The underlying health-driving mechanisms of Bifidobacterium during early life are not well understood, particularly how this microbiota member may modulate the intestinal barrier via programming of intestinal epithelial cells (IECs). We investigated the impact of Bifidobacterium breve UCC2003 on the transcriptome of neonatal murine IECs. Small IECs from two-week-old neonatal mice administered B. breve UCC2003 or PBS (control) were subjected to global RNA sequencing, and differentially expressed genes, pathways, and affected cell types were determined. We observed extensive regulation of the IEC transcriptome with ∼4,000 genes significantly up-regulated, including key genes linked with epithelial barrier function. Enrichment of cell differentiation pathways was observed, along with an overrepresentation of stem cell marker genes, indicating an increase in the regenerative potential of the epithelial layer. In conclusion, B. breve UCC2003 plays a central role in driving intestinal epithelium homeostatic development during early life and suggests future avenues for next-stage clinical studies.

双歧杆菌在生命早期促进健康的潜在机制尚不清楚，特别是这种微生物群成员如何通过肠上皮细胞 (IEC) 的编程来调节肠道屏障。我们研究了短双歧杆菌UCC2003 对新生小鼠 IEC 转录组的影响。来自两周大的新生小鼠的小 IECs 被施用B .对 breve UCC2003 或 PBS（对照）进行全局 RNA 测序，并确定差异表达的基因、通路和受影响的细胞类型。我们观察到 IEC 转录组的广泛调控，约 4,000 个基因显着上调，包括与上皮屏障功能相关的关键基因。观察到细胞分化途径的富集以及干细胞标记基因的过度表达，表明上皮层再生潜力的增加。总之， B . breve UCC2003 在生命早期驱动肠上皮稳态发育中发挥着核心作用，并为下一阶段临床研究提出了未来途径。