July 7, 2012— -- Everybody knows that a good immune system helps to fight the flu. Now a new animal study, published in the journal PLoS One, found that a synthetic protein called EP67 can activate the immune system and help fight the flu if it is administered within 24 hours of exposure to the virus.
Researchers from San Diego State University and the University of Nebraska Medical Center tested the protein in mice by first infecting them with the flu virus and then giving them a dose of the protein within 24 hours.
Mice normally lose about 20 percent of their body weight when exposed to the flu, but the mice treated with the protein lost an average of only 6 percent. Some didn't lose any weight at all.
Even more important, researchers said that mice infected with a lethal dose of influenza did not die after receiving the protein.
"EP67 can protect from a lethal dose of influenza even when treatment is delayed for a full day after the time of infection," said Joy Phillips, lead author of the study. "This protection is not limited to a single strain of influenza, as is the case for the vaccine, but should protect against all strains of influenza A or influenza B."
Phillips said the protein has not been tested against highly pathogenic strains like the avian H5N1 influenza, but it's possible it would also protect against such strains.
"EP67 should be effective against a wide variety of pathogens," said Phillips. "Since EP67 works by stimulating local innate immunity, it should prove effective against viral, bacterial and fungal diseases."
While the protein requires much more pre-clinical research before it can be expected to be used in real-world application, Phillips said, in the future, it may be used as an emergency therapeutic for emergency workers, family members and close contacts of patients.
"As an emergency therapeutic, EP67 has the potential to protect against a myriad of possible pathogens without needing to first identify any specific organism," said Phillips. "This has significant implications in the fields of global health and bioterrorism, and to the field of veterinary medicine as well."
She recently discovered that EP67 appears to function in mammals, and even chickens.
"Work focused on bioterrorism often stresses protection against human pathogens, but protecting the world food supply is another extremely important concern," Phillips continued.
Nevertheless, the present study only involved mice, and only one strain of influenza, so the research will have to be extended to other species and involve challenges with multiple flu strains before predictions can be made about applications, said Philip Alcabes, professor in the department of allied health at Adelphi University, who was not involved in the study.
"Still, since surveillance and control of flu viruses circulating among many non-human species is very important for enhancing the protection of human health globally, information like this could point the way to further research that might be very useful," said Alcabes.