Identification of a functional peptide of a probiotic bacterium-derived protein for the sustained effect on preventing colitis.

Several probiotic-derived factors have been identified as effectors of probiotics for exerting beneficial effects on the host. However, there is a paucity of studies to elucidate mechanisms of their functions. p40, a secretory protein, is originally isolated from a probiotic bacterium, Lactobacillus rhamnosus GG. Thus, this study aimed to apply structure-functional analysis to define the functional peptide of p40 that modulates the epigenetic program in intestinal epithelial cells for sustained prevention of colitis. In silico analysis revealed that p40 is composed of a signal peptide (1-28 residues) followed by a coiled-coil domain with uncharacterized function on the N-terminus, a linker region, and a ß-sheet domain with high homology to CHAP on the C-terminus. Based on the p40 three-dimensional structure model, two recombinant p40 peptides were generated, p40N120 (28-120 residues) and p40N180 (28-180 residues) that contain first two and first three coiled coils, respectively. Compared to full-length p40 (p40F) and p40N180, p40N120 showed similar or higher effects on up-regulating expression of Setd1b (encoding a methyltransferase), promoting mono- and trimethylation of histone 3 on lysine 4 (H3K4me1/3), and enhancing Tgfb gene expression and protein production that leads to SMAD2 phosphorylation in human colonoids and a mouse colonic epithelial cell line. Furthermore, supplementation with p40F and p40N120 in early life increased H3K4me1, Tgfb expression and differentiation of regulatory T cells (Tregs) in the colon, and mitigated disruption of epithelial barrier and inflammation induced by DSS in adult mice. This study reveals the structural feature of p40 and identifies a functional peptide of p40 that could maintain intestinal homeostasis.

Feasibility trial for the management of severe acute malnutrition in older children with sickle cell anemia in Nigeria.

Children with sickle cell anemia (SCA) living in Nigeria are at an increased risk of malnutrition, which contributes to increased morbidity and mortality. However, evidence-based guidelines for managing malnutrition in children with SCA are lacking. To address this gap, we conducted a multicenter, randomized controlled feasibility trial to assess the feasibility and safety of treating children with SCA aged from 5 to 12 years and having uncomplicated severe acute malnutrition (body mass index z score of <-3.0). Children with SCA and uncomplicated severe acute malnutrition were randomly allocated to receive supplemental ready-to-use therapeutic food (RUTF) with or without moderate-dose hydroxyurea therapy (20 mg/kg per day). Over a 6-month enrollment period, 3190 children aged from 5 to 12 years with SCA were evaluated for eligibility, and 110 of 111 children who were eligible were enrolled. During the 12-week trial, no participants withdrew or missed visits. One participant died of unrelated causes. Adherence was high for hydroxyurea (94%, based on pill counts) and RUTF (100%, based on the number of empty sachets returned). No refeeding syndrome event or hydroxyurea-related myelosuppression occurred. At the end of the trial, the mean change in body mass index z score was 0.49 (standard deviation = 0.53), and 39% of participants improved their body mass index z score to ≥-3.0. Our findings demonstrate the feasibility, safety, and potential of outpatient treatment for uncomplicated severe acute malnutrition in children with SCA aged from 5 to 12 years in a low-resource setting. However, RUTF sharing with household and community members potentially confounded the response to malnutrition treatment. This trial was registered at clinicaltrials.gov as #NCT03634488.

