines. As a “viral vector” vaccine, it delivers a gene into the body in a harmless, modified cold virus.

In healthy cells, the gene supplies the codes for the spikes and the cell discards them.


HOW NON-REPLICATION

VIRAL VECTOR VACCINES

HAVE BEEN CREATED

A harmless adenovirus, engineered so that it cannot replicate, is used to carry a gene from the coronavirus into cells.

HOW NON-REPLICATION

VIRAL VECTOR VACCINES

ALERT THE IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of spike protein consumed by APC cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW NON-REPLICATION

VIRAL VECTOR VACCINES

HAVE BEEN CREATED

A harmless adenovirus, engineered so that it cannot replicate, is used to carry a gene from the coronavirus into cells.

HOW NON-REPLICATION

VIRAL VECTOR VACCINES

ALERT THE IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of spike protein consumed by APC cells

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

HOW NON-REPLICATING VIRAL VECTOR VACCINES ARE BEING CREATED

A harmless adenovirus, engineered so that it cannot replicate, is used to carry a gene from the coronavirus into cells.

HOW NON-REPLICATING VIRAL VECTOR

VACCINES WARN THE IMMUNE SYSTEM

Inside the cells, the genetic material acts as instructions for making copies of spiked proteins.

Copies of the spike protein are then used by the immune system to activate immune cells to recognize and stop the virus.

Viral vector technology is not new, but only a few vaccines made from it have been approved for use in humans, including the Ebola vaccine.

Because some people develop a rare but life-threatening blood clotting syndrome within a few weeks of receiving the Johnson & Johnson vaccine, the FDA has restricted its use to those who cannot or choose not to receive any of the other vaccines.

FDA sharply restricts use of Johnson & Johnson injection due to rare blood clots

None of the coronavirus vaccines are made with the oldest technology, which uses weakened or dead versions of the whole virus. Two well-known examples of such vaccines are those for polio and for measles, mumps, and rubella.

sources: Centers for Disease Control and Prevention, National Institute of Allergy and Infectious DiseasesUniversity of Nebraska Medical Center

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