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BACKGROUNDThe use of high-throughput technologies has enabled rapid advancement in the knowledge of host immune responses to pathogens. Our objective was to compare the repertoire, protection, and maternal factors associated with human milk antibodies to infectious pathogens in different economic and geographic locations.METHODSUsing multipathogen protein microarrays, 878 milk and 94 paired serum samples collected from 695 women in 5 high and low-to-middle income countries (Bangladesh, Finland, Peru, Pakistan, and the United States) were assessed for specific IgA and IgG antibodies to 1,607 proteins from 30 enteric, respiratory, and bloodborne pathogens.RESULTSThe antibody coverage across enteric and respiratory pathogens was highest in Bangladeshi and Pakistani cohorts and lowest in the U.S. and Finland. While some pathogens induced a dominant IgA response (Campylobacter, Klebsiella, Acinetobacter, Cryptosporidium, and pertussis), others elicited both IgA and IgG antibodies in milk and serum, possibly related to the invasiveness of the infection (Shigella, enteropathogenic E. coli "EPEC", Streptococcus pneumoniae, Staphylococcus aureus, and Group B Streptococcus). Besides the differences between economic regions and decreases in concentrations over time, human milk IgA and IgG antibody concentrations were lower in mothers with high BMI and higher parity, respectively. In Bangladeshi infants, a higher specific IgA concentration in human milk was associated with delayed time to rotavirus infection, implying protective properties of antirotavirus antibodies, whereas a higher IgA antibody concentration was associated with greater incidence of Campylobacter infection.CONCLUSIONThis comprehensive assessment of human milk antibody profiles may be used to guide the development of passive protection strategies against infant morbidity and mortality.FUNDINGBill and Melinda Gates Foundation grant OPP1172222 (to KMJ); Bill and Melinda Gates Foundation grant OPP1066764 funded the MDIG trial (to DER); University of Rochester CTSI and Environmental Health Sciences Center funded the Rochester Lifestyle study (to RJL); and R01 AI043596 funded PROVIDE (to WAP).
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Immunoglobuline A , Immunoglobuline G , Lait humain , Humains , Lait humain/immunologie , Femelle , Immunoglobuline A/sang , Immunoglobuline A/immunologie , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Adulte , Anticorps antibactériens/sang , Anticorps antibactériens/immunologie , Bangladesh/épidémiologieRÉSUMÉ
OBJECTIVE: To describe the intrapartum and postpartum use of non-study antibiotics in low- and middle-income countries (LMICs) during the double-blinded NICHD Global Network Azithromycin in Labor (A-PLUS) trial. DESIGN: The antibiotic use sub-study was a planned prospective, observational sub-study of the A-PLUS trial. SETTINGS: The study was carried out in hospitals or health centres affiliated with eight sites of the Global Network for Women's and Children's Health Research (Global Network) in seven countries: Bangladesh, Pakistan, India (two sites), Kenya, Zambia, The Democratic Republic of the Congo (DRC) and Guatemala. POPULATION: Totally, 29 278 pregnant women enrolled in the A-PLUS trial. METHODS: We collected data on 29 278 pregnant women admitted to a facility for delivery related to non-study antibiotic use overall and during three time periods: (1) in the facility prior to delivery, (2) after delivery until facility discharge and (3) after discharge to 42 days post-partum. MAIN OUTCOME MEASURES: Non-study antibiotic use overall and for treatment or prophylaxis by the site during the three time periods. RESULTS: Of the 29 278 women in the study, 5020 (17.1%; 95% CI 16.7%-17.6%) received non-study antibiotics in the facility prior to delivery, 11 956 (40.8%; 95% CI 40.3%-41.4%) received non-study antibiotics in the facility after delivery, and 13 390 (47.6%; 95% CI 47.0%-48.2%) women received non-study antibiotics after delivery and after facility discharge. Antibiotics were prescribed more often among women in the Asian and Guatemalan sites than in the African sites. In the three time-periods, among those receiving antibiotics, prophylaxis was the indication in 82.3%, 97.7% and 90.7% of the cases, respectively. The type of antibiotics used varied substantially by time-period and site, but generally, penicillin-type drugs, cephalosporin-type drugs and metronidazole were used more frequently than other types. CONCLUSIONS: Across the eight sites of the Global Network, in the facility before delivery, and in the post-partum periods before and after facility discharge, antibiotics were used frequently, but use was highly variable by site and time-period.