Fecal transplantation for treatment of inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic, relapsing disease of the gastrointestinal (GI) tract that is thought to be associated with a complex interplay between the immune system, the GI tract lining, the environment, and the gut microbiome, leading to an abnormal inflammatory response in genetically susceptible individuals. An altered composition of the gut's native microbiota, known as dysbiosis, may have a major role in the pathogenesis of ulcerative colitis (UC) and Crohn disease (CD), two subtypes of IBD. There is growing interest in the correction of this underlying dysbiosis using fecal microbiota transplantation (FMT). OBJECTIVES: To evaluate the benefits and safety profile of FMT for treatment of IBD in adults and children versus autologous FMT, placebo, standard medication, or no intervention. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, two clinical trial registries, and the reference sections of published trials through 22 December 2022. SELECTION CRITERIA: We included randomized controlled trials that studied adults and children with UC or CD. Eligible intervention arms used FMT, defined as the delivery of healthy donor stool containing gut microbiota to a recipient's GI tract, to treat UC or CD. DATA COLLECTION AND ANALYSIS: Two review authors independently screened studies for inclusion. Our primary outcomes were: 1. induction of clinical remission, 2. maintenance of clinical remission, and 3. serious adverse events. Our secondary outcomes were: 4. any adverse events, 5. endoscopic remission, 6. quality of life, 7. clinical response, 8. endoscopic response, 9. withdrawals, 10. inflammatory markers, and 11. microbiome outcomes. We used the GRADE approach to assess the certainty of evidence. MAIN RESULTS: We included 12 studies with 550 participants. Three studies were conducted in Australia; two in Canada; and one in each of the following: China, the Czech Republic, France, India, the Netherlands, and the USA. One study was conducted in both Israel and Italy. FMT was administered in the form of capsules or suspensions and delivered by mouth, nasoduodenal tube, enema, or colonoscopy. One study delivered FMT by both oral capsules and colonoscopy. Six studies were at overall low risk of bias, while the others had either unclear or high risk of bias. Ten studies with 468 participants, of which nine studies focused on adults and one focused on children, reported induction of clinical remission in people with UC at longest follow-up (range 6 to 12 weeks) and showed that FMT may increase rates of induction of clinical remission in UC compared to control (risk ratio (RR) 1.79, 95% confidence interval (CI) 1.13 to 2.84; low-certainty evidence). Five studies showed that FMT may increase rates of induction of endoscopic remission in UC at longest follow-up (range 8 to 12 weeks); however, the CIs around the summary estimate were wide and included a possible null effect (RR 1.45, 95% CI 0.64 to 3.29; low-certainty evidence). Nine studies with 417 participants showed that FMT may result in little to no difference in rates of any adverse events (RR 0.99, 95% CI 0.85 to 1.16; low-certainty evidence). The evidence was very uncertain about the risk of serious adverse events (RR 1.77, 95% CI 0.88 to 3.55; very low-certainty evidence) and improvement in quality of life (mean difference (MD) 15.34, 95% CI -3.84 to 34.52; very low-certainty evidence) when FMT was used to induce remission in UC. Two studies, of which one also contributed data for induction of remission in active UC, assessed maintenance of remission in people with controlled UC at longest follow-up (range 48 to 56 weeks). The evidence was very uncertain about the use of FMT for maintenance of clinical remission (RR 2.97, 95% CI 0.26 to 34.42; very low-certainty evidence) and endoscopic remission (RR 3.28, 95% CI 0.73 to 14.74; very low-certainty evidence). The evidence was also very uncertain about the risk of serious adverse events, risk of any adverse events, and improvement in quality of life when FMT was used to maintain remission in UC. None of the included studies assessed use of FMT for induction of remission in people with CD. One study with 21 participants reported data on FMT for maintenance of remission in people with CD. The evidence was very uncertain about the use of FMT for maintenance of clinical remission in CD at 24 weeks (RR 1.21, 95% CI 0.36 to 4.14; very low-certainty evidence). The evidence was also very uncertain about the risk of serious or any adverse events when FMT was used to maintain remission in CD. None of the studies reported data on use of FMT for maintenance of endoscopic remission or improvement in quality of life in people with CD. AUTHORS' CONCLUSIONS: FMT may increase the proportion of people with active UC who achieve clinical and endoscopic remission. The evidence was very uncertain about whether use of FMT in people with active UC impacted the risk of serious adverse events or improvement in quality of life. The evidence was also very uncertain about the use of FMT for maintenance of remission in people with UC, as well as induction and maintenance of remission in people with CD, and no conclusive statements could be made in this regard. Further studies are needed to address the beneficial effects and safety profile of FMT in adults and children with active UC and CD, as well as its potential to promote longer-term maintenance of remission in UC and CD.

Fecal microbiota transplantation for the treatment of recurrent Clostridioides difficile (Clostridium difficile).

BACKGROUND: Clostridioides difficile (formerly known as Clostridium difficile) is a bacterium that can cause potentially life-threatening diarrheal illness in individuals with an unhealthy mixture of gut bacteria, known as dysbiosis, and can cause recurrent infections in nearly a third of infected individuals. The traditional treatment of recurrent C difficile infection (rCDI) includes antibiotics, which may further exacerbate dysbiosis. There is growing interest in correcting the underlying dysbiosis in rCDI using of fecal microbiota transplantation (FMT); and there is a need to establish the benefits and harms of FMT for the treatment of rCDI based on data from randomized controlled trials. OBJECTIVES: To evaluate the benefits and harms of donor-based fecal microbiota transplantation for the treatment of recurrent Clostridioides difficile infection in immunocompetent people. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 31 March 2022. SELECTION CRITERIA: We considered randomized trials of adults or children with rCDI for inclusion. Eligible interventions must have met the definition of FMT, which is the administration of fecal material containing distal gut microbiota from a healthy donor to the gastrointestinal tract of a person with rCDI. The comparison group included participants who did not receive FMT and were given placebo, autologous FMT, no intervention, or antibiotics with activity against C difficile. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. proportion of participants with resolution of rCDI and 2. serious adverse events. Our secondary outcomes were 3. treatment failure, 4. all-cause mortality, 5. withdrawal from study, 6. rate of new CDI infection after a successful FMT, 7. any adverse event, 8. quality of life, and 9. colectomy. We used the GRADE criteria to assess certainty of evidence for each outcome. MAIN RESULTS: We included six studies with 320 participants. Two studies were conducted in Denmark, and one each in the Netherlands, Canada, Italy, and the US. Four were single-center and two were multicenter studies. All studies included only adults. Five studies excluded people who were severely immunocompromised, with only one study including 10 participants who were receiving immunosuppressive therapy out of the 64 enrolled; these were similarly distributed between the FMT arm (4/24 or 17%) and comparison arms (6/40 or 15%). The route of administration was the upper gastrointestinal tract via a nasoduodenal tube in one study, two studies used enema only, two used colonoscopic only delivery, and one used either nasojejunal or colonoscopic delivery, depending on a clinical determination of whether the recipient could tolerate a colonoscopy. Five studies had at least one comparison group that received vancomycin. The risk of bias (RoB 2) assessments did not find an overall high risk of bias for any outcome. All six studies assessed the efficacy and safety of FMT for the treatment of rCDI. Pooled results from six studies showed that the use of FMT in immunocompetent participants with rCDI likely leads to a large increase in resolution of rCDI in the FMT group compared to control (risk ratio (RR) 1.92, 95% confidence interval (CI) 1.36 to 2.71; P = 0.02, I2 = 63%; 6 studies, 320 participants; number needed to treat for an additional beneficial outcome (NNTB) 3; moderate-certainty evidence). Fecal microbiota transplantation probably results in a slight reduction in serious adverse events; however, the CIs around the summary estimate were wide (RR 0.73, 95% CI 0.38 to 1.41; P = 0.24, I² = 26%; 6 studies, 320 participants; NNTB 12; moderate-certainty evidence). Fecal microbiota transplantation may result in a reduction in all-cause mortality; however, the number of events was small, and the CIs of the summary estimate were wide (RR 0.57, 95% CI 0.22 to 1.45; P = 0.48, I2 = 0%; 6 studies, 320 participants; NNTB 20; low-certainty evidence). None of the included studies reported colectomy rates. AUTHORS' CONCLUSIONS: In immunocompetent adults with rCDI, FMT likely leads to a large increase in the resolution of recurrent Clostridioides difficile infection compared to alternative treatments such as antibiotics. There was no conclusive evidence regarding the safety of FMT for the treatment of rCDI as the number of events was small for serious adverse events and all-cause mortality. Additional data from large national registry databases might be required to assess any short-term or long-term risks with using FMT for the treatment of rCDI. Elimination of the single study that included some immunocompromised people did not alter these conclusions. Due to the low number of immunocompromised participants enrolled, conclusions cannot be drawn about the risks or benefits of FMT for rCDI in the immunocompromised population.

