A single dose of an adeno-associated virus (AAV) expressing a broadly neutralizing flu antibody into the nasal passages of mice and ferrets gives them complete protection and substantial reductions in flu replication when exposed to lethal strains of H5N1 and H1N1 flu virus, according to researchers at the University of Pennsylvania’s Perelman School of Medicine.

“The experiments described in our paper provide critical proof-of-concept in animals about a technology platform that can be deployed in the setting of virtually any pandemic or biological attack for which a neutralizing antibody exists or can be easily isolated,” said James M. Wilson, MD, PhD, professor of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania.

“Further development of this approach for pandemic flu has taken on more urgency in light of the spreading infection in China of the lethal bird strain of H7N9 virus in humans.”

Wilson’s team proposed a novel approach to neutralizing activity in various influenza strains. Instead of requiring the elicitation of an immune response, the Penn approach is to clone into a vector a gene that encodes an antibody that is effective against many strains of flu and to engineer cells that line the nasal passages to express this broadly neutralizing antibody, effectively establishing broad-based efficacy against a wide range of flu strains.

“There’s a long history of using antibodies for cancer and autoimmune disease, but only two have been approved for infectious diseases,” said Anna Tretiakova, PhD, Senior Research Scientist, Perelman School of Medicine. “This novel technique has allowed for the development of a prophylactic passive vaccine that is cost effective, easily administered, and quickly manufactured.”