AREG and Sepsis: Our scRNA-seq analysis of total PBMC identified a cluster of upregulated genes, shared between sepsis and NEC responses, including AREG, SOCS2 and FKBP5. Universal upregulation of SOCS2 likely reflects tight regulation of cytokine receptor signalling which was revealed from our gene set enrichment analysis to be amongst the top pathways associated with Enterobacter MCS and Stage III NEC and is consistent with another report of SOCS gene upregulation in peripheral blood of very preterm babies with LOS41.