Development and Validation of Web-Based Tool to Predict Lamina Propria Fibrosis in Eosinophilic Esophagitis.

INTRODUCTION: Approximately half of esophageal biopsies from patients with eosinophilic esophagitis (EoE) contain inadequate lamina propria, making it impossible to determine the lamina propria fibrosis (LPF). This study aimed to develop and validate a web-based tool to predict LPF in esophageal biopsies with inadequate lamina propria. METHODS: Prospectively collected demographic and clinical data and scores for 7 relevant EoE histology scoring system epithelial features from patients with EoE participating in the Consortium of Eosinophilic Gastrointestinal Disease Researchers observational study were used to build the models. Using the least absolute shrinkage and selection operator method, variables strongly associated with LPF were identified. Logistic regression was used to develop models to predict grade and stage of LPF. The grade model was validated using an independent data set. RESULTS: Of 284 patients in the discovery data set, median age (quartiles) was 16 (8-31) years, 68.7% were male patients, and 93.4% were White. Age of the patient, basal zone hyperplasia, dyskeratotic epithelial cells, and surface epithelial alteration were associated with presence of LPF. The area under the receiver operating characteristic curve for the grade model was 0.84 (95% confidence interval: 0.80-0.89) and for stage model was 0.79 (95% confidence interval: 0.74-0.84). Our grade model had 82% accuracy in predicting the presence of LPF in an external validation data set. DISCUSSION: We developed parsimonious models (grade and stage) to predict presence of LPF in esophageal biopsies with inadequate lamina propria and validated our grade model. Our predictive models can be easily used in the clinical setting to include LPF in clinical decisions and determine its effect on treatment outcomes.

Clinical Hypnosis in Pediatric Crohn's Disease: A Randomized Controlled Pilot Study.

OBJECTIVE: The aim of this study was to implement clinical hypnosis (CH) as an adjunctive therapy for adolescents with Crohn's disease (CD) and to assess the impact of CH on quality of life (QoL), abdominal pain, psychosocial measures, and disease activity compared with standard care. METHODS: Forty adolescents with CD were randomized to a hypnosis intervention (HI) or waitlist control (WC) group. The intervention consisted of 1 in-person CH session, self-hypnosis education, and recordings for home practice. Data was collected at baseline, after the 8-week intervention, and at week 16. The primary outcome was patient- and parent-reported QoL; secondary outcomes were patient-reported abdominal pain, depression, anxiety, and sleep; school absences; and disease activity by Pediatric Crohn's Disease Activity Index. Paired and independent t-tests were used to compare differences from baseline to postintervention within and between groups. RESULTS: Forty patients (50% girls, mean 15.8 years) were enrolled from February to May 2019. Seventy-eight percent had inactive disease, and 55% had abdominal pain. Post intervention, significant improvements were noted in HI parent-reported QoL compared with WC in total score (P = 0.05), social functioning (P = 0.01), and school functioning (P = 0.04) but patient-reported QoL was unchanged. Abdominal pain severity significantly improved in HI compared with WC (P = 0.03). School absences decreased in significantly more intervention than control patients (P = 0.01). Patients who practiced self-hypnosis consistently showed a trend toward greater QoL improvement than those who did not (P = 0.1). CONCLUSIONS: CH is an acceptable and feasible adjunct in CD and may improve psychosocial QoL and abdominal pain. Further research is warranted.

Exposure to p40 in Early Life Prevents Intestinal Inflammation in Adulthood Through Inducing a Long-Lasting Epigenetic Imprint on TGFß.

