Validation of collection and anaerobic fermentation techniques for measuring prebiotic impact on gut microbiota

BACKGROUND

Defining the ability of prebiotic dietary carbohydrates to influence the composition and metabolism of the gut microbiota is central to defining their health impact in diverse individuals. Many clinical trials are using indirect methods. This study aimed to validate collection and fermentation methods enabling their use in the context of clinical studies.

METHODS AND RESULTS

Parameters tested included stool sample acquisition, storage, and growth conditions. Stool from 3 infants and 3 adults was collected and stored under varying conditions. Samples were cultured anaerobically for two days in the presence of prebiotics, whereupon optical density and pH were measured across time. Whole genome shotgun sequencing and NMR metabolomics were performed. Neither the type of collection vial (standard vial and two different BD anaerobic collection vials) nor cryopreservation (-80 °C or 4 °C) significantly influenced either microbial composition at 16 h of anaerobic culture or the principal components of the metabolome at 8 or 16 h. Metagenomic differences were driven primarily by subject, while metabolomic differences were driven by fermentation sugar (2'-fucosyllactose or dextrose).

CONCLUSIONS

These data identified a feasible and valid approach for prebiotic fermentation analysis of individual samples in large clinical studies: collection of stool microbiota using standard vials; cryopreservation prior to testing; and collecting fermentation read-out at 8 and 16 hr. Thus, fermentation analysis can be a valid technique for testing the effects of prebiotics on human fecal microbiota.

Human Milk Oligosaccharides and Respiratory Syncytial Virus Infection in Infants

In infants worldwide, respiratory syncytial virus (RSV) is the leading cause of lower respiratory infections, including bronchiolitis, which is a major source of infant mortality. Bronchiolitis is the most common lower respiratory infection and the major cause of hospitalization in the first 6 mo of life. Infant responses to RSV infection are highly diverse, with symptoms varying from asymptomatic or mild to so severe as to require mechanical ventilation. Breastfed infants present a lower incidence and less severe forms of RSV lower respiratory infections. Among the multitude of human milk bioactive compounds, human milk oligosaccharides (hMOSs) are strong candidates for having a protective effect against RSV. hMOS reduces the viral load and the inflammatory signaling in cultured RSV-infected respiratory human cells. In addition to this direct effect, indirect mechanisms, notably gut microbiota composition and metabolism, have been proposed to mediate the protective effect of hMOS. Intake of infant formula containing synthetic hMOS has been shown to increase Bifidobacterium abundance and that of its metabolites, especially acetate, in infant feces and to reduce lower respiratory tract infections during the first year of life. Breastfeeding and the use of hMOS are promising approaches to protect against and treat RSV disease. Here, we review current evidence on the role of hMOS with regard to RSV infection and disease, attending to knowledge gaps and future research directions.

Factors Associated With Prolonged Respiratory Virus Detection From Polymerase Chain Reaction of Nasal Specimens Collected Longitudinally in Healthy Children in a US Birth Cohort

BACKGROUND

Respiratory viral shedding is incompletely characterized by existing studies due to the lack of longitudinal nasal sampling and limited inclusion of healthy/asymptomatic children. We describe characteristics associated with prolonged virus detection by polymerase chain reaction (PCR) in a community-based birth cohort.

METHODS

Children were followed from birth to 2 years of age in the PREVAIL cohort. Weekly nasal swabs were collected and tested using the Luminex Respiratory Pathogen Panel. Weekly text surveys were administered to ascertain the presence of acute respiratory illnesses defined as fever and/or cough. Maternal reports and medical chart abstractions identified healthcare utilization. Prolonged virus detection was defined as a persistently positive test lasting ≥4 weeks. Factors associated with prolonged virus detection were assessed using mixed effects multivariable logistic regression.

RESULTS

From a sub-cohort of 101 children with ≥70% weekly swabs collected, a total of 1489 viral infections were detected. Prolonged virus detection was found in 23.4% of viral infections overall, 39% of bocavirus infections, 33% of rhinovirus/enterovirus infections, 14% of respiratory syncytial virus (RSV) A infections, and 7% of RSV B infections. No prolonged detection was found for influenza virus A or B, coronavirus 229E or HKU1, and parainfluenza virus 2 or 4 infections. First-lifetime infection with each virus, and co-detection of another respiratory virus were significantly associated with prolonged detection, while symptom status, child sex, and child age were not.

