Zika virus (ZIKV) crosses the placenta and causes congenital disease. Here we develop an animal model utilizing direct ZIKV inoculation into the uterine wall of pregnant, immunocompetent mice to evaluate transplacental transmission. Intrauterine inoculation at embryonic day (E) 10, but not E14, with African, Asian or American strains of ZIKV reduces fetal viability and increases infection of placental and fetal tissues. ZIKV inoculation at E10 causes placental inflammation, placental dysfunction and reduces neonatal brain cortical thickness, which is associated with increased activation of microglia. Viral antigen localizes in trophoblast and endothelial cells in the placenta, and endothelial, microglial and neural progenitor cells in the fetal brain. ZIKV infection of the placenta increases production of IFNβ and expression of IFN-stimulated genes 48 h after infection. This mouse model provides a platform for identifying factors at the maternal–fetal interface that contribute to adverse perinatal outcomes in a host with an intact immune system.
Preterm birth is a major risk factor for adverse neurological outcomes in ex-preterm children, including motor, cognitive, and behavioral disabilities. N-acetyl-L-cysteine therapy has been used in clinical studies; however, it requires doses that cause significant side effects. In this study, we explore the effect of low dose N-acetyl-L-cysteine therapy, delivered using a targeted, systemic, maternal, dendrimer nanoparticle (DNAC), in a mouse model of intrauterine inflammation. Our results demonstrated that intraperitoneal maternal DNAC administration significantly reduced the preterm birth rate and altered placental immune profile with decreased CD8+ T-cell infiltration. Furthermore, we demonstrated that DNAC improved neurobehavioral outcomes and reduced fetal neuroinflammation and long-term microglial activation in offspring. Our study is the first to provide evidence for the role of CD8+ T-cell in the maternal-fetal interface during inflammation and further support the efficacy of DNAC in preventing preterm birth and prematurity-related outcomes.
The P2X7 is an adenosine triphosphate (ATP)-gated ion channel involved in several facets of immune activation and neuronal function through its importance in interleukin (IL)-1β secretion. We hypothesized that blockade of P2X7 would prevent perinatal brain injury associated with exposure to intrauterine (IU) inflammation. Dams received 45 mg/kg of Brilliant Blue G (BBG), a specific P2X7 receptor (P2X7R) antagonist, on gestation day 17 (E17) prior to administration of lipopolysaccharide (LPS) or phosphate-buffered saline (PBS). Furthermore, we utilized embryo transfer experiments to delineate whether the P2X7 was the key mediator of IU inflammation-associated brain injury on maternal or fetal sides. In these experiments, P2X7–/– dams were embryo-transferred wild type embryos and wild type dams were embryo-transferred P2X7–/– embryos. In the mouse model of intrauterine inflammation, pharmacologic blockade of P2X7R reduced preterm birth rate, improved offspring performance on neuromotor tests as well as the dendritic arborization and density of cortical neurons. Embryo transfer experiments demonstrated the importance of maternal P2X7R in IU inflammation-mediated effects on offspring. Both genetic and pharmacologic blockade of IL-1β signaling, by targeting maternal P2X7R, ameliorated perinatal brain injury following exposure to IU inflammation. Specific targeting of maternal P2X7R may provide a clinically useful tool to prevent both preterm birth and prematurity-associated perinatal brain injury, and further studies are urgently needed.
4 December 2017 in American Journal of Reproductive Immunology
The modified 2-tier testing algorithm (MTTT) for Lyme disease (LD) has been approved by the US Food and Drug Administration. In this study, we show that the MTTT detected 28% more cases of early infection compared with the standard 2-tier algorithm while retaining high specificity in a region with a high incidence of LD.
Introduction: The Enterococcus genus is a common cause of nosocomial infections, with vancomycin-resistant enterococci (VRE) posing a significant treatment challenge. Method: This retrospective study, spanning ten years (2012 to 2021), analyzes antimicrobial susceptibility patterns of Enterococcus species from clinical samples in a Saudi Arabian tertiary care hospital. Result: A total of 1034 Enterococcus isolates were collected, 729 from general wards and 305 from intensive care unit (ICU) patients. VRE accounted for 15.9% of isolates. E. faecalis was the most common species (54.3% of isolates and 2.7% of VRE), followed by E. faecium (33.6% of isolates and 41.2% of VRE). E. faecium exhibited the highest resistance to ciprofloxacin (84.1%), ampicillin (81.6%), and rifampicin (80%), with daptomycin (0.6%) and linezolid (3.1%) showing the lowest resistance. In E. faecalis, ciprofloxacin resistance was highest (59.7%), followed by rifampicin (20.1%) and ampicillin (11.8%). Daptomycin (0%), linezolid (1.5%), and vancomycin (2.7%) had the lowest resistance. VRE cases had higher mortality rates compared to vancomycin-sensitive enterococci (VSE). Conclusion: Eight different strains of Enterocci were identified. E. faecalis was the most commonly identified strain, while E. faecium had the highest percentage of VRE. VRE cases had a significantly higher mortality rate than VSE cases.