BACKGROUND & AIMS: Colonization by gut microbiota in early life confers beneficial effects on immunity throughout the host's lifespan. We sought to elucidate the mechanisms whereby neonatal supplementation with p40, a probiotic functional factor, reprograms intestinal epithelial cells for protection against adult-onset intestinal inflammation. METHODS: p40 was used to treat young adult mouse colonic (YAMC) epithelial cells with and without deletion of a methyltransferase, su(var)3-9, enhancer-of-zeste and trithorax domain-containing 1ß (Setd1ß), and mice in early life or in adulthood. Anti-transforming growth factor ß (TGFß)-neutralizing antibodies were administered to adult mice with and without colitis induced by 2,4,6-trinitrobenzenesulfonic acid or dextran sulfate sodium. We examined Setd1b and Tgfb gene expression, TGFß production, monomethylation and trimethylation of histone H3 on the lysine 4 residue (H3K4me1/3), H3K4me3 enrichment in Tgfb promoter, differentiation of regulatory T cells (Tregs), and the inflammatory status. RESULTS: p40 up-regulated expression of Setd1b in YAMC cells. Accordingly, p40 enhanced H3K4me1/3 in YAMC cells in a Setd1ß-dependent manner. p40-regulated Setd1ß mediated programming the TGFß locus into a transcriptionally permissive chromatin state and promoting TGFß production in YAMC. Furthermore, transient exposure to p40 during the neonatal period and in adulthood resulted in the immediate increase in Tgfb gene expression. However, only neonatal p40 supplementation induced the sustained H3K4me1/3 and Tgfb gene expression that persisted into adulthood. Interfering with TGFß function by neutralizing antibodies diminished the long-lasting effects of neonatal p40 supplementation on differentiation of Tregs and protection against colitis in adult mice. CONCLUSIONS: Exposure to p40 in early life enables an epigenetic imprint on TGFß, leading to long-lasting production of TGFß by intestinal epithelial cells to expand Tregs and protect the gut against inflammation.

Factors Associated With Adequate Lamina Propria Sampling and Presence of Lamina Propria Fibrosis in Children with Eosinophilic Esophagitis.

BACKGROUND & AIMS: Esophageal biopsies in children with eosinophilic esophagitis (EoE) are often inadequate for assessment of lamina propria and lamina propria fibrosis (LPF). For children with EoE, little is known about the factors associated with adequate lamina propria (aLP) sampling or the relationship among epithelial features in esophageal biopsies with and without LPF. We aimed to evaluate aLP in esophageal biopsies from children with and without EoE, identify factors associated with aLP and LPF, and examine the relationship among epithelial features in biopsies with and without LPF in children with EoE. METHODS: In a retrospective study, we analyzed clinical, endoscopic, and histologic data from 217 children (124 with EoE and 94 without EoE [controls]) using descriptive statistics, logistic regression, Spearman's correlation, and receiver operating characteristic curve analysis. Active and inactive EoE were defined per the 2011 consensus guidelines. RESULTS: aLP was observed in biopsies from higher proportion of children with EoE (69%) than controls (31%) (P = .0001). Active EoE was independently associated with aLP (adjusted odds ratio [aOR], 4.23; 95% CI, 1.00-18.13; P = .05). Patient sex (aOR for boys, 8.37; 95% CI, 1.23-56.74; P = .03) and peak eosinophil count (aOR, 1.02; 95% CI, 1.01-1.04; P = .01) were independently associated with LPF. Epithelial features were strongly interrelated in biopsies with LPF, and the presence of specific epithelial features was associated with LPF. CONCLUSIONS: aLP was observed in a higher proportion of esophageal biopsies from children with EoE than controls. EoE status, patient sex, and peak eosinophil count were associated with aLP sampling and LPF. Given the intricate relationship between epithelial features and LPF, computational models can be developed to identify children with esophageal biopsies without aLP who are at risk for LPF.

Novel Insights Into Tissue-Specific Biochemical Alterations in Pediatric Eosinophilic Esophagitis Using Raman Spectroscopy.

INTRODUCTION: Elucidating esophageal biochemical composition in eosinophilic esophagitis (EoE) can offer novel insights into its pathogenesis, which remains unclear. Using Raman spectroscopy, we profiled and compared the biochemical composition of esophageal samples obtained from children with active (aEoE) and inactive EoE (iEoE) with non-EoE controls, examined the relationship between spectral markers and validated EoE activity indices. METHODS: In vitro Raman spectra from children with aEoE (n = 8; spectra = 51) and iEoE (n = 6; spectra = 48) and from non-EoE controls (n = 10; spectra = 75) were acquired. Mann-Whitney test was used to assess the differences in their Raman intensities (median [interquartile range]) and identify spectral markers. Spearman correlation was used to evaluate the relationship between spectral markers and endoscopic and histologic activity indices. RESULTS: Raman peaks attributable to glycogen content (936/1,449 cm) was lower in children with aEoE (0.20 [0.18-0.21]) compared with that in non-EoE controls (0.24 [0.23-0.29]). Raman intensity of proteins (1,660/1,209 cm) was higher in children with aEoE compared with that in non-EoE controls (3.20 [3.07-3.50] vs 2.91 [2.59-3.05]; P = 0.01), whereas that of lipids (1,301/1,260 cm) was higher in children with iEoE (1.56 [1.49-1.63]) compared with children with aEoE (1.40 [1.30-1.48]; P = 0.02). Raman peaks attributable to glycogen and lipid inversely correlated with eosinophilic inflammation and basal zone hyperplasia. Raman mapping substantiated our findings. DISCUSSION: This is the first study to identify spectral traits of the esophageal samples related to EoE activity and tissue pathology and to profile tissue-level biochemical composition associated with pediatric EoE. Future research to determine the role of these biochemical alterations in development and clinical course of EoE can advance our understanding of EoE pathobiology.

