NOD2 and Sepsis: However, no differences between WT and Nod2−/− mice were detected in terms of T cell apoptosis and IFN-γ production, whereas the expression levels of MHC class II, CD80, and CD86 on APCs in Nod2−/− mice were lower than those in WT mice during sepsis (Fig. 2A and Figs. S8, S9).