Current influenza vaccines provide limited protection against various strains of influenza virus. This is because most antibodies produced following vaccination are targeted against a specific portion of the viral hemagglutinin (HA) protein, which varies greatly in different strains of the virus. This immunity becomes ineffective when the virus originally targeted by the vaccine undergoes natural mutation. Thus, influenza vaccines with broad coverage against most, if not all, strains are needed.
In pursuit of this goal, investigators supported by NIAID discovered a highly conserved region of HA present on group 2 influenza A viruses. Group 2 viruses include the currently circulating human H3 and avian H7 viruses, which sporadically cross from birds into humans and have the potential to trigger future pandemics.
Subsequently, the researchers isolated and studied an antibody, CR8020, that targeted and neutralized the highly conserved HA region on H3N2, H7, and H10 flu strains. The antibody specifically interfered with the ability of HA to bind to cell membranes, preventing viruses from entering and infecting cells. When used therapeutically, CR8020 improved the survival rate of H3N2-infected mice.
This discovery may enable development of a universal influenza vaccine and of new, broad-spectrum antibody-based influenza treatments.
Ekiert DC, Friesen RH, Bhabha G, Kwaks T, Jongeneelen M, Yu W, Ophorst C, Cox F, Korse HJ, Brandenburg B, Vogels R, Brakenhoff JP, Kompier R, Koldijk MH, Cornelissen LA, Poon LL, Peiris M, Koudstaal W, Wilson IA, Goudsmit J. A highly conserved neutralizing epitope on group 2 influenza A viruses. Science. 2011 Aug 12;333(6044):843-50.
Last Updated January 08, 2013