Correlation of endoscopic signs and mucosal alterations in children with eosinophilic esophagitis.

BACKGROUND AND AIMS: In children with eosinophilic esophagitis (EoE), the relationship among the endoscopic reference score (EREFS), the histology scoring system (EoEHSS), and the peak eosinophil count (PEC) is incompletely described. Our aim was to determine the relationship among EREFS, EoEHSS, and PEC and develop a predictive model using components of EREFS and EoEHSS for EoE activity. METHODS: We analyzed 189 paired EREFSs, EoEHSSs, and PECs. Active EoE (aEoE; n = 98) was defined as ≥15 eosinophils per high-power field and inactive EoE (iEoE; n = 91) as <15 eosinophils per high-power field. Spearman correlation (r) with Bonferroni correction was used to assess the relationship between EREFS, EoEHSS and PEC, and a back-transformed average Fisher test was used to determine the statistical significance of the differences. Receiver operating characteristic analysis was used to develop the predictive model. RESULTS: The relationship between total EREFS and EoEHSS was modest (r = 0.61) but significantly stronger than the correlation between total EREFS and PEC (r = 0.55; P = .04). The relationship between total EREFS and EoEHSS tended to be stronger in aEoE compared with iEoE (r = 0.41 vs 0.24; P = .09). Compared with EREFS, EoEHSS had a significantly higher area under the curve (0.78 vs 0.92; P = .04) to predict aEoE. A combination of furrows, eosinophilic inflammation, basal cell hyperplasia, eosinophilic abscess, and dilated intercellular spaces had an area under the curve of 0.97, accuracy of 98%, sensitivity of 97%, and specificity of 98% to predict aEoE. CONCLUSIONS: The endoscopy score modestly correlates with the histologic scoring system. Thus, the endoscopy score is not a reliable marker of tissue involvement in EoE. A panel of individual endoscopic and histologic signs hold promise to accurately predict EoE activity.

The Salivary Microbiome Is Altered in Children With Eosinophilic Esophagitis and Correlates With Disease Activity.

OBJECTIVES: Eosinophilic esophagitis (EoE) is an allergen-mediated inflammatory disease affecting the esophagus. Although microbial communities may affect the host immune responses, little is known about the role of the microbiome in EoE. We compared the composition of the salivary microbiome in children with EoE with that of non-EoE controls to test the hypotheses that the salivary microbiome is altered in children with EoE and is associated with disease activity. METHODS: Saliva samples were collected from 26 children with EoE and 19 non-EoE controls comparable for age and ethnicity. The salivary microbiome was profiled using 16S rRNA gene sequencing. Disease activity was assessed using the Eosinophilic Esophagitis Endoscopic Reference Score and the Eosinophilic Esophagitis Histologic Scoring System (EoEHSS). RESULTS: A trend toward lower microbial richness and alpha diversity was noted in children with EoE. Although the overall salivary microbiome composition was similar between children with and without EoE, specific taxa such as Streptococcus (q value = 0.06) tended to be abundant in children with active EoE compared with non-EoE controls. Haemophilus was significantly abundant in children with active EoE compared with inactive EoE (q value = 0.0008) and increased with the increasing EoEHSS and Eosinophilic Esophagitis Histology Scoring System (q value = 5e-10). In addition, 4 broad salivary microbial communities correlated with the EoEHSS. DISCUSSION: The composition of the salivary microbiome community structure can be altered in children with EoE. A relative abundance of Haemophilus positively correlates with the disease activity. These findings indicate that perturbations in the salivary microbiome may have a role in EoE pathobiology and could serve as a noninvasive marker of disease activity.

Production of a Functional Factor, p40, by Lactobacillus rhamnosus GG Is Promoted by Intestinal Epithelial Cell-Secreted Extracellular Vesicles.

The symbiotic relationship between the gut microbiome and the host provides a nutrient-rich environment for gut microbes and has beneficial effects on host health. Although the composition of the gut microbiome is known to be influenced by both host genetics and environmental factors, host effects on the activities and functions of the gut microbial communities remain poorly understood. Intestinal epithelial cells exert front-line responses to gut microbes and contribute to maintaining a healthy intestinal homeostasis. Here, seeking to elucidate whether intestinal epithelial cells modulate Lactobacillus rhamnosus GG (LGG) functions, we examined the production of p40, an LGG-derived secretory protein that protects intestinal epithelial cells against inflammation. We found that growth medium conditioned with colonic epithelial cell-derived components promotes p40 protein synthesis and secretion by LGG and enhances LGG-stimulated protective responses in intestinal epithelial cells. Furthermore, when LGG was cultured with the colonic luminal contents from healthy mice, p40 production was upregulated but was attenuated with luminal contents from mice with intestinal inflammation. Importantly, the colonic epithelial cell-derived components potentiated LGG-produced p40 levels in a mouse model of colitis and enhanced LGG-mediated amelioration of intestinal inflammation in this model. Notably, we found that colonic epithelial cell-secreted extracellular vesicles participate in communicating with LGG and that heat shock protein 90 (HSP90) in these vesicles might mediate the promotion of p40 production. These results reveal a previously unrecognized mechanism by which the anti-inflammatory effect of LGG is reinforced by intestinal epithelial cells and thereby maintains intestinal health.