CONCLUSIONS

Prolonged virus detection was observed in 1 in 4 viral infections in this cohort of healthy children and varied by pathogen, occurring most often for bocavirus and rhinovirus/enterovirus. Evaluating the immunological basis of how viral co-detections and recurrent viral infections impact duration of virus detection by PCR is needed to better understand the dynamics of prolonged viral shedding.

Endemic coronavirus infections are associated with strong homotypic immunity in a US cohort of children from birth to 4 years

BACKGROUND

The endemic coronaviruses OC43, HKU1, NL63 and 229E cause cold-like symptoms and are related to SARS-CoV-2, but their natural histories are poorly understood. In a cohort of children followed from birth to 4 years, we documented all coronavirus infections, including SARS-CoV-2, to understand protection against subsequent infections with the same virus (homotypic immunity) or a different coronavirus (heterotypic immunity).

METHODS

Mother-child pairs were enrolled in metropolitan Cincinnati during the third trimester of pregnancy in 2017-18. Mothers reported their child's socio-demographics, risk factors, and weekly symptoms. Mid-turbinate nasal swabs were collected weekly. Blood was collected at 6 weeks, 6, 12, 18, 24 months and annually thereafter. Infections were detected by testing nasal swabs by an RT-PCR multi-pathogen panel and by serum IgG responses. Health care visits were documented from pediatric records. Analysis was limited to 116 children with high sample adherence. Re-consent for monitoring SARS-CoV-2 infections from June 2020 through November 2021 was obtained for 74 (64%) children.

RESULTS

We detected 345 endemic coronavirus infections (1.1 infections/child-year) and 21 SARS-CoV-2 infections (0.3 infections/child-year). Endemic coronavirus and SARS-CoV-2 infections were asymptomatic or mild. Significant protective homotypic immunity occurred after a single infection with OC43 (77%) and HKU1 (84%), and after two infections with NL63 (73%). No heterotypic protection against endemic coronaviruses or SARS-CoV-2 was identified.

CONCLUSIONS

Natural coronavirus infections were common and resulted in strong homotypic immunity but not heterotypic immunity against other coronaviruses, including SARS-CoV-2. Endemic coronavirus and SARS-CoV-2 infections in this US cohort were typically asymptomatic or mild.

Correlates of Rotavirus Vaccine Shedding and Seroconversion in a U.S. Cohort of Healthy Infants

BACKGROUND

Rotavirus is a leading cause of severe pediatric gastroenteritis; two highly effective vaccines are used in the US. We aimed to identify correlates of immune response to rotavirus vaccination in a US cohort.

METHODS

PREVAIL is a birth cohort of 245 mother-child pairs enrolled 2017-2018 and followed for 2 years. Infant stool samples and symptom information were collected weekly. Shedding was defined as RT-PCR detection of rotavirus vaccine virus in stools collected 4-28 days after dose one. Seroconversion was defined as a threefold rise in IgA between the six-week and six-month blood draws. Correlates were analyzed using generalized estimating equations and logistic regression.

RESULTS

Pre-vaccination IgG (OR=0.84, 95% CI [0.75-0.94] per 100-unit increase) was negatively associated with shedding. Shedding was also less likely among infants with a single-nucleotide polymorphism inactivating FUT2 antigen secretion ("non-secretors") with non-secretor mothers, versus all other combinations (OR 0.37 [0.16-0.83]). Of 141 infants with data, 105 (74%) seroconverted; 78 (77%) had shed vaccine virus following dose one. Pre-vaccination IgG and secretor status were significantly associated with seroconversion. Neither shedding nor seroconversion significantly differed by vaccine product.

DISCUSSION

In this US cohort, pre-vaccination IgG and maternal and infant secretor status were associated with rotavirus vaccine response.

Obesity and Prenatal Intention as Predictors of Meeting Breastfeeding Recommendations in an Urban Birth Cohort