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Entamoeba histolytica, the causative agent of amebiasis, is one of the top three parasitic causes of mortality worldwide. However, no vaccine exists against amebiasis. Using a lead candidate vaccine containing the LecA fragment of Gal-lectin and GLA-3M-052 liposome adjuvant, we immunized rhesus macaques via intranasal or intramuscular routes. The vaccine elicited high-avidity functional humoral responses as seen by the inhibition of amebic attachment to mammalian target cells by plasma and stool antibodies. Importantly, antigen-specific IFN-γ-secreting peripheral blood mononuclear cells (PBMCs) and IgG/IgA memory B cells (BMEM) were detected in immunized animals. Furthermore, antigen-specific antibody and cellular responses were maintained for at least 8 months after the final immunization as observed by robust LecA-specific BMEM as well as IFN-γ+ PBMC responses. Overall, both intranasal and intramuscular immunizations elicited a durable and functional response in systemic and mucosal compartments, which supports advancing the LecA+GLA-3M-052 liposome vaccine candidate to clinical testing.
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Administration par voie nasale , Anticorps antiprotozoaires , Entamoeba histolytica , Infection à Entamoeba , Interféron gamma , Agranulocytes , Liposomes , Macaca mulatta , Vaccins antiprotozoaires , Animaux , Entamoeba histolytica/immunologie , Liposomes/immunologie , Liposomes/administration et posologie , Vaccins antiprotozoaires/immunologie , Vaccins antiprotozoaires/administration et posologie , Anticorps antiprotozoaires/sang , Anticorps antiprotozoaires/immunologie , Agranulocytes/immunologie , Infection à Entamoeba/prévention et contrôle , Infection à Entamoeba/immunologie , Interféron gamma/immunologie , Interféron gamma/métabolisme , Injections musculaires , Immunogénicité des vaccins , Adjuvants vaccinaux/administration et posologie , Adjuvants immunologiques/administration et posologie , Lymphocytes B/immunologie , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Immunoglobuline A/immunologie , Immunoglobuline A/sang , Antigènes de protozoaire/immunologie , Immunité humorale , Mémoire immunologique , Protéines de protozoaire/immunologieRÉSUMÉ
To evaluate how breakthrough rotavirus disease contributes to transmission, we examined the impact of rotavirus vaccination on fecal shedding and duration of illness. We used multivariable linear regression to analyze rotavirus quantity by RT-qPCR and duration among 184 episodes of rotavirus diarrhea positive by ELISA in the PROVIDE study. Vaccinated children had less fecal viral shedding compared to unvaccinated children (mean difference = -0.59 log copies per gram of stool; 95% confidence interval [CI], -.99 to -.19). Duration of illness was on average 0.47 days (95% CI, -.23 to 1.17 days) shorter among vaccinated children. Rotarix vaccination reduces shedding burden among breakthrough cases of rotavirus gastroenteritis. Clinical Trials Registration . NCT01375647.
