Neonatal infection induces long-lasting dysbiosis of the gut microbiota in a mouse model.

Early life is a "critical window" for gut microbiota development, antibiotic use during this period exerts a profound effect on gut microbial dysbiosis and asthma. In clinical practice, antibiotics are usually used in patients with bacterial infections, we previously showed that neonatal pneumonia promoted adult-onset asthma in mice model, while it remains unclear whether neonatal infection have long-term effects on gut microbiota. Neonatal BALB/c mice were inoculated with 5*10 CFU D39 to establish non-lethal pneumonia model. At 2, 3, 8 weeks of age, feces in the cecum were prepared for 16S rRNA sequencing, lungs were collected for histopathologic and lung function analysis. -infected neonatal mice exhibited histopathologic lesions in their lungs and increased airway hyperresponsiveness, obvious alterations in alpha and beta diversities in the entire gut microbiota, and changes of the community structure during the breastfeeding period, infancy, and adulthood. Furthermore, gut microbial composition was modified after neonatal infection, with a decreased relative abundance of Lactobacillus in the breastfeeding period and infancy; in adulthood, the relative abundance of Allobaculum diminished while that of Proteobacteria was augmented. Neonatal infection induced a long-term alteration in microbial community composition.