Hepatic induction of cholesterol biosynthesis reflects a remote adaptive response to pneumococcal pneumonia
ABSTRACT: Transcriptional effects in liver, lung and blood samples from mice after intratracheal challenge with either Streptococcus pneumoniae serotype 19 (lobar-pneumonia) or serotype 2 (sepsis) were monitored after 6 and 24 hours and compared to sham (vehicle control). We gratefully acknowledge the BMBF grant within the “Promoting global research excellence in severe sepsis” (PROGRESS) study (01KI07111). Three tissues x two serotypes x two time resolved treatment groups x four replicates, three tissues x Sham Control x three replicates.
Project description:Transcriptional effects in liver, lung, spleen and blood samples from mice challenged to Sham and Sepsis by Peritoneal Contamination and Infection (PCI) were monitored after 6 and 24 hours 4 Tissues x 2 Time Resolved Treatment Groups x 4 Replicates, 4 Tissues x Sham Control x 3 Replicates
Project description:Transcriptional profiling of primary human alveolar macrophages (AMs) comparing control untreated AMs with AMs exposed with Serotype 14 Streptococcus pneumoniae (NCTC11902) strain (MOI 10) for 4 hours) Two-condition experiment, control AMs vs. infected AMs. Biological replicates: 3 control replicates, 3 infected replicates MOI 10.
Project description:Transcriptional effects in liver, lung and blood samples from mice after intratracheal challenge with either Streptococcus pneumoniae serotype 19 (lobar-pneumonia) or serotype 2 (sepsis) were monitored after 6 and 24 hours and compared to sham (vehicle control). We gratefully acknowledge the BMBF grant within the “Promoting global research excellence in severe sepsis” (PROGRESS) study (01KI07111). Overall design: Three tissues x two serotypes x two time resolved treatment groups x four replicates, three tissues x Sham Control x three replicates.
Project description:Background : The aim of this study is to improve our understanding of the mechanisms underlying the role of sepsis in the limb muscles of ICU patients with acute quadriplegic myopathy (AQM) by using a unique porcine ICU model, i.e., 5-day longitudinal experiments where animals are sedated, mechanically ventilated and exposed to factor triggering AQM that is endotoxin-induced sepsis. Results : An increased expression of genes involved in chemokine activity and transcriptional regulation. A decreased expression in genes regulating heat shock proteins, cytoskeletal & sarcomeric and oxidative stress response were also apparent. Therefore, it appears that sepsis has an additive deleterious role in acute quadriplegic myopathy. Sepsis-induced molecular mechanisms involving chemokine/innate immunity and heat shock proteins are forwarded as probable mechanisms underlying the decreased force generating capacity. Conclusions : This sepsis had significant effect on biceps femoris muscle force-generation capacity but not on fiber size. However, significant differences were observed between the MV and MV+SEP in the transcriptional regulation of an increased expression of genes involved in chemokine activity genes like MCP-1 and transcriptional regulation genes like JUNB, STAT3 and BHLHB2. A decreased expression in genes regulating heat shock proteins like HSP 90, HSP 70 and αB-crystallin, cytoskeletal & sarcomeric like MAP1A, MyBP-C1 and MYH7 and oxidative stress response like SRXN1 and SOD2 were also apparent. Therefore, it appears that sepsis has an additive negative role in acute quadriplegic myopathy. Four female domestic piglets (Sus scrofa, average body weight 25.5 kg) were used in this study. Piglets were immobilized by anesthesia and mechanically ventilated via a tracheotomy for a period of five days. During this study period, the animals were sedated using isoflurane inhalation (Abbott Laboratories, Chicago, Il, USA, 0.8 – 1.3% end-tidal concentration) supplemented by intravenous bolus doses of morphine and ketamine as needed. Core body temperature (blood) was maintained in the range of 38.5 – 40°C by a servo controlled heating pad. The animals received intravenous crystalloid fluid (Ringeracetat) to maintain stable blood pressure and urinary output and a glucose infusion (Rehydrex, Fresenius Kabi, Stockholm, Sweden, 25 mg glucose /mL) in the range of 0.5 – 1.5 mg/kg/minute to decrease the effects of catabolism. Each animal received prophylactic streptomycin 750 mg/d and bensylpenicillin 600 mg/d (Streptocillin Vet, Boeringer-Ingelheim, Hellerup, Denmark). Arterial blood gas analysis as well as electrolytes and blood glucose levels were monitored regularly and kept in the normal range throughout the study period. A neuromuscular blocking agent (NMBA) was administered as a continuous infusion of pancuronium bromide 0.1mg/kg/h (Pavolun; Organon, Boxtel, The Netherlands) for 5days while a corticosteroid (CS) was given as bolus doses of betamethasone 0.1 mg/kg (Betapred; GSK, Slona, Sweden) twice daily for 5days. Endotoxemia was induced by a continuous infusion of Escherichia coli endotoxin, serotype O26:B6 (Sigma Labkemi, Stockholm, Sweden) at 36 µg/kg/h for 1h. Key words : Treatment, immobilization, muscle function.
