Molecular characteristics of the protective effect of Bacillus Calmette-Guerin against neonatal sepsis

Abstract

Purpose: To investigate the molecular characteristics and potential mechanisms underlying the immune-protective effect of Bacillus Calmette-Guerin (BCG) against neonatal sepsis (NS). Methods: Data on transcriptome sequencing of BCG infection, NS, post-BCG infection sepsis, and the respective controls were retrieved from public databases. Systems biology screening was used to identify differentially expressed genes (DEGs) amongst the groups, and common DEGs with high connectivity were selected using protein-protein interaction network analysis. Results: A total of 15 common DEGs were related to the expressions of macrophages and neutrophils after BCG infection and NS infection. Some of the genes were involved in IL-4/IL-13 signal pathway and neutrophil degranulation pathway, and they were highly correlated with the expressions of TNF-alpha, IL-6 and type I interferon-response signal pathway. This may reduce the poor prognosis of NS after BCG infection. Conclusion: These findings provide insights into how BCG-induced trained immunity may provide protection against NS.