Flu Vaccine Made in Yeast Could Last a Lifetime, Scientists Say

Scientists are working on a new kind of flu vaccine that could be made in baker's yeast — the same yeast used to bake bread. Unlike today's flu shots, this new vaccine might protect people for many years, or even a lifetime. Researchers shared their findings at the American Chemical Society meeting in Chicago. The discovery is one of three exciting health stories making headlines this week.

Right now, most flu vaccines are made by growing the flu virus inside chicken eggs. This process has been used for about 80 years. It takes a long time and must be repeated every year because the flu virus keeps changing. Scientists want a faster, cheaper, and longer-lasting option.

The new vaccine uses baker's yeast, known by the scientific name Saccharomyces cerevisiae, to make tiny particles that look like the flu virus but cannot cause infection. These particles show a protein called M2 on their surface. M2 is a part of the flu virus that barely changes from year to year. In fact, the M2 protein has stayed almost the same since the great flu pandemic of 1918.

Most current vaccines target a different protein called hemagglutinin, or HA. The problem is that HA mutates, or changes, very quickly. That is why scientists have to make a new flu shot every single year. By targeting M2 instead, researchers hope the vaccine will work against many strains of flu at once and last much longer.

When mice were given the yeast-made vaccine, they were protected from three different flu strains. Senior researcher Fei Wen from the University of Michigan said she expects the M2 vaccine to provide "broader and longer protection than the current HA-focused vaccines." The team has already shared the technology with a company that is working to turn it into an oral vaccine — one you swallow instead of getting a shot.

In a second health story, scientists found that weak electrical signals sent deep into the brain may help people speak better after a brain injury. A traumatic brain injury, or TBI, can damage the parts of the brain that control speech and swallowing. This can make everyday life very hard for survivors. Researchers at the University of Pittsburgh tested a way to help those patients.

The scientists used low-frequency electrical currents to stimulate a part of the brain called the motor thalamus. In earlier tests, high-frequency currents made speech worse, so the team lowered the frequency by almost three times. They first tried this on patients who were already getting a device implanted to treat a movement disorder called essential tremor. Those patients showed better control of face and throat muscles without any worsening of speech.

The team then tested low-frequency stimulation on a person with serious speech problems caused by a traumatic brain injury. Across three testing sessions, that person's ability to say understandable words improved by 8%, 20%, and 16% when the stimulation was turned on. Scientists consider a 7% improvement to be a small but meaningful gain, and 15% or more to be a large one. The researchers say more studies are needed, but the results are very promising.

In a third story, Chinese scientists studied how the heart grows new blood vessels after a heart attack. When a main artery in the heart gets blocked, the body sometimes builds natural detours called collateral vessels. For a long time, doctors thought these detours grew from existing arteries that got wider. New research in mice shows the real story may be different.

The study found that these new vessels mostly grow from capillaries — the tiniest blood vessels in the body. Researchers used special tools to track where the new vessel cells came from, and most of them started in capillaries, not arteries. The scientists also found that delivering a protein called VEGF-A using mRNA helped the heart grow more of these helpful vessels. This discovery could lead to new treatments that help the heart heal itself after a heart attack.