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Fèces , Infections à rotavirus , Vaccins anti-rotavirus , Rotavirus , Vaccins atténués , Excrétion virale , Humains , Vaccins anti-rotavirus/administration et posologie , Vaccins anti-rotavirus/immunologie , Infections à rotavirus/prévention et contrôle , Infections à rotavirus/épidémiologie , Infections à rotavirus/virologie , Nourrisson , Bangladesh/épidémiologie , Rotavirus/immunologie , Fèces/virologie , Femelle , Mâle , Vaccins atténués/administration et posologie , Vaccins atténués/immunologie , Gastroentérite/virologie , Gastroentérite/prévention et contrôle , Gastroentérite/épidémiologie , Vaccination , Diarrhée/virologie , Diarrhée/prévention et contrôle , Diarrhée/épidémiologie , Administration par voie oraleRÉSUMÉ
BACKGROUND: Clostridioides difficile infection results in life-threatening short-term outcomes and the potential for subsequent recurrent infection. Predicting these outcomes at diagnosis, when important clinical decisions need to be made, has proven to be a difficult task. METHODS: 52 clinical features from existing models or the literature were collected retrospectively within ±48 h of diagnosis among 1660 inpatient infections. A modified desirability of outcome ranking (DOOR) was designed to encompass clinically-important severe events attributable to the acute infection (intensive care transfer due to sepsis, shock, colectomy/ileostomy, mortality) and/or 60-day recurrence. A deep neural network was constructed and interpreted using SHapley Additive exPlanations (SHAP). High-importance features were used to train a reduced, shallow network and performance was compared to existing conventional models (7 severity, 7 recurrence; after summing DOOR probabilities to align with conventional binary outputs) using area under the ROC curve (AUROC) and DeLong tests. FINDINGS: The full (52-feature) model achieved an out-of-sample AUROC 0.823 for severity and 0.678 for recurrence. SHAP identified 13 unique, highly-important features (age, hypotension, initial treatment, onset, PCR cycle threshold, number of prior episodes, antibiotic exposure, fever, hypotension, pressors, leukocytosis, creatinine, lactate) that were used to train a reduced model, which performed similarly to the full model (severity AUROC difference P = 0.130; recurrence P = 0.426) and significantly better than the top severity model (reduced model predicting severity 0.837, ATLAS 0.749; P = 0.001). The reduced model also outperformed the top recurrence model, but this was not statistically-significant (reduced model recurrence AUROC 0.653, IDSA Recurrence Risk Criteria 0.595; P = 0.196). The final, reduced model was deployed as a web application with real-time SHAP explanations. INTERPRETATION: Our final model outperformed existing severity and recurrence models; however, it requires external validation. A DOOR output allows specific clinical questions to be asked with explainable predictions that can be feasibly implemented with limited computing resources. FUNDING: National Institutes of Health-Institute of Allergy and Infectious Diseases.
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Clostridioides difficile , Infections à Clostridium , Apprentissage machine , Humains , Infections à Clostridium/diagnostic , Infections à Clostridium/microbiologie , Mâle , Femelle , Courbe ROC , Sujet âgé , Adulte d'âge moyen , Pronostic , Récidive , Études rétrospectives , Aire sous la courbeRÉSUMÉ
Crohn's disease is an inflammatory condition of the intestine characterized by largely unknown etiology and a relapse remission cycle of disease control. While possible triggers have been identified, research is inconsistent on the precise cause of these relapses, especially in the under-researched pediatric population. We hypothesized that patients in remission would have persistent microbial and inflammatory changes in small intestinal tissue that might trigger relapse. To this end, we analyzed intestinal biopsy samples from six patients with pediatric Crohn's disease in remission and a control group of 16 pediatric patients with no evident pathogenic abnormality. We identified compositional microbiota differences, including decreases in the genera Streptococcus and Actinobacillus as well as increases in Oribacterium and Prevotella in patients with controlled Crohn's disease compared to controls. Further, a histologic analysis found that patients with controlled Crohn's disease had increased epithelial integrity, and decreased intraepithelial lymphocytes compared with controls. Additionally, we observed increased peripheral CD4+ T cells in patients with pediatric Crohn's disease. These results indicate that markers of intestinal inflammation are responsive to Crohn's disease treatment, however the interventions may not resolve the underlying dysbiosis. These findings suggest that persistent dysbiosis may increase vulnerability to relapse of pediatric Crohn's disease. This study used a nested cohort of patients from the Bangladesh Environmental Enteric Dysfunction (BEED) study (ClinicalTrials.gov ID: NCT02812615 Date of first registration: 24/06/2016).
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Maladie de Crohn , Dysbiose , Microbiome gastro-intestinal , Humains , Maladie de Crohn/microbiologie , Maladie de Crohn/anatomopathologie , Maladie de Crohn/complications , Dysbiose/microbiologie , Femelle , Mâle , Enfant , Adolescent , Duodénum/microbiologie , Duodénum/anatomopathologie , Inflammation/microbiologie , Inflammation/anatomopathologie , Études cas-témoinsRÉSUMÉ
Malnutrition in children, defined as a child who is more than 2 standard deviations below the norm for height- or weight-for-age, is a pervasive, population-wide problem in low- and middle-income countries. Malnutrition is associated with increased infant mortality and delayed neurocognitive development. A recent pooled analysis of more than 30 longitudinal cohort studies demonstrated that the conditions mothers lived in during pregnancy, and their access to adequate nutrition, was a major factor in the subsequent growth and health of their children. We review here this analysis and the hypothesis that interventions to address childhood malnutrition need to start before birth and continue throughout the critical first 1,000 days of life.
