TNF and necrotizing enterocolitis: PMN-MDSCs exposed to spermidine exhibited enhanced therapeutic efficacy in mitigating the severity of NEC, as evidenced by increased survival rates, decreased intestinal inflammation, reduced expression of proinflammatory genes (Il1b and Tnfa), upregulated expression of an antiinflammatory gene (Il10), and decreased bacterial abundance in the intestinal wall (Figure 7, B–E).