The best way to prevent influenza is by immunization. Unlike
vaccines for polio and measles, which confer life-long immunity,
the influenza vaccine protects for only one year. Influenza
virus undergoes antigenic variation, necessitating annual
production of a new vaccine. Is it possible to formulate an
influenza vaccine that protects against all virus strains for
life? Two studies of newly isolated monoclonal antibodies
against influenza virus suggest that the answer could be yes.
The authors of one study identified human antibodies against
influenza virus by phage display. In this technique, recombinant
HA protein (the H5 subtype) was used to bind bacteriophage
particles that bear on their surfaces variable chains of human
antibodies. Ten antibodies were identified that neutralized the
infectivity of H5 influenza viruses in cell culture. The
antibodies also protected mice against lethal H5N1 influenza
even when administered after infection. The key result is that
the monoclonal antibodies neutralize infectiv