Project description:Neonatal meningitis caused by Escherichia coli (NMEC) is a leading cause of morbidity and mortality in newborns, and its pathogenesis relies on the ability of the bacterium to adapt and survive in diverse host environments. Despite advances in neonatal care, significant gaps remain in our understanding of how NMEC reprogram their transcriptome to survive in physiologically relevant niches. This study investigated the transcriptomic profiles of E. coli strain RS218 (O18:H7:K1) in four under host-relevant environment —colonic fluid (CF), serum (S), human brain endothelial cells (HBECs) and cerebrospinal fluid (CSF)—to mimic the infection landscape of neonatal meningitis. High-throughput RNA sequencing (RNA-seq) was performed to profile NMEC’s transcriptomic responses in each niche, and differential gene expression analyses were conducted to identify enriched pathways.
Project description:Neonatal bacterial meningitis is a leading cause of infant morbidity and mortality, yet the molecular and cellular basis of the leptomeningeal response to infection remains poorly defined. Here, we study a mouse model of neonatal E. coli meningitis, combining conditional gene knockouts, leptomeningeal single-nucleus RNA sequencing, and endothelial cell culture to explore the role of Toll-like receptor 4 (TLR4) signaling in the host response to infection. Deletion of Tlr4 in non-myeloid cells dramatically reduced the inflammatory response in all leptomeningeal cell types and abrogated the infection-associated increase in vascular permeability. In a brain endothelial cell line (bEnd.3 cells), exposure to E. coli triggered NF-κB activation, selective internalization of Claudin-5, and increased monolayer permeability, responses that were eliminated by Tlr4 knockout. RNA-seq showed that TLR4 controls an NF-κB–driven transcriptional program that orchestrates the endothelial response to E. coli. These findings reveal multiple TLR4-dependent host responses to neonatal Gram-negative bacterial meningitis.
Project description:Preterm birth is currently the leading cause of neonatal morbidity and mortality. Genetic, immunological and infectious causes are suspected. Preterm infants have a higher risk of severe bacterial neonatal infections, most of which are caused by Escherichia coli an in particular E. coli K1strains. Women with history of preterm delivery have a high risk of recurrence and therefore constitute a target population for the development of vaccine against E. coli neonatal infections. Here, we characterized the immunological, microbiological and protective properties of a live attenuated vaccine candidate in adult female mice and their pups against after a challenge by K1 and non-K1 strains of E. coli. Our results show that the E. coli K1 E11 aroA vaccine induces strong immunity, driven by polyclonal bactericidal antibodies. In our model of meningitis, pups born to mothers immunized before mating were well protected against various K1 and non-K1 strains of E. coli. Given the very high mortality rate and the neurological sequalae associated with neonatal E. coli K1 meningitis, our results constitute preclinical proof of concept for the development of a live attenuated vaccine against severe E. coli infections in women at risk of preterm delivery.
2024-01-02 | GSE252194 | GEO
Project description:Sequencing of Streptococcus pneumoniae variants causing meningitis
Project description:Cronobacter (C.) is an important emerging opportunistic foodborne pathogen representing significant cause of mortality in neonatal patients with bacteremia and meningitis. Knowledge on the pathobiology of Cronobacter mediated meningitis has to a large extend been explored using in vitro models. To explore the innate immune response against the neonatal sepsis/meningitis causing isolate C. turicensis z3032 in vivo, zebrafish larvae (Danio rerio) were used as infection model. Following establishment of infection in zebrafish larvae with z3032, dual RNA-sequencing of host-pathogen was undertaken to profile RNA expression simultaneously in the pathogen and the head region of the zebrafish host.
Project description:Cronobacter (C.) is an important emerging opportunistic foodborne pathogen representing significant cause of mortality in neonatal patients with bacteremia and meningitis. Knowledge on the pathobiology of Cronobacter mediated meningitis has to a large extend been explored using in vitro models. To explore the innate immune response against the neonatal sepsis/meningitis causing isolate C. turicensis z3032 in vivo, zebrafish larvae (Danio rerio) were used as infection model. Following establishment of infection in zebrafish larvae with z3032, dual RNA-sequencing of host-pathogen was undertaken to profile RNA expression simultaneously in the pathogen and the head region of the zebrafish host.
2024-06-28 | GSE236313 | GEO
Project description:Genome of Escherichia coli strains of serotype O1:K1 causing neonatal meningitis in France