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Malnutrition , Humains , Femelle , Nourrisson , Grossesse , Troubles nutritionnels de l'enfant , Enfant d'âge préscolaire , Enfant , Nouveau-né , Mères , État nutritionnelRÉSUMÉ
OBJECTIVE: We sought to validate available tools for predicting recurrent C. difficile infection (CDI) including recurrence risk scores (by Larrainzar-Coghen, Reveles, D'Agostino, Cobo, and Eyre et al) alongside consensus guidelines risk criteria, the leading severity score (ATLAS), and PCR cycle threshold (as marker of fecal organism burden) using electronic medical records. DESIGN: Retrospective cohort study validating previously described tools. SETTING: Tertiary care academic hospital. PATIENTS: Hospitalized adult patients with CDI at University of Virginia Medical Center. METHODS: Risk scores were calculated within ±48 hours of index CDI diagnosis using a large retrospective cohort of 1,519 inpatient infections spanning 7 years and compared using area under the receiver operating characteristic curve (AUROC) and the DeLong test. Recurrent CDI events (defined as a repeat positive test or symptom relapse within 60 days requiring retreatment) were confirmed by clinician chart review. RESULTS: Reveles et al tool achieved the highest AUROC of 0.523 (and 0.537 among a subcohort of 1,230 patients with their first occurrence of CDI), which was not substantially better than other tools including the current IDSA/SHEA C. difficile guidelines or PCR cycle threshold (AUROC: 0.564), regardless of prior infection history. CONCLUSIONS: All tools performed poorly for predicting recurrent C. difficile infection (AUROC range: 0.488-0.564), especially among patients with a prior history of infection (AUROC range: 0.436-0.591). Future studies may benefit from considering novel biomarkers and/or higher-dimensional models that could augment or replace existing tools that underperform.
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Background: Astroviral infections commonly cause acute nonbacterial gastroenteritis in children globally. However, these infections often go undiagnosed outside of research settings. There is no treatment available for astrovirus, and Astroviridae strain diversity presents a challenge to potential vaccine development. Methods: To address our hypothesis that host genetic risk factors are associated with astrovirus disease susceptibility, we performed a genome-wide association study of astrovirus infection in the first year of life from children enrolled in 2 Bangladeshi birth cohorts. Results: We identified a novel region on chromosome 1 near the loricrin gene (LOR) associated with astrovirus diarrheal infection (rs75437404; meta-analysis P = 8.82 × 10-9; A allele odds ratio, 2.71) and on chromosome 10 near the prolactin releasing hormone receptor gene (PRLHR) (rs75935441; meta-analysis P = 1.33 × 10-8; C allele odds ratio, 4.17). The prolactin-releasing peptide has been shown to influence feeding patterns and energy balance in mice. In addition, several single-nucleotide polymorphisms in the chromosome 1 locus have previously been associated with expression of innate immune system genes PGLYRP4, S100A9, and S100A12. Conclusions: This study identified 2 significant host genetic regions that may influence astrovirus diarrhea susceptibility and should be considered in further studies.
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The infant non-secretor histoblood group antigen phenotype is associated with reduced risk of symptomatic rotavirus diarrhea, one of the leading global causes of severe pediatric diarrheal disease and mortality. However, little is known regarding the role of secretor status in asymptomatic rotavirus infections. Therefore, we performed a nested case-control study within a birth cohort study previously conducted in Dhaka, Bangladesh, to determine the association between infant secretor phenotype and the odds of asymptomatic rotavirus infection, in addition to the risk of rotavirus diarrhea, in unvaccinated infants. In the parent cohort, infants were enrolled in the first week of life and followed through the first two years of life with multiple clinic visits and active surveillance for diarrheal illness. Secretor phenotyping was performed on saliva. Eleven surveillance stools collected over the first year of life were tested for rotavirus by real-time RT-PCR, followed by conventional PCR and amplicon sequencing to identify the infecting P-type of positive specimens. Similar to findings for symptomatic diarrhea, infant non-secretors experienced significantly fewer primary episodes of asymptomatic rotavirus infection through the first year of life in a likely rotavirus P-genotype-dependent manner. These data suggest that non-secretors experienced reduced risk from rotavirus due to decreased susceptibility to infection rather than reduced infection severity.
