Inhaled protein my aid in the fight against influenza

A protein that boosts the immune system may be able to aid in the fight against the flu, a new report says, by reducing symptoms and even preventing death despite lethal doses of the flu.

In a study led by Dr. Homayoun Shams from the University of Texas, scientists tested the effect of the protein granulocyte macrophage-colony stimulating factor against a lethal dose of the flu in mice.

Mice treated with GM-CSF survived the lethal dose of the flu virus, while those untreated died within a few days. This nasal aerosol treatment may help to protect against the flu, of which there are three to five million cases worldwide each year, reports the BBC.

"Such unique and unambiguous results demonstrate the great potential of GM-CSF and may be the remedy for a critical public health priority - developing strategies to reduce the morbidity and mortality from influenza,” Shams said, according to the BBC. “Despite the widespread use of vaccines, influenza causes significant morbidity and mortality throughout the world, and those with poor immune systems are particularly more susceptible—such as very young, elderly or immunocompromised individuals.

"Unlike a vaccine, GM-SCF does not rely heavily on the body's ability to mount an immune counter-attack against a specific antigen or virus strain, but enhances the speed of local responses to virus infection and delicately balances the host immune responses."

GM-SCF has already been used to treat patients who have the blood disorder neutropenia. The protein is known to boost the activity of what are called alveolar macrophages, which act as a first line of defense against inhaled molecules and organisms.

Professor John Oxford, a virologist based at Queen Mary, University of London, said that even if the work is not directly transferable to humans, it may be helpful in directing research.

"Transferring it into humans can be quite difficult,” Oxford said, according to the BBC. “We don't know the sort of problems that could occur if you start meddling with the immune system, as we saw with the Northwick Park trial [in which six men became seriously ill after taking a drug which was meant to "retune" the immune system]. So first we'll see how it pans out in mice, then see how it can possibly apply to humans. But it could also help our understanding of the pathology of flu."