Vaccine may give lifelong protection from flu

The annual scramble to get a flu vaccination may one day be a thing of the past. In a first for an infectious disease, a flu vaccine has been made out of messenger RNA, the genetic material that controls protein production. What's more, the new vaccine primes immune cells to kill the flu virus over an extended period and can potentially protect against all strains of the virus.

We're protected from flu when our immune system learns to recognize the HA and NA proteins that coat the virus. But flu evolves and those proteins change, so we have no immunity to subsequent strains. For this reason, a new vaccine must be made each year. This takes six months, so manufacturers have to guess which strains will be around the following winter.

Lothar Stitz, of the Friedrich-Loeffler Institute in Riems Island, Germany, has got round these hurdles. He focused on the viral mRNA that controls the production of HA and NA. When our immune cells encounter this mRNA, they translate it into proteins recognized as foreign, generating an immune response.

The mRNA can be mass-produced as a vaccine within a few weeks. In trials, Stitz's team found mRNA vaccines for common flu strains rapidly induced protective levels of antibodies. Better still, the mRNA, unlike HA and NA, induced a response in immune cells such as killer T-cells. They recognize and keep attacking flu viruses even after they have evolved to evade antibodies.

Stitz has also tested an mRNA vaccine to a flu protein which does not vary between strains. The mRNA protected animals against a seasonal human flu strain and H5N1 bird flu, suggesting that a well-chosen mRNA vaccine could give long-term protection against all flu strains.

Combat high blood pressure

People who take in at least 2 percent of their calories from yogurt have lower blood pressure and are about 30 percent less likely to develop hypertension than people who don't eat yogurt, scientists reported at the American Heart Association's High Blood Pressure Research meeting in Washington, D.C.

The yogurt finding is from a study in which researchers followed nearly 2,200 adults for 15 years and assessed their diets periodically with a questionnaire.

Eating at least one 6-ounce serving of yogurt every three days would provide the 2 percent "dose" cited in the study. Yogurt by itself does not lower blood pressure or prevent hypertension. But a diet that includes nutrient-rich foods such as low-fat yogurt instead of less healthy foods does combat high blood pressure.

The Dietary Approaches to Stop Hypertension plan calls for two to three servings of low-fat dairy per day.

Hearing aid to run on ear power

For the first time, an electrical device has been powered by the ear alone. The technology uses a natural electrochemical gradient in inner ear cells, which in the future could power devices such as a hearing aid or brain implant.

Nerve cells use the movement of positively charged sodium and potassium ions across a membrane to create a chemical gradient that drives neural signals. Hair cells in the cochlea use this gradient to convert the mechanical force of the vibrating eardrum into electrical signals that the brain can understand.

A major challenge in tapping this electrical potential is that the voltage created is tiny - a fraction of that generated by an AA battery. Now, Tina Stankovic at Harvard Medical School in Boston and colleagues have developed an electronic chip containing low-resistance electrodes that can harness a small amount of that electrical activity without damaging hearing.

The device was tested in a guinea pig, with the electrodes attached to both sides of the rodent's cochlear hair cell membranes. Attached to the chip was a radio transmitter. After kick-starting the chip with radio waves, it sustained the low-power transmitter for 5 hours.