NK cell activation during influenza infection is dependent upon secretion of cytokines and chemokines such as "regulated upon activation, normal T cell expressed and secreted" (RANTES) and interferon gamma-induced protein 10 kDa (IP-10) from cells in the respiratory mucosa [15,16] through binding to chemokine receptors CCR5 and CXCR3, respectively. This evidence concerns the gene CXCL10 and influenza.