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Small intestine bacterial overgrowth (SIBO) has been associated with enteric inflammation, linear growth stunting, and neurodevelopmental delays in children from low-income countries. Little is known about the histologic changes or epithelial adherent microbiota associated with SIBO. We sought to describe these relationships in a cohort of impoverished Bangladeshi children. Undernourished 12-18-month-old children underwent both glucose hydrogen breath testing for SIBO and duodenoscopy with biopsy. Biopsy samples were subject to both histological scoring and 16s rRNA sequencing. 118 children were enrolled with 16s sequencing data available on 53. Of 11 histological features, we found that SIBO was associated with one, enterocyte injury in the second part of the duodenum (R = 0.21, p = 0.02). SIBO was also associated with a significant increase in Campylobacter by 16s rRNA analysis (Log 2-fold change of 4.43; adjusted p = 1.9 x 10-6). These findings support the growing body of literature showing an association between SIBO and enteric inflammation and enterocyte injury and further delineate the subgroup of children with environmental enteric dysfunction who have SIBO. Further, they show a novel association between SIBO and Campylobacter. Mechanistic work is needed to understand the relationship between SIBO, enterocyte injury, and Campylobacter.
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Infections bactériennes , Intestin grêle , Enfant , Humains , Nourrisson , ARN ribosomique 16S/génétique , Intestin grêle/microbiologie , Duodénum/microbiologie , Infections bactériennes/complications , Inflammation/complications , BiopsieRÉSUMÉ
Late anti-toxin-B humoral immunity acquired after treatment is important for preventing recurrent Clostridioides difficile infection. We prospectively-measured anti-toxin-B IgG and neutralization titers at diagnosis as potential early predictors of recurrence. High anti-toxin-B-IgG/neutralizing antibodies were associated with short-lasting protection within 6-weeks, however, no difference in recurrence risk was observed by 90-days post-infection.
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Anticorps antibactériens , Toxines bactériennes , Clostridioides difficile , Infections à Clostridium , Immunoglobuline G , Récidive , Infections à Clostridium/immunologie , Infections à Clostridium/prévention et contrôle , Humains , Immunoglobuline G/sang , Immunoglobuline G/immunologie , Toxines bactériennes/immunologie , Clostridioides difficile/immunologie , Anticorps antibactériens/sang , Anticorps antibactériens/immunologie , Mâle , Adulte d'âge moyen , Femelle , Sujet âgé , Protéines bactériennes/immunologie , Études prospectives , Anticorps neutralisants/immunologie , Anticorps neutralisants/sang , Adulte , Sujet âgé de 80 ans ou plusRÉSUMÉ
OBJECTIVES: Clostridioides difficile infection (CDI) is characterized by neutrophilia in blood, with a high leukocyte count accompanying severe infection. In this study, we characterized peripheral blood neutrophil activation and maturity in CDI by (i) developing a method to phenotype stored neutrophils for disease-related developmental alterations and (ii) assessing neutrophil-associated biomarkers. METHODS: We stored fixed leukocytes from blood collected within 24 h of diagnosis from a cohort of hospitalized patients with acute CDI. Additional study cohorts included recurrent CDI patients at time of and two months after FMT therapy and a control healthy cohort. We assessed levels of neutrophil surface markers CD66b, CD11b, CD16 and CD10 by flow cytometry. Plasma neutrophil elastase and lipocalin-2 were measured using ELISA, while G-CSF, GM-CSF and cytokines were measured using O-link Proteomic technology. RESULTS: CD66b+ neutrophil abundance assessed by flow cytometry correlated well with complete blood counts, establishing that neutrophils in stored blood are sufficiently well-preserved for phenotyping by flow cytometry. Neutrophil abundance was significantly increased in CDI patients compared to healthy controls. Emergency granulopoiesis in acute CDI patients was evidenced by lower neutrophil surface expression of CD10, CD11b and CD16. CD10+ staining of neutrophils started to recover within 3-7 days of CDI treatment. Neutrophil activation and degranulation were higher in acute CDI as assessed by plasma neutrophil elastase and lipocalin-2. Biomarker levels in immunocompetent subjects were associated with recurrence and fatal outcomes. CONCLUSIONS: Neutrophil activation and emergency granulopoiesis characterize the early immune response in acute CDI, with plasma degranulation biomarkers predictive of disease severity.