Background and Objectives: Few U.S. women meet the public health recommendations to exclusively breastfeed for 6 months and continue breastfeeding for at least 1-2 years. We compared prenatally collected demographic, health, and breastfeeding support/intention variables to examine how these factors intersect to predict meeting breastfeeding recommendations. Methods: PREVAIL, a CDC-funded birth cohort in Cincinnati, OH, was approved by the IRB at CDC, Cincinnati Children's Hospital, and the hospitals where enrollment (third trimester, 2017-2018) occurred. The prenatal questionnaire captured sociodemographics, pre-pregnancy weight and height, breastfeeding environment, and breastfeeding intention, while health factors were obtained from obstetrical records. Body mass index (BMI) (kg/m2) was categorized as healthy (18.5-24.9), overweight (25-29.9), obesity 1 (30-34.9), and obesity 2+ (≥35). Mothers self-reported date of exclusive and any breastfeeding cessation through quarterly postnatal questionnaires. Random forest was used for variable selection, cross-validated in multivariable logistic models. Results: Analysis included n = 237 mothers with BMI ≥18.5. Random forest identified BMI category, prenatal intention, and insurance type as the most important predictors of meeting breastfeeding recommendations. The resulting logistic models explained >40% of the variance with an area under the curve of ≥0.89 for both recommendations. More than 73% of the risk of not meeting breastfeeding recommendations was attributable to having an elevated BMI or lacking strong breastfeeding intention. Conclusions: In PREVAIL, maternal BMI and prenatal intention explained most risks of not meeting breastfeeding exclusivity and duration recommendations. Our findings suggest efforts to improve breastfeeding exclusivity and duration should focus on strengthening prenatal breastfeeding intention and identifying effective interventions for supporting breastfeeding among mothers with higher BMI.

A novel LC-MS/MS method to characterize the antimicrobial lipid glycerol monolaurate in global human milk

Glycerol monolaurate (GML), a monoglyceride found in human milk (HM), has antimicrobial properties against a broad spectrum of bacteria, viruses, and fungi. In this study, an LC-MS/MS method was developed and validated for quantifying GML in HM based on quantification of two distinct isomers, 1-monolaurin and 2-monolaurin. The method validation included assessments of selectivity (no interferences), linearity (r2 range of 0.9954- 0.9985 and 96 of 98 individual points having residual <15%), accuracy (average recovery of 96.4% across both isomers and a range of spiked levels), and precision (total GML repeatability 6.6% RSD and intermediate precision 9.7% RSD). This validated method was used to measure the concentration of GML in unpasteurized HM from 60 mothers and compared geographical locations (Cincinnati and Shanghai), lactation time (weeks 2 and 26), and self-reported maternal allergy status (yes or no). Our findings suggest GML concentration in unpasteurized HM is considerably lower than previously reported in a study characterizing pasteurized HM. The data reported here highlights a novel, validated method used to quantify GML in HM and identified no differences in total GML concentrations when comparing HM from different geographical locations, lactation times, and mother's allergy status.

Associations Between Breastfeeding and Post-perinatal Infant Deaths in the U.S

INTRODUCTION

Initiation of breastfeeding has been associated with reduced post-perinatal infant mortality. Although most states have initiatives to protect, promote, and support breastfeeding, no analysis of the association between breastfeeding and infant mortality has been conducted at the state and regional levels. To understand the associations between breastfeeding and post-perinatal infant mortality, the initiation of breastfeeding with post-perinatal infant mortality was analyzed by geographic region and individual states within each region.

METHODS

This study was a prospective cohort analysis linking U.S. national birth and post-perinatal infant death data for nearly 10 million infants born in 2016-2018, who were then followed for one year after birth and analyzed in 2021-2022.

RESULTS

A total of 9,711,567 live births and 20,632 post-perinatal infant deaths from 48 states and the District of Columbia were included in the analysis. The overall AOR and 95% CIs for breastfeeding initiation with post-perinatal infant mortality was 0.67 (0.65, 0.69, p<0.0001) for days 7-364. All seven U.S. geographic regions had significant reductions in postperinatal infant deaths associated with breastfeeding initiation; Mid-Atlantic and Northeast regions had the largest reductions with AOR of 0.56 (95% CI=0.51, 0.61, p<0.001 and 0.50, 0.63, p<0.001, respectively), whereas the Southeast had the smallest reduction with AOR of 0.79 (95% CI=0.75, 0.84, p<0.001). Statistically significant results were noted for 35 individual states for reduction in total post-perinatal infant deaths.

CONCLUSIONS

Although regional and state variation in the magnitude of the association between breastfeeding and infant mortality exists, the consistency of reduced risk, together with existing literature, suggests that breastfeeding promotion and support may be a strategy to reduce infant mortality in the U.S.

Burden of Respiratory Viruses in Children Less Than 2 Years Old in a Community-based Longitudinal US Birth Cohort

BACKGROUND

Respiratory viral infections are a major cause of morbidity and hospitalization in young children. Nevertheless, the population burden of respiratory viral infections, especially asymptomatic cases, is not known due to the lack of prospective community-based cohort studies with intensive monitoring.

