Ng is seen within murine PMNs and importantly, Ng mutants that are more or less susceptible to killing by human PMNs or cationic antimicrobial peptides in vitro have a similar phenotype when tested against murine PMNs and cathelicidins, and are more fit or attenuated compared to the wild-type strain, respectively, during murine infection [58,59]. This evidence concerns the gene NRGN and infection.