Conversely, we found a significant decrease in the proportion of CD28-CD27- defined CD8+ TEMRA in intestinal mucosa tissue of patients with NEC compared to that in controls (Figure 4E), suggesting that the CD8+ TEMRA subset with pro-inflammatory cytokines and cytotoxins tends to migrate to the periphery during NEC development, thereby exacerbating systemic inflammation (Figure 4F). Here, CD28 is linked to necrotizing enterocolitis.