Project description:For Streptococcus pneumoniae, biofilms have been suggested to promote long-term colonization of the nasopharynx and contribute to the pathology of recurrent middle ear infections. To date numerous studies have investigated the contribution of specific genetic determinants for the development of pneumococcal biofilms, however, studies examining the global changes that occur during biofilm development and how they contribute to disease are lacking. Using Scanning and Transmission electron microscopy we examined development of a mature pneumococcal biofilm in a continuous flow through reactor. We determined that a mature biofilm is formed in discrete stages, is marked by the formation of complex 3-dimensional structures, and is primarily composed of dead pneumococci. Using genomic microarrays we determined that pneumococci in mature biofilms down regulate genes involved in protein synthesis, energy production, metabolism, capsular polysaccharide production, and virulence. We confirmed these changes by testing bacterial resistance to antimicrobials, measuring capsule production by ELSIA, and immunoblotting for pneumolysin production. We determined that biofilm pneumococci are hyper-adhesive, binding to cell lines at levels 9 to 11-fold greater than planktonic counterparts. Using Western blot and ELISA, we determined that biofilm bacteria produce greater amounts of the adhesins PsrP, CbpA, and surface exposed phosphorylcholine. We subsequently determined that the hyper-adhesive phenotype was in part due to selection of the transparent phase variant during biofilm growth. Intranasal, intratracheal and intraperitoneal challenge of mice with biofilm and planktonic pneumococci determined that biofilm bacteria were highly attenuated for invasive disease but not nasopharyngeal colonization. Immunization of mice with ethanol-killed biofilm pneumococci of serotype 4 conferred protection against challenge with same isolate but not a serotype 3. ELISA for reactive IgG levels subsequently determined that biofilm pneumococci do not provide high levels of cross-reactive protein antigens. Together these studies suggest that biofilms do not directly contribute to disease but instead confer a protected mode of growth for the pneumococcus. Pneumococcal biofilms compared to planktonic control at 4, 12, 24, 48 hours. 3 biological replicates each of 4 and 12 hour time points, and 2 biological replicates each of 24 and 48 hour time points. Flip dye (technical replicates) performed for 4, 12, and 24 hour time points; no technical replicate performed for 48 hour time point due to limiting material. Ratios were determined by averaging across technical and biological replicates. The following hybridizations made up each biological replicate: 14090167.tav.annot and 14090190.tav.annot (4hr biol rep 1); 14090169.tav.annot and 14090176.tav.annot (4hr biol rep 2); 14090192.tav.annot and 14090188.tav.annot (4hr biol rep 3); 14087688.tav.annot and 14090180.tav.annot (12hr biol rep 1); 14090185.tav.annot and 14090168.tav.annot (12hr biol rep 2); 14090191.tav.annot and 14090174.tav.annot (12hr biol rep 3); 14090170.tav.annot and 14090175.tav.annot (24hr biol rep 2); 14090193.tav.annot and 14087687.tav.annot (24hr biol rep 3); 14090181.tav.annot (48hr biol rep 1); 14090187.tav.annot (48hr biol rep 2)
