Consistent with the increased production of IL-4 and IL-13 found in the sepsis-surviving Rag1−/− mice (Fig. 2e), adaptive immunity was not required for the polarization of peritoneal macrophages toward M2 phenotype, since sepsis-surviving Rag1−/− mice showed a similar frequency of peritoneal macrophage expressing CD206 as the WT mice (Fig. 5a). This evidence concerns the gene IL4 and Sepsis.