Researchers have figured out exactly how neutralizing antibodies block the highly infectious virus. (La Jolla Institute for Immunology via SWNS)
From Talker
By Stephen Beach, via SWNS
Scientists working on a new vaccine have made major progress in the fight to eradicate measles.
US researchers have now discovered exactly how neutralising antibodies work to thwart the highly contagious virus.
The researchers explained that when the measles virus comes into contact with a human cell, the viral machinery unfolds in just the right way, exposing key parts that allow it to fuse with the host cell membrane.
Once the fusion process is complete, the host cell “disappears” and becomes that of the virus.
Using an imaging technique called cryo-electron microscopy, they recently showed in unprecedented detail how potent antibodies neutralize the virus before it can complete the fusion process.
Professor Erica Ollmann Saphire from LJI said: “The incredible thing about this research is that we have captured the nuclear fusion process in action.
“This series of images is like a flip book, allowing us to see snapshots of the fusion protein as it unfolds, and then see the antibody immobilize it before it completes the final step of the fusion process.
“It is likely that other antibodies against other viruses may work in a similar way, but they have never been imaged in this way before.”
The team said their “promising” findings, published in the journal Science, may prove important beyond measles as the virus is just one member of the Paramyxovirus family, which also includes the deadly Nipah virus.
The Nipah virus is less contagious than measles but is known to have a much higher mortality rate.
Kristin Wook
From Talker
“What we learned about the fusion process may have medical relevance to Nipah virus, parainfluenza virus and Hendra virus,” said Dr Dawid Zaila, lead author of the study and a postdoctoral research fellow at LJI.
“These are all viruses with the potential to cause a pandemic.”
Measles is a highly contagious, airborne disease that tends to affect children most severely.
Despite widespread vaccination efforts, the virus remains a major health threat.
There have been 1,603 suspected cases of measles in England and Wales in 2023, up from 735 in 2022 and 360 in 2021, according to the UK Health Security Agency (UKHSA).
Since autumn 2023, large clusters of measles have been occurring in many areas of England.
Measles killed around 136,000 people worldwide in 2022, with most of the victims being unvaccinated or under-vaccinated children under the age of five.
“Measles causes more childhood deaths than any other vaccine-preventable disease and is also one of the most contagious viruses,” Safire said.
“The current vaccines are effective but they cannot be administered to pregnant women or those with weakened immune systems,” Dr Zaira added.
There is no specific treatment for measles, so researchers are searching for antibodies that could be used as an emergency treatment to prevent severe illness.
To better understand how the measles virus fuses with cells, the LJI team turned to an antibody called mAb 77.
(CDC/NIP/Barbara Rice, via Wikimedia Commons)
From Talker
The researchers discovered that mAb 77 targets the measles fusion glycoprotein, which is part of the viral machinery that the measles virus uses to enter human cells through a specialized process called fusion.
The LJI team investigated exactly how antibodies fight the virus.
They found that mAb 77 blocks the virus midway through the fusion process.
Now that they know how mAb 77 works, the team hopes that the antibody could be used as part of a therapeutic “cocktail” to protect people against measles or to treat patients with active measles.
In subsequent experiments, the researchers showed that mAb 77 exerted a “remarkable” protective effect against measles in a cotton rat model of measles virus infection.
Now the team wants to study different antibodies against measles.
Dr Zaira added: “We would like to stop the fusion at various points in the process and explore other therapeutic possibilities.”
