Universal Influenza Vaccine against H5N1, H3N2, and H1N1 Shown Effective in Pre-Clinical Trials
Researchers in the Center for Biologics Evaluation and Research and the Centers for Disease Control and Prevention developed a "universal," off-the-shelf vaccine designed to reduce illness and slow the spread of disease caused by new influenza A viruses that emerge suddenly, spread quickly, and for which there is no specific vaccine available. A single dose of the vaccine reduced illness and virus levels in mice later infected with highly virulent (disease-causing) H1N1 and H3N2 (seasonal influenza), and H5N1 (bird flu).
The key to the new vaccine's broad protection is that it is designed to trigger immune responses against proteins called NP and M2--two protein targets in all influenza viruses that change over time much more slowly than the HA and NA proteins targeted by traditional vaccines. The vaccine is designed to express NP and M2 from a replication-defective form of another respiratory virus, and is administered nasally, which enables it to stimulate the immune system in the mucous membranes, where influenza viruses launch their infection.
This type of vaccine, if effective in humans, could be stockpiled and then used to reduce deaths and severe illness in the event of delayed production of traditional vaccine against a newly emergent influenza virus.
"Single-dose Mucosal Immunization with a Candidate Universal influenza Vaccine Provides Rapid Protection from Virulent H5N1, H3N2 and H1N1 Viruses"
PLoS 2010; 5(10) October 4
Graeme E. Price, Mark R. Soboleski, Chia-Yun Lo, Julia A. Misplon, Mary R. Quirion,
Suzanne L. Epstein (Food and Drug Administration, Bethesda, MD)
Katherine V. Houser, Melissa B. Pearce, Claudia Pappas, Terrence M. Tumpey
(Centers for Disease Control and Prevention, Atlanta, GA)