METHODS

To address this gap, we enacted the PREVAIL cohort, a Centers for Disease Control and Prevention-sponsored birth cohort in Cincinnati, Ohio, where children were followed from 0 to 2 years of age. Weekly text surveys were administered to record acute respiratory illnesses (ARIs), which were defined as the presence of cough or fever (≥38°C). Weekly midturbinate nasal swabs were collected and tested using the Luminex Respiratory Pathogen Panel, which detected 16 viral pathogens. Viral infection was defined as ≥1 positive tests from the same virus or viral subtype ≤30 days of a previous positive test. Maternal report and medical chart abstractions identified healthcare utilization.

RESULTS

From 4/2017 to 7/2020, 245 mother-infant pairs were recruited and followed. From the 13 781 nasal swabs tested, a total of 2211 viral infections were detected, of which 821 (37%) were symptomatic. Children experienced 9.4 respiratory viral infections/child-year; half were rhinovirus/enterovirus. Viral ARI incidence was 3.3 episodes/child-year. Emergency department visits or hospitalization occurred with only 15% of respiratory syncytial virus infections, 10% of influenza infections, and only 4% of all viral infections. Regardless of pathogen, most infections were asymptomatic or mild.

CONCLUSIONS

Respiratory viral infections are common in children 0-2 years. Most viral infections are asymptomatic or non-medically attended, underscoring the importance of community-based cohort studies.

The human milk component myo-inositol promotes neuronal connectivity

Effects of micronutrients on brain connectivity are incompletely understood. Analyzing human milk samples across global populations, we identified the carbocyclic sugar myo-inositol as a component that promotes brain development. We determined that it is most abundant in human milk during early lactation when neuronal connections rapidly form in the infant brain. Myo-inositol promoted synapse abundance in human excitatory neurons as well as cultured rat neurons and acted in a dose-dependent manner. Mechanistically, myo-inositol enhanced the ability of neurons to respond to transsynaptic interactions that induce synapses. Effects of myo-inositol in the developing brain were tested in mice, and its dietary supplementation enlarged excitatory postsynaptic sites in the maturing cortex. Utilizing an organotypic slice culture system, we additionally determined that myo-inositol is bioactive in mature brain tissue, and treatment of organotypic slices with this carbocyclic sugar increased the number and size of postsynaptic specializations and excitatory synapse density. This study advances our understanding of the impact of human milk on the infant brain and identifies myo-inositol as a breast milk component that promotes the formation of neuronal connections.

Prenatal SARS-CoV-2 infection alters postpartum human milk-derived extracellular vesicles

Human milk-derived extracellular vesicles (HMEVs) are crucial functional components in breast milk, contributing to infant health and development. Maternal conditions could affect HMEV cargos; however, the impact of SARS-CoV-2 infection on HMEVs remains unknown. This study evaluated the influence of SARS-CoV-2 infection during pregnancy on postpartum HMEV molecules. Milk samples (9 prenatal SARS-CoV-2 vs. 9 controls) were retrieved from the IMPRINT birth cohort. After defatting and casein micelle disaggregation, 1 mL milk was subjected to a sequential process of centrifugation, ultrafiltration, and qEV-size exclusion chromatography. Particle and protein characterizations were performed following the MISEV2018 guidelines. EV lysates were analyzed through proteomics and miRNA sequencing, while the intact EVs were biotinylated for surfaceomic analysis. Multi-Omics was employed to predict HMEV functions associated with prenatal SARS-CoV-2 infection. Demographic data between the prenatal SARS-CoV-2 and control groups were similar. The median duration from maternal SARS-CoV-2 test positivity to milk collection was 3 months (range: 1-6 months). Transmission electron microscopy showed the cup-shaped nanoparticles. Nanoparticle tracking analysis demonstrated particle diameters of <200 nm and yields of >1e11 particles from 1 mL milk. Western immunoblots detected ALIX, CD9 and HSP70, supporting the presence of HMEVs in the isolates. Thousands of HMEV cargos and hundreds of surface proteins were identified and compared. Multi-Omics predicted that mothers with prenatal SARS-CoV-2 infection produced HMEVs with enhanced functionalities involving metabolic reprogramming and mucosal tissue development, while mitigating inflammation and lower EV transmigration potential. Our findings suggest that SARS-CoV-2 infection during pregnancy boosts mucosal site-specific functions of HMEVs, potentially protecting infants against viral infections. Further prospective studies should be pursued to reevaluate the short- and long-term benefits of breastfeeding in the post-COVID era.