Autoimmune Enteropathy: An Updated Review with Special Focus on Stem Cell Transplant Therapy.

Autoimmune enteropathy (AIE) is a complex disease affecting both children and adults. Although associated with significant morbidity and mortality, the pathophysiology of the disease and its treatment have not been well characterized. This study aims to review the medical literature available on this rare but clinically significant ailment, to help establish a better understanding of its pathophysiology and enumerate the available diagnostic and treatment modalities. A literature search was conducted on PubMed using key terms related to autoimmune enteropathy and intractable diarrhea, with no restrictions on the date of publication or language. We found a total of 98 reports of AIE published in the form of case reports and case series. The evidence reviewed suggests that AIE is a multifaceted disorder that requires a high index of suspicion in the appropriate clinical setting to be able to make an early diagnosis. Current evidence supports the use of supportive care to correct nutritional and metabolic deficiencies, and immunosuppressives and immunomodulators as directed therapies. Hematopoietic stem cell transplant is an aggressive, but successful curative modality for patients with AIE as part of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. Cumulative clinical experience with management of AIE has allowed improved outcomes in transplanted and non-transplanted AIE patients even though morbidity and mortality with are still high in patients with this condition. More research is needed to further define the role of new therapies for AIE, and a central registry with participation of multiple institutions might help share and standardize care of patients with this rare but serious condition.

Fecal transplantation for treatment of inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic, relapsing disease of the gastrointestinal tract that is thought to be associated with a complex interplay between microbes and the immune system, leading to an abnormal inflammatory response in genetically susceptible individuals. Dysbiosis, characterized by the alteration of the composition of the resident commensal bacteria in a host compared to healthy individuals, is thought to play a major role in the pathogenesis of ulcerative colitis (UC) and Crohn's disease (CD), two subtypes of IBD. There is growing interest to correct the underlying dysbiosis through the use of fecal microbiota transplantation (FMT) for the treatment of IBD. OBJECTIVES: The objective of this systematic review was to assess the efficacy and safety of FMT for the treatment of IBD. SEARCH METHODS: We searched the MEDLINE, Embase, Cochrane Library, and Cochrane IBD Group Specialized Register databases from inception to 19 March 2018. We also searched ClinicalTrials.gov, ISRCTN metaRegister of Controlled Trials, and the Conference Proceedings Citation Index. SELECTION CRITERIA: Only randomized trials or non-randomized studies with a control arm were considered for inclusion. Adults or pediatric participants with UC or CD were eligible for inclusion. Eligible interventions were FMT defined as the administration of fecal material containing distal gut microbiota from a healthy donor to the gastrointestinal tract of a someone with UC or CD. The comparison group included participants who did not receive FMT and were given placebo, autologous FMT, or no intervention. DATA COLLECTION AND ANALYSIS: Two authors independently screened the titles and extracted data from the included studies. We used the Cochrane risk of bias tool to assess study bias. The primary outcomes were induction of clinical remission, clinical relapse, and serious adverse events. Secondary outcomes included clinical response, endoscopic remission and endoscopic response, quality of life scores, laboratory measures of inflammation, withdrawals, and microbiome outcomes. We calculated the risk ratio (RR) and corresponding 95% confidence interval (95% CI) for dichotomous outcomes and the mean difference and 95% CI for continuous outcomes. Random-effects meta-analysis models were used to synthesize effect sizes across trials. The overall certainty of the evidence supporting the primary and selected secondary outcomes was rated using the GRADE criteria. MAIN RESULTS: Four studies with a total of 277 participants were included. These studies assessed the efficacy of FMT for treatment of UC in adults; no eligible trials were found for the treatment of CD. Most participants had mild to moderate UC. Two studies were conducted in Australia, one study was conducted in Canada, and another in the Netherlands. Three of the included studies administered FMT via the rectal route and one study administered FMT via the nasoduodenal route. Three studies were rated as low risk of bias. One study (abstract publication) was rated as unclear risk of bias. Combined results from four studies (277 participants) suggest that FMT increases rates of clinical remission by two-fold in patients with UC compared to controls. At 8 weeks, 37% (52/140) of FMT participants achieved remission compared to 18% (24/137) of control participants (RR 2.03, 95 % CI, 1.07 to 3.86; I² = 50%; low certainty evidence). One study reported data on relapse at 12 weeks among participants who achieved remission. None of the FMT participants (0/7) relapsed at 12 weeks compared to 20% of control participants (RR 0.28, 95% CI 0.02 to 4.98, 17 participants, very low certainty evidence). It is unclear whether there is a difference in serious adverse event rates between the intervention and control groups. Seven per cent (10/140) of FMT participants had a serious adverse event compared to 5% (7/137) of control participants (RR 1.40, 95% CI 0.55 to 3.58; 4 studies; I² = 0%; low certainty evidence). Serious adverse events included worsening of UC necessitating intravenous steroids or surgery; infection such as Clostridium difficile and cytomegalovirus, small bowel perforation and pneumonia. Adverse events were reported by two studies and the pooled data did not show any difference between the study groups. Seventy-eight per cent (50/64) of FMT participants had an adverse event compared to 75% (49/65) of control participants (RR 1.03, 95% CI 0.81 to 1.31; I² = 31%; moderate certainty evidence). Common adverse events included abdominal pain, nausea, flatulence, bloating, upper respiratory tract infection, headaches, dizziness, and fever. Four studies reported on clinical response at 8 weeks. Forty-nine per cent (68/140) of FMT participants had a clinical response compared to 28% (38/137) of control participants (RR 1.70, 95% CI 0.98 to 2.95, I² = 50%, low certainty evidence). Endoscopic remission at 8 weeks was reported by three studies and the combined results favored FMT over the control group. Thirty per cent (35/117) of FMT participants achieved endoscopic remission compared to 10% (11/112) of control participants (RR 2.96, 95 % CI 1.60 to 5.48, I² = 0%; low certainty evidence). AUTHORS' CONCLUSIONS: Fecal microbiota transplantation may increase the proportion of participants achieving clinical remission in UC. However, the number of identified studies was small and the quality of evidence was low. There is uncertainty about the rate of serious adverse events. As a result, no solid conclusions can be drawn at this time. Additional high-quality studies are needed to further define the optimal parameters of FMT in terms of route, frequency, volume, preparation, type of donor and the type and disease severity. No studies assessed efficacy of FMT for induction of remission in CD or in pediatric participants. In addition, no studies assessed long-term maintenance of remission in UC or CD. Future studies are needed to address the therapeutic benefit of FMT in CD and the long-term FMT-mediated maintenance of remission in UC or CD.

