[摘要]：Methods. We compared the NK responses to influenza using umbilical cord blood (UCB) and adult peripheral blood (APB) mononuclear cells and purified NK cells. Results. Influenza A induced dose-dependent apoptosis of NK cells with down-regulation of NKp46 expression, which was more pronounced in UCB. Both UCB and APB NK cells responded to influenza infection by up-regulating CD69 and CD107a expression, a process further enhanced by interleukin (IL) 15. Influenza exposure also down-regulated perforin expression and K562 cytotoxicity in UCB NK cells, which was partially restored by IL-15. The production of interferon (IFN) gamma and tumor necrosis factor (TNF) alpha by NK cells in responding to influenza was further enhanced by IL-15. Conclusions. Our findings show differential NK responses between newborns and adults. IL-15 may be beneficial in combating influenza by enhancing cytotoxic function and IFN-gamma production.
