Milking the niche: Microbial control of neonatal hematopoiesis.

Howard et al. report in Cell that osteopontin, a glycoprotein in milk, shapes the neonatal microbiome in a way that regulates hematopoiesis. The work shows this pathway promotes dendritic cell development and protects newborns from severe respiratory infection, linking maternal milk and microbiota to early immune development. The findings point to a nutrition-to-immunity pathway relevant to long-term disease susceptibility.