Supplementation of p40, a Lactobacillus rhamnosus GG-derived protein, in early life promotes epidermal growth factor receptor-dependent intestinal development and long-term health outcomes.

The beneficial effects of the gut microbiota on growth in early life are well known. However, knowledge about the mechanisms underlying regulating intestinal development by the microbiota is limited. p40, a Lactobacillus rhamnosus GG-derived protein, transactivates epidermal growth factor receptor (EGFR) in intestinal epithelial cells for protecting the intestinal epithelium against injury and inflammation. Here, we developed p40-containing pectin/zein hydrogels for targeted delivery of p40 to the small intestine and the colon. Treatment with p40-containing hydrogels from postnatal day 2 to 21 significantly enhanced bodyweight gain prior to weaning and functional maturation of the intestine, including intestinal epithelial cell proliferation, differentiation, and tight junction formation, and IgA production in early life in wild-type mice. These p40-induced effects were abolished in mice with specific deletion of EGFR in intestinal epithelial cells, suggesting that transactivation of EGFR in intestinal epithelial cells may mediate p40-regulated intestinal development. Furthermore, neonatal p40 treatment reduced the susceptibility to intestinal injury and colitis and promoted protective immune responses, including IgA production and differentiation of regulatory T cells, in adult mice. These findings reveal novel roles of neonatal supplementation of probiotic-derived factors in promoting EGFR-mediated maturation of intestinal functions and innate immunity, which likely promote long-term beneficial outcomes.

Advances in Evaluation of Chronic Diarrhea in Infants.

Diarrhea is common in infants (children less than 2 years of age), usually acute, and, if chronic, commonly caused by allergies and occasionally by infectious agents. Congenital diarrheas and enteropathies (CODEs) are rare causes of devastating chronic diarrhea in infants. Evaluation of CODEs is a lengthy process and infrequently leads to a clear diagnosis. However, genomic analyses and the development of model systems have increased our understanding of CODE pathogenesis. With these advances, a new diagnostic approach is needed. We propose a revised approach to determine causes of diarrhea in infants, including CODEs, based on stool analysis, histologic features, responses to dietary modifications, and genetic tests. After exclusion of common causes of diarrhea in infants, the evaluation proceeds through analyses of stool characteristics (watery, fatty, or bloody) and histologic features, such as the villus to crypt ratio in intestinal biopsies. Infants with CODEs resulting from defects in digestion, absorption, transport of nutrients and electrolytes, or enteroendocrine cell development or function have normal villi to crypt ratios; defects in enterocyte structure or immune-mediated conditions result in an abnormal villus to crypt ratios and morphology. Whole-exome and genome sequencing in the early stages of evaluation can reduce the time required for a definitive diagnosis of CODEs, or lead to identification of new variants associated with these enteropathies. The functional effects of gene mutations can be analyzed in model systems such as enteroids or induced pluripotent stem cells and are facilitated by recent advances in gene editing procedures. Characterization and investigation of new CODE disorders will improve management of patients and advance our understanding of epithelial cells and other cells in the intestinal mucosa.

Mucosal Impedance Measurements Differentiate Pediatric Patients With Active Versus Inactive Eosinophilic Esophagitis.