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Dégranulation cellulaire , Clostridioides difficile , Infections à Clostridium , Granulocytes neutrophiles , Humains , Granulocytes neutrophiles/immunologie , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Infections à Clostridium/immunologie , Infections à Clostridium/sang , Infections à Clostridium/microbiologie , Marqueurs biologiques/sang , Adulte , Cytométrie en flux , Activation des neutrophiles , Sujet âgé de 80 ans ou plus , Cytokines/sang , Lipocaline-2/sangRÉSUMÉ
OBJECTIVES: Clostridioides difficile infection (CDI) is the leading hospital-acquired infection in North America. While previous work on fecal microbiota transplantation (FMT), a highly effective treatment for CDI, has focused on colonization resistance mounted against C. difficile by FMT-delivered commensals, the effects of FMT on host gene expression are relatively unexplored. This study aims to identify transcriptional changes associated with FMT, particularly changes associated with protective immune responses. METHODS: Gene expression was assessed on day 2 and day 7 after FMT in mice after antibiotic-induced dysbiosis. Flow cytometry was also performed on colon and mesenteric lymph nodes at day 7 to investigate changes in immune cell populations. RESULTS: FMT administration after antibiotic-induced dysbiosis successfully restored microbial alpha diversity to levels of donor mice by day 7 post-FMT. Bulk RNA sequencing of cecal tissue at day 2 identified immune genes, including both pro-inflammatory and Type 2 immune pathways as upregulated after FMT. RNA sequencing was repeated on day 7 post-FMT, and expression of these immune genes was decreased along with upregulation of genes associated with restoration of intestinal homeostasis. Immunoprofiling on day 7 identified increased colonic CD45+ immune cells that exhibited dampened Type 1 and heightened regulatory and Type 2 responses. These include an increased abundance of eosinophils, alternatively activated macrophages, Th2, and T regulatory cell populations. CONCLUSION: These results highlight the impact of FMT on host gene expression, providing evidence that FMT restores intestinal homeostasis after antibiotic treatment and facilitates tolerogenic and Type 2 immune responses.
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Infections à Clostridium , Modèles animaux de maladie humaine , Transplantation de microbiote fécal , Animaux , Transplantation de microbiote fécal/méthodes , Souris , Infections à Clostridium/thérapie , Infections à Clostridium/immunologie , Infections à Clostridium/microbiologie , Microbiome gastro-intestinal , Dysbiose/thérapie , Clostridioides difficile/immunologie , Tolérance immunitaire , Souris de lignée C57BLRÉSUMÉ
Innate lymphoid cells (ILCs) play a critical role in maintaining intestinal health in homeostatic and diseased conditions. During Clostridium difficile infection (CDI), IL-33 activates ILC2 to protect from colonic damage and mortality. The function of IL-33 and ILC is tightly regulated by the intestinal microbiota. We set out to determine the impact of antibiotic-induced disruption of the microbiome on ILC function. Our goal was to understand antibiotic-induced changes in ILC function on susceptibility to C. difficile colitis in a mouse model. We utilized high-throughput single-cell RNAseq to investigate the phenotypic features of colonic ILC at baseline, after antibiotic administration with or without IL-33 treatment. We identified a heterogeneous landscape of colonic ILCs with gene signatures of inflammatory, anti-inflammatory, migratory, progenitor, plastic, and antigen-presenting ILCs. Antibiotic treatment decreased ILC2 while coordinately increasing ILC1 and ILC3 phenotypes. Notably, Ifng+, Ccl5+, and Il23r+ ILC increased after antibiotics. IL-33 treatment counteracted the antibiotic effect by downregulating ILC1 and ILC3 and activating ILC2. In addition, IL-33 treatment markedly induced the expression of type 2 genes, including Areg and Il5. Finally, we identified amphiregulin, produced by ILC2, as protective during C. difficile infection. Together, our data expand our understanding of how antibiotics induce susceptibility to C. difficile colitis through their impact on ILC subsets and function.IMPORTANCEClostridium difficile infection (CDI) accounts for around 500,000 symptomatic cases and over 20,000 deaths annually in the United States alone. A major risk factor of CDI is antibiotic-induced dysbiosis of the gut. Microbiota-regulated IL-33 and innate lymphoid cells (ILCs) are important in determining the outcomes of C. difficile infection. Understanding how antibiotic and IL-33 treatment alter the phenotype of colon ILCs is important to identify potential therapeutics. Here, we performed single-cell RNAseq of mouse colon ILCs collected at baseline, after antibiotic treatment, and after IL-33 treatment. We identified heterogeneous subpopulations of all three ILC subtypes in the mouse colon. Our analysis revealed several potential pathways of antibiotic-mediated increased susceptibility to intestinal infection. Our discovery that Areg is abundantly expressed by ILCs, and the protection of mice from CDI by amphiregulin treatment, suggests that the amphiregulin-epidermal growth factor receptor pathway is a potential therapeutic target for treating intestinal colitis.
