IL10 and Sepsis: The authors finally proved that NK cell-derived IL-10 is critical for host survival during sepsis using a model of NCR1-CreERT2+/2 Rosa26-tdTomato IL-10flox/flox mice along with Rosa26-tdTomato IL-10flox/flox littermates that were treated with tamoxifen to knock out IL-10 expression in NK cells expressing the CreERT2 (Figure 6a).