Gastric Infection by Cronobacter sakazakii: An In Vitro Insight.

Abstract

Cronobacter sakazakii, an opportunistic foodborne pathogen associated with powdered infant formula, causes severe neonatal infections, yet its interaction with gastric epithelial cells remains poorly characterized. Here, we conducted a preliminary in vitro study to evaluate early host-pathogen responses of C. sakazakii in AGS gastric epithelial cells. AGS cells were exposed to C. sakazakii ATCC 29544 at a multiplicity of infection of 100 for 2 h, and cytotoxicity and transcriptional responses were assessed by viability assay, gentamicin protection assay, and reverse transcription-quantitative polymerase chain reaction. Infection significantly reduced AGS cell viability and increased expression of bacterial virulence-associated genes (ompA and hfq) and host inflammatory genes (IL-8 and NF-ƙB) compared with mock-infected controls (p < 0.001). Gentamicin-protected recovery was consistent with bacterial entry into AGS cells, although confirmatory imaging-based analyses were not performed. These findings indicate that C. sakazakii (ATCC 29544) can elicit early cytotoxic and pro-inflammatory responses in AGS gastric epithelial cells under in vitro conditions, supporting the need for confirmatory studies in more physiologically relevant gastric study models.