Could antibody discovery lead to better flu vaccines?

FRIDAY, Dec. 29, 2023 (HealthDay News) — Researchers appear to have discovered a new weapon in the war against a particularly difficult enemy.

They discovered a previously unrecognized class of antibodies that appear to be able to neutralize a variety of influenza strains.

Their findings, recently published in the journal PLOS Biology, could lead to the development of vaccines to protect against influenza more broadly.

Each year, new vaccines are offered based on experts’ best guesses about which strains will dominate. Sometimes they get it right, sometimes not.

“We need annual influenza virus vaccination to keep pace with the continued evolution of the virus,” the authors noted in a journal news release. “Our work suggests that the barriers to achieving broader protective immunity may be surprisingly low.”

A series of studies is paving the way for vaccines to protect against multiple strains of the virus.

Many are focusing on antibodies that protect against both H1 and H3 influenza subtypes. They come in many strains and cause widespread infections.

Led by Holly Simmons of the University of Pittsburgh School of Medicine, researchers on this study focused on one goal.

They focused on a small change found in some H1 strains in the sequence of the building blocks that make up hemagglutinin, a protein that plays a key role early in infection.

The researchers explain that some antibodies that neutralize H3 can also neutralize H1, but not if your hemagglutinin has this change (called a 133a insertion).

Using blood samples from patients, they identified a class of antibodies that neutralize some H3 strains, as well as some H1 strains with or without the 133a insertion.

The vaccine induces the immune system to produce antibodies that bind to hemagglutinin and prevent it from invading human cells. Different antibodies bind to the hemagglutinin part in different ways, and the virus can change over time, creating new strains that can evade old antibodies.

The researchers say this work expands the list of antibodies that could help develop vaccines with broader protection. They add that it also adds to growing evidence supporting changes in the way flu vaccines are produced.

More information

Learn more about vaccines from the U.S. Centers for Disease Control and Prevention.

Source: PLOS Biology, press release, December 21, 2023