CCR1 and infection: When the vaccine proteins were targeted toward chemokine receptors 1, 3, and 5 (CCR1/3/5) on APC by means of macrophage inflammatory protein 1-alpha (MIP1α) (CCL3), vaccinated mice were broadly protected against infection with H1N1, H3N2, H5N1, and H7N1 influenza viruses.