BACKGROUND AND AIMS: Eosinophilic esophagitis (EoE) is a chronic disorder in children that requires continued assessment of disease activity, involving repeated sedation, endoscopy, and biopsy analysis. We investigated whether mucosal impedance measurements can be used to monitor disease activity in pediatric patients with EoE. METHODS: We measured mucosal impedance at 3 locations in the esophagus in pediatric patients (1-18 years old; 32 with active EoE, 10 with inactive EoE, 32 with nonerosive reflux disease [NERD]) and 53 children with symptoms but normal findings from histologic analyses (controls) undergoing routine esophagogastroduodenoscopy at the Vanderbilt Pediatric Gastroenterology Clinic. Pathologists reviewed biopsies per routine protocol, determined eosinophilic density, and graded spongiosis on an ordinal visual scale. Mucosal impedance measurements were compared within patient groups. The primary outcome was correlation of mucosal impedance measurements with disease activity, based on severity of spongiosis and eosinophil counts. RESULTS: Mucosal impedance measurements were significantly lower in patients with active EoE at 2, 5, and 10 cm above the squamo-columnar junction (median values of 1069, 1368, and 1707, respectively) compared to patients with inactive EoE (median values of 3663, 3657, and 4494, respectively), NERD (median values of 2754, 3243, and 4387), and controls (median values of 3091, 3760, and 4509) (P < 0.001 for all comparisons to patients with active EoE). We found inverse correlations between mucosal impedance measurements and eosinophil count (P < 0.001), and spongiosis severity (P < 0.001). CONCLUSIONS: Mucosal impedance measurements may provide immediate information about mucosal inflammation in children. Patients with active EoE have significantly lower mucosal impedance values than patients with inactive EoE, NERD, or controls; mucosal impedance measurements correlate inversely with eosinophil counts and spongiosis severity. Mucosal impedance is a promising rapid and less-invasive method to monitor EoE activity in pediatric patients with EoE; it could reduce costs and risks of disease monitoring.

Management of Esophageal Food Impaction Varies Among Gastroenterologists and Affects Identification of Eosinophilic Esophagitis.

BACKGROUND AND AIMS: Esophageal food impaction (EFI) is a gastrointestinal emergency requiring immediate evaluation in the emergency room (ER) and an esophagogastroduodenoscopy (EGD) for disimpaction. EFI is also a distinct presenting feature of eosinophilic esophagitis (EoE). This study aimed at understanding the management of EFI among gastroenterologists (GIs) and estimated its impact on identification of EoE in USA. METHODS: GIs associated with three major gastroenterology societies based in USA were invited to participate in a web-based survey. Information on the resources available and utilized, and the clinical decision-making process related to management of EFI cases was collected and analyzed. RESULTS: Of 428 responses, 49% were from pediatric GIs, 86% practiced in the USA, and 78% practiced in an academic setting. Compared to the pediatric GIs, adult GIs were more likely to perform EGD in the emergency room [OR 87.96 (25.43-304.16)] and advance the food bolus into stomach [5.58 (3.08-10.12)]. Only 34% of respondents obtained esophageal biopsies during EGD, and pediatric GIs were more likely to obtain esophageal biopsies [3.49 (1.12-10.84)] compared to adult GIs. In USA, by our conservative estimates, 10,494 patients presenting to ER with EFI and at risk of EoE are likely being missed each year. CONCLUSIONS: EFI management varies substantially among GIs associated with three major gastroenterology societies in USA. Based on their practice patterns, the GIs in USA are likely to miss numerous EoE patients presenting to ER with EFI. Our findings highlight the need for developing and disseminating evidence-based EFI management practice guidelines.

Clostridium difficile infection in the pediatric transplant patient.

CDIs are on the rise in both hospital and community settings in adults and children. Children with cancer or a history of HSCT or SOT appear to be at higher risk for primary disease, recurrent disease, and severe outcomes when compared to children with other comorbidities. The reasons for this are not clear and no studies to date have analyzed risk factors for CDI in pediatric transplant patients. Colonization rates in children with cancer and a transplant history are also high. Determining which children are colonized with Clostridium difficile and symptomatic from another source vs. symptomatic from CDI is difficult and a clinical conundrum for the transplant physician. The use of fecal transplantation for severe or rCDI is likely safe and effective in the immunosuppressed pediatric cancer or transplant patient, but this will need to be more thoroughly studied in this patient population.

Eosinophilic Laryngitis in Children with Aerodigestive Dysfunction.

OBJECTIVE: To describe the presence of laryngeal eosinophils and associated symptomatology in patients with aerodigestive dysfunction. STUDY DESIGN: Case series with chart review. SETTING: Single tertiary pediatric referral center. SUBJECTS: Eighty-one consecutive pediatric patients referred to a multidisciplinary aerodigestive clinic with upper airway concerns. METHODS: Microlaryngoscopy and posterior arytenoid biopsy, flexible bronchoscopy, esophagogastroduodenoscopy and esophageal biopsy, and impedance probe testing were performed as indicated by clinical symptoms. Positive versus negative posterior arytenoid biopsy for eosinophils and the presence or absence of concomitant histopathological laryngitis and/or esophagitis were measured. RESULTS: Nine of 81 (11%) patients had positive laryngeal biopsy for eosinophils (range, 1-29 eosinophils/high-powered field [HPF]). Three of these 9 patients also had concurrent biopsy-proven eosinophilic esophagitis, while 8 of 81 total patients had biopsy-proven eosinophilic esophagitis. The frequency of biopsy-proven eosinophilic esophagitis was higher in patients with posterior arytenoid eosinophils versus patients without laryngeal eosinophils (33% versus 6.9%, P = .0408). CONCLUSIONS: Eosinophilic inflammation in the larynx has not been described in children with complex aerodigestive complaints. Posterior arytenoid eosinophils may serve as a marker of chronic laryngeal inflammation in children with aerodigestive dysfunction, although their exact role in this inflammation remains unclear. In our population, >15 eosinophils/HPF within posterior arytenoid biopsies was associated with concomitant eosinophilic esophagitis.