Home United States USA — Science Here's a look at how the different coronavirus vaccines work

Here's a look at how the different coronavirus vaccines work

360
0
SHARE

Some of the experimental coronavirus vaccines use some very new technology, including software that reprograms cells.
Pfizer’s and Moderna’s vaccines use very similar technology, while AstraZeneca uses a different approach. They are among six vaccines getting some kind of federal government support in the United States and dozens in development around the world. Here’s a look at the technology behind some of the candidates that are the furthest along in development — mostly in Phase 3 clinical trials, the last step before seeking the go-ahead from the US Food and Drug Administration and other regulators around the world. Pfizer and BioNTech Pfizer and its German-based partner BioNTech use a new approach to making vaccines that uses messenger RNA or mRNA. This design was chosen for a pandemic vaccine years ago because it’s one that lends itself to quick turnaround. All that is needed is the genetic sequence of the virus causing the pandemic. Vaccine makers don’t even need the virus itself — just the sequence. In this case, BioNTech researchers used a little piece of genetic material coding for a piece of the spike protein — the structure that adorns the surface of the coronavirus, giving it that studded appearance. Messenger RNA is a single strand of the genetic code that cells can « read » and use to make a protein. In the case of this vaccine, the mRNA instructs cells in the body to make the particular piece of the virus’s spike protein. Then the immune system sees it, recognizes it as foreign and is prepared to attack when actual infection occurs. MRNA is very fragile so it’s encased in lipid nanoparticles — a coating of a buttery substance that can melt at room temperature. That’s why Pfizer’s vaccine must be kept at ultracold temperatures of about minus 100 degrees F (minus 75 degrees C). That means special equipment is needed to transport and store this vaccine. Moderna Moderna’s vaccine is also based on mRNA.

Continue reading...