Project description:Necrotizing enterocolitis (NEC) is an acute and life-threatening gastrointestinal disorder afflicting preterm infants, which is currently unpreventable. Fecal microbiota transplantation (FMT) is a promising preventative therapy, but potential bacterial infection raise concern. Removal of bacteria from donor feces may reduce this risk while maintaining the NEC-preventive effects. We aimed to assess preclinical efficacy and safety of bacteria-free fecal filtrate transfer (FFT). Using fecal material from healthy suckling piglets, we administered FMT rectally, or cognate FFT either rectally or oro-gastrically to formula-fed preterm, cesarean-delivered piglets as a model for preterm infants, We compared gut pathology and related safety parameters with saline controls, and analyzed ileal mucosal transcriptome to gauge the host e response to FMT and FFT treatments relative to control. Results showed that oro-gastric FFT prevented NEC, whereas FMT did not perform better than control. Moreover, FFT but not FMT reduced intestinal permeability, whereas FMT animals had reduced body weight increase and intestinal growth. Global gene expression of host mucosa responded to FMT but not FFT with increased and decreased bacterial and viral defense mechanisms, respectively. In conclusion, as preterm infants are extremely vulnerable to enteric bacterial infections, rational NEC-preventive strategies need incontestable safety profiles. Here we show in a clinically relevant animal model that FFT, as opposed to FMT, efficiently prevents NEC without any recognizable side effects. If translatable to preterm infants, this could lead to a change of practice and in turn a reduction in NEC burden.
Project description:Neonatal necrotizing enterocolitis (NEC) is a deadly and unpredictable gastrointestinal disease, for which no biomarkers exist. We aimed to describe the methylation patterns in stool and colon from infants with NEC.
Project description:Total DNA was extracted from stool specimens, amplified to collect amplicons of variable V3–V4 regions of the bacterial 16s rRNA gene and sequenced with MiSeq (2x300bp) Illumina platform.
Project description:Development of the gut microbiota is greatly impacted in preterm infants. Despite increasing knowledge about microbiota composition in preterm infants, knowledge about the functional signatures of the intestinal microbiota remains limited. The aim was to study transitions in microbiota activity during the first six postnatal weeks in ten preterm infants. A total of 64 stool samples were measured by LC-MS/MS.
Project description:Gut microbiota were assessed in 540 colonoscopy-screened adults by 16S rRNA gene sequencing of stool samples. Investigators compared gut microbiota diversity, overall composition, and normalized taxon abundance among these groups.
Project description:Necrotizing enterocolitis (NEC), a serious gastrointestinal disease that afflicts 5-10% of preterm infants, often progresses rapidly from mild food intolerance into extensive haemorrhage, inflammation and necrosis. Events leading to NEC have remained poorly defined. Similar disease characteristics are observed in preterm pigs 24-48 h after feeding formula. Using this model, we aimed to characterize the temporal development of NEC, and describe the functional and immunological response of the preterm intestine preceding NEC. Keywords: time course
Project description:Most hospitalized preterm infants receive antibiotics (AB) in the first days of life to treat or prevent systemic infections. Short-term, early AB treatment may also prevent against the microbiota-dependent serious gut disorder, necrotising enterocolitis (NEC). However, it remains a challenge to predict or early detection of NEC in the first weeks of life and few diagnostic markers exist. Using preterm piglets as models for infants, we hypothesised that proteomic profiling could be used to identify new early plasma biomarkers of NEC with or without prior AB treatment. Preterm newborn pigs were treated with saline (CON) or antibiotics (ampicillin, gentamicin, and metronidazole), given enterally (ENT) or parenterally (PAR), and fed formula for four days to induce NEC. The gut was collected for scoring of NEC lesions and blood was collected for haematology and plasma proteomics
Project description:Necrotizing enterocolitis (NEC) is the most common and lethal gastrointestinal disease affecting preterm infants. NEC develops suddenly and is characterized by gut barrier destruction, an inflammatory response, intestinal necrosis and multi-system organ failure. There is currently no method for early NEC detection, and the pathogenesis of NEC remains unclear.
Project description:This study aimed to investigate the potential of fecal proteomics signatures for NEC prediction. Stools were collected from NEC infants up to 10 days before their diagnosis and matched with those from non-NEC controls for three tested periods. Stool samples were analyzed with liquid chromatography-tandem mass spectrometry using SWATH acquisition and a cross-compatible proteomic software platform to perform label-free quantification. ROC curves and principal component analysis were used to explore discriminating information provided by potential markers and sets of markers were evaluated with classical clustering and classification methods to evaluate their capacity to sort the samples giving to their actual outcomes. We identified a specific series of markers that predicted all NEC from non-NEC infants at least a week in advance. Our study shows that multiplexed proteomic signature detection constitutes a favorable approach for the early detection of NEC.
Project description:Bacillus Calmette–Guérin (BCG) vaccination immediately after birth provides overall protection against immune disorders in healthy infants. However, for vulnerable infants such as preterm or low birth weights, delayed BCG vaccination is usually recommended. The mechanism underlying this clinical application remains obscure. Here we reported that BCG vaccination abrogated the transitory appearance of immunosuppressive myeloid cells in neonatal mice, that is myeloid-derived suppressor cells (MDSCs) represented as the important immunoprotection against inflammatory diseases in early life. A combination of single-cell transcriptome, metabolite profiling, and functional analysis revealed that the upregulation of mTOR/HIF1a signaling and the enhanced glycolysis explained the underlying mechanism. Consequently, BCG vaccination significantly exacerbated the severity of necrotizing enterocolitis (NEC), a common clinical emergency primarily affecting preterm or low birth weight infants. Adoptive transfer of MDSCs or pharmalogical inhibition of glycolysis or mTOR signaling efficiently relieved the severity of NEC upon BCG vaccination. These observations suggest that BCG may diminish the protective mechanism of myeloid cells and enhances the susceptibility of NEC in vulnerable neonates.