Alternative influenza target There is a pressing need for a broadly protective influenza vaccine that can neutralize this constantly varying, deadly virus. Stadlbauer et al. turned their attention away from the current vaccine target—the mutable hemagglutinin—and investigated an alternative, less variable virus-coat glycoprotein: neuraminidase. The authors extracted monoclonal antibodies (mAbs) from a human donor naturally infected with the H3N2 virus subtype. In mice, the mAbs were broadly protective against influenza virus A groups 1 and 2 (human, avian, and swine origin) and some influenza B viruses. These mAbs were also therapeutically effective as late as 72 hours after infection. The wide range of reactivity probably relates to the infection history of the donor, whose plasmablasts generated antibodies with long regions that insert into the active site of the neuraminidase enzyme. Science , this issue p. 499

Broadly protective human antibodies that target the active site of influenza virus neuraminidase