Glycan array could warn of emerging flu strains

Screening of virus glycoproteins on a glycan array has shown that as few as two genetic modifications are sufficient to change a flu virus from one specific for a human cell receptor to one that can potentially infect bird cells (J. Mol. Biol. 2006, 355, 1143). Structural biologist Ian A. Wilson and glycobiologist James C. Paulson of Scripps Research Institute and coworkers carried out the study on human and avian viruses, including the one that caused the 1918 Spanish flu pandemic. By screening an array of 200 human carbohydrates and glycoproteins against different strains of hemagglutinin, a flu virus surface glycoprotein, they showed that a major species barrier between humans and birds could be circumvented by changes at only two positions in the hemagglutinin receptor binding site. The study suggests that glycan arrays might be used to monitor the emergence of flu strains capable of causing human pandemics, such as may occur with the H5N1 avian flu virus of current concern.