Molecular mechanism of Escherichia coli-induced inflammatory response in vaginal epithelial cells using RNA-Seq analysis

Objective To investigate the molecular mechanism of inflammatory response in vaginal epithelial cells induced by Escherichia coli infection. Methods An inflammatory response model in vaginal epithelial cells stimulated by Escherichia coli was established. Then， differentially-expressed gene profiles between the control and Escherichia coli stimulation groups were obtained by RNA sequencing （RNA-Seq）. The enrichment signaling pathways of differentially-expressed genes were identified by bioinformatic analysis. The sequencing results were validated by quantitative fluorescent real-time PCR （RT-qPCR）. Results A total of 4899 differentially-expressed genes were found between the control and the Escherichia coli stimulation groups， including 1531 up-regulated genes and 3368 down-regulated genes. Gene Ontology （GO） showed that the functions of differentially-expressed genes were dominantly enriched in platelet-derived growth factor binding and co-receptor binding in the biological process term， endoplasmic reticulum chaperone complex in the cellular component term and protein folding in endoplasmic reticulum in the molecular functional term， respectively. Kyoto Encyclopedia of Genes and Genomes （KEGG） showed that these differentially-expressed genes were enriched in 39 signaling pathways， such as the NF-κB signaling pathway. The upregulation of differentially-expressed gene TNF-α was validated by RT-qPCR （P < 0.05）， which was consistent with the RNA-Seq results. Conclusion TNF-α regulating the NF-κB signaling pathway is a critical molecular mechanism of Escherichia coli-induced inflammatory response in vaginal epithelial cells.