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Clostridioides difficile , Infections à Clostridium , Colite , Entérocolite pseudomembraneuse , Souris , Animaux , Immunité innée , Lymphocytes , Antibactériens/pharmacologie , Interleukine-33/métabolisme , Interleukine-33/pharmacologie , Amphiréguline/métabolisme , Amphiréguline/pharmacologie , Dysbiose , Infections à Clostridium/métabolismeRÉSUMÉ
Exposure to psychosocial adversity (PA) is associated with poor behavioral, physical, and mental health outcomes in adulthood. Growing evidence suggests that deficits in executive functions may in part moderate these outcomes, with inhibitory control as an example of such a putative moderator. However, much of the literature examining the development of inhibitory control has been based on children in higher resource environments, and little is known how growing up in a low resource setting might exacerbate the link between inhibitory control and health outcomes. In this context we collected fMRI data during a Go/No-Go inhibitory control task and PA variables for 68 children 5 to 7 years of age living in Dhaka, Bangladesh, an area with a high prevalence of PA. The children's mothers completed behavioral questionnaires to assess the child's PA and their own PA. Whole-brain activation underlying inhibitory control was examined using the No-Go versus Go contrast, and associations with PA variables were assessed using whole-brain regressions. Childhood neglect was associated with weaker activation in the right posterior cingulate, whereas greater family conflict, economic stress, and maternal PA factors were associated with greater activation in the left medial frontal gyrus, right superior and middle frontal gyrus, and left cingulate gyrus. These data suggest that neural networks supporting inhibitory control processes may vary as a function of exposure to different types of PA, particularly between those related to threat and deprivation. Furthermore, increased activation in children with greater PA may serve as a compensatory mechanism, allowing them to maintain similar behavioral task performance.
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Background: Early diagnosis of late-onset sepsis (LOS) and necrotizing enterocolitis (NEC) in very low birth weight (VLBW, <1,500â g) infants is challenging due to non-specific clinical signs. Inflammatory biomarkers increase in response to infection, but non-infectious conditions also cause inflammation. Cardiorespiratory data contain physiological biomarkers, or physiomarkers, of sepsis that may be useful in combination with inflammatory hematologic biomarkers for sepsis diagnosis. Objectives: To determine whether inflammatory biomarkers measured at the time of LOS or NEC diagnosis differ from times without infection and whether biomarkers correlate with cardiorespiratory sepsis physiomarkers in VLBW infants. Methods: Remnant plasma sample collection from VLBW infants occurred with blood draws for routine laboratory testing and suspected sepsis. We analyzed 11 inflammatory biomarkers and a pulse oximetry sepsis warning score (POWS). We compared biomarker levels obtained at the time of gram-negative (GN) bacteremia or NEC, gram-positive (GP) bacteremia, negative blood cultures, and no suspected infection. Results: We analyzed 188 samples in 54 VLBW infants. Several biomarkers were increased at the time of GN LOS or NEC diagnosis compared with all other samples. POWS was higher in patients with LOS and correlated with five biomarkers. IL-6 had 78% specificity at 100% sensitivity to detect GN LOS or NEC and added information to POWS. Conclusions: Inflammatory plasma biomarkers discriminate sepsis due to GN bacteremia or NEC and correlate with cardiorespiratory physiomarkers.