Project description:Severe sepsis leads to massive activation of coagulation and complement cascades that could contribute to multiple organ failure (MOF) and death. To investigate the role of the complement and its crosstalk with the hemostatic system in the pathophysiology and therapeutics of sepsis, we have used a potent inhibitor (compstatin) administered early or late post E. coli challenge in a baboon model of sepsis-induced MOF. Microarray was used to study the affect of complement pathway on global gene expression pattern in sepsis, aims on exploring and discovering the new target genes as potential drugs for the early treatment and prevention of sepsis. Lung and liver tissues were obtained from three normal healthy animals (as Ctl), three animals challenged with sublethal dose of E. coli as SLEC, three animals treated with Compstatin at different sepsis stages after E.coli challenge as SLEC-CST0 and SLEC-CST5. All the animals challenged with E. coli were sacrified at 24 hours post challenge. Total RNAs were isolated from these tissues, hybridized with Affymetrix Human Genome GeneChip U133A 2.0.
Project description:Clinical study of critically ill patients with sepsis and sepsis-related ARDS with whole blood RNA collected within the first 24 hours of admission Goal of the study was to determine whether biologically relevant genes were identified to be differentially expressed genes in patients with sepsis alone and sepsis with ARDS Prospective observational study, case cohort design
Project description:Streptococcus (S.) pneumoniae is the most frequently isolated causative pathogen community-acquired pneumonia, a leading cause of mortality worldwide. We investigated the role of the inflammasome sensor NLRP3 and the inflammasome adapter ASC during S. pneumoniae pneumonia. Detailed analysis of the early inflammatory response in the lung by whole genome transcriptional profiling, we identified several mediators that were differentially expressed between Nlrp3-/- and Asc-/ - mice. WT, Nlrp3- and Asc-deficient mice were intranasally inocculated with Streptococcus pneumoniae D39 and ATCC6303 both at high and low dose. Lung homogenates were harvested and gene expression profiling was performed.
Project description:Neonates manifest a unique host response to sepsis even among other children. Preterm neonates may experience sepsis soon after birth or during often protracted birth hospitalizations as they attain physiologic maturity. We examined the transcriptome using genome-wide expression profiling on prospectively collected peripheral blood samples from infants evaluated for sepsis within 24 hours after clinical presentation. Simultaneous plasma samples were examined for alterations in inflammatory mediators. Group designation (sepsis or uninfected) was determined retrospectively based on clinical exam and laboratory results over the next 72 hours from the time of evaluation. Unsupervised analysis showed the major node of separation between groups was timing of sepsis episode relative to birth (early, <3 days or late, >3 days). Principal component analyses revealed significant differences between patients with early or late sepsis despite the presence of similar key immunologic pathway aberrations in both groups. Unique to neonates, the uninfected state and host response to sepsis is significantly affected by timing relative to birth. Future therapeutic approaches may need to be tailored to the timing of the infectious event based on post-natal age. We used human microarrays to detail the molecular profile of the events that occur following sepsis in hospitalized neonates Please note that 'uninfected chorio' represents babies who were not infected but had chorioamnionitis exposure
Project description:Alterations in global transcriptional profiles of S. pneumoniae 6304 serotype 4 after 50 passages (50P) and 100 passages (100P) on laboratory media Keywords: Adaptation to unique growth environment Three conditions experiment: Control, single passage strain (1P), 2 biological replicates Experimental 50 passage strain (50P), 2 biological replicates Experimental 100 passage strain (100P), 2 biological replicates All strains independently grown and harvested at OD600 ~ 0.5. Four spot replicates per array.