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Background: We previously conducted a phase 2a randomized placebo-controlled trial of 40 subjects to assess the efficacy and safety of dupilumab use in people hospitalized with coronavirus disease 2019 (COVID-19) (NCT04920916). Based on our preclinical data suggesting that downstream pulmonary dysfunction with COVID-19 induced type 2 inflammation, we contacted patients from our phase 2a study at 1 year for assessment of post-COVID-19 conditions. Methods: Subjects at 1 year after treatment underwent pulmonary function tests, high-resolution computed tomographic imaging, symptom questionnaires, neurocognitive assessments, and serum immune biomarker analysis, with subject survival also monitored. The primary outcome was the proportion of abnormal diffusion capacity for carbon monoxide (DLCO) or 6-minute walk test (6MWT) at the 1-year visit. Results: Of those survivors who consented to 1-year visits (n = 16), subjects who had originally received dupilumab were less likely than those who received placebo to have an abnormal DLCO or 6MWT (Fisher exact P = .011; adjusted P = .058). As a secondary endpoint, we saw that 16% of subjects in the dupilumab group died by 1 year compared to 38% in the placebo group, though this was not statistically significant (log-rank P = .12). We did not find significant differences in neurocognitive testing, symptoms, or chest computed tomography between treatment groups but observed a larger reduction in eotaxin levels in those who received dupilumab. Conclusions: In this observational study, subjects who received dupilumab during acute COVID-19 hospitalization were less likely to have a reduced DLCO or 6MWT, with a nonsignificant trend toward reduced mortality at 1 year compared to placebo.
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Hyaluronan (HA), an extracellular matrix polysaccharide, is increased in the lungs during COVID-19 and correlates with severity. HA acts as an immune mediator that aids cell trafficking and intracellular signaling, but its role in COVID-19 is debated. Although HA is implicated in pulmonary viral disease pathogenesis, some studies suggest a potential protective function in COVID-19.
Sujet(s)
COVID-19 , Acide hyaluronique , Humains , Poumon , Matrice extracellulaire , Transduction du signalRÉSUMÉ
BACKGROUND: An incomplete understanding of preterm birth is especially concerning for low-middle income countries, where preterm birth has poorer prognoses. While systemic proinflammatory processes are a reportedly normal component of gestation, excessive inflammation has been demonstrated as a risk factor for preterm birth. There is minimal research on the impact of excessive maternal inflammation in the first trimester on the risk of preterm birth in low-middle income countries specifically. METHODS: Pregnant women were enrolled at the rural Bangladesh site of the National Institute of Child Health Global Network Maternal Newborn Health Registry. Serum samples were collected to measure concentrations of the inflammatory markers C-reactive protein (CRP) and Alpha-1-acid glycoprotein (AGP), and stool samples were collected and analyzed for enteropathogens. We examined associations of maternal markers in the first-trimester with preterm birth using logistic regression models. CRP and AGP were primarily modeled with a composite inflammation predictor. RESULTS: Out of 376 singleton births analyzed, 12.5% were preterm. First trimester inflammation was observed in 58.8% of all births, and was significantly associated with increased odds of preterm birth (adjusted odds ratio [aOR] = 2.23; 95% confidence interval [CI]: 1.03, 5.16), independent of anemia. Maternal vitamin B12 insufficiency (aOR = 3.33; 95% CI: 1.29, 8.21) and maternal anemia (aOR = 2.56; 95% CI: 1.26, 5.17) were also associated with higher odds of preterm birth. Atypical enteropathogenic E. coli detection showed a significant association with elevated AGP levels and was significantly associated with preterm birth (odds ratio [OR] = 2.36; 95% CI: 1.21, 4.57), but not associated with CRP. CONCLUSIONS: Inflammation, anemia, and vitamin B12 insufficiency in the first trimester were significantly associated with preterm birth in our cohort from rural Bangladesh. Inflammation and anemia were independent predictors of premature birth in this low-middle income setting where inflammation during gestation was widespread. Further research is needed to identify if infections such as enteropathogenic E. coli are a cause of inflammation in the first trimester, and if intervention for infection would decrease preterm birth.