ALA-A2 Is a Novel Anticancer Peptide Inspired by Alpha-Lactalbumin: A Discovery from a Computational Peptide Library, In Silico Anticancer Peptide Screening and In Vitro Experimental Validation

Anticancer peptides (ACPs) are rising as a new strategy for cancer therapy. However, traditional laboratory screening to find and identify novel ACPs from hundreds to thousands of peptides is costly and time consuming. Here, a sequential procedure is applied to identify candidate ACPs from a computer-generated peptide library inspired by alpha-lactalbumin, a milk protein with known anticancer properties. A total of 2688 distinct peptides, 5-25 amino acids in length, are generated from alpha-lactalbumin. In silico ACP screening using the physicochemical and structural filters and three machine learning models lead to the top candidate peptides ALA-A1 and ALA-A2. In vitro screening against five human cancer cell lines supports ALA-A2 as the positive hit. ALA-A2 selectively kills A549 lung cancer cells in a dose-dependent manner, with no hemolytic side effects, and acts as a cell penetrating peptide without membranolytic effects. Sequential window acquisition of all theorical fragment ions-proteomics and functional validation reveal that ALA-A2 induces autophagy to mediate lung cancer cell death. This approach to identify ALA-A2 is time and cost-effective. Further investigations are warranted to elucidate the exact intracellular targets of ALA-A2. Moreover, these findings support the use of larger computational peptide libraries built upon multiple proteins to further advance ACP research and development.

Gut Microbiome Composition and Metabolic Capacity Differ by FUT2 Secretor Status in Exclusively Breastfed Infants

A major polymorphism in the fucosyltransferase2 (FUT2) gene influences risk of multiple gut diseases, but its impact on the microbiome of breastfed infants was unknown. In individuals with an active FUT2 enzyme (“secretors”), the intestinal mucosa is abundantly fucosylated, providing mutualist bacteria with a rich endogenous source of fucose. Non-secretors comprise approximately one-fifth of the population, and they lack the ability to create this enzyme. Similarly, maternal secretor status influences the abundance of a breastfeeding mother’s fucosylated milk oligosaccharides. We compared the impact of maternal secretor status, measured by FUT2 genotype, and infant secretor status, measured by FUT2 genotype and phenotype, on early infant fecal microbiome samples collected from 2-month-old exclusively breastfed infants (n = 59). Infant secretor status (19% non-secretor, 25% low-secretor, and 56% full-secretor) was more strongly associated with the infant microbiome than it was with the maternal FUT2 genotype. Alpha diversity was greater in the full-secretors than in the low- or non-secretor infants (p = 0.049). Three distinct microbial enterotypes corresponded to infant secretor phenotype (p = 0.022) and to the dominance of Bifidobacterium breve, B. longum, or neither (p < 0.001). Infant secretor status was also associated with microbial metabolic capacity, specifically, bioenergetics pathways. We concluded that in exclusively breastfed infants, infant—but not maternal—secretor status is associated with infant microbial colonization and metabolic capacity.

92. Incidence of Adenovirus Respiratory Infection and Coinfection in a Longitudinal Birth Cohort

Background

Adenoviruses (AdVs) are a common cause of acute respiratory illness (ARI) in children and are often detected with other viruses (coinfection). However, the community incidence of AdV infections is poorly understood due to a lack of prospective studies outside the hospital setting. Here, we aim to characterize respiratory AdV infections and coinfections in a prospective birth cohort of children.

Methods

The PREVAIL cohort is a CDC-funded, 2-year birth cohort, conducted from 2017–2020 in Cincinnati, OH. ARI was defined as the presence of cough or fever identified with weekly maternal text surveys and medical chart review. Mid-turbinate nasal swabs were collected weekly. Swabs were tested using Luminex Respiratory Pathogen Panel. AdV infection was defined as a swab positive for AdV and included subsequent positives < 30 days apart. Coinfection was defined as detection of any other virus(es) during an AdV infection. Children who submitted at least 70% of weekly samples were included in our analysis.

Results

101 children met inclusion criteria, representing 165 child-years. 137 distinct AdV infections were identified (incidence 0.84 infections per child year), with 98 (97%) children having ≥1 AdV infection. Only 40% (n=55) of AdV infections were symptomatic. Of those with symptomatic infections, 51% (n=28) sought medical care, with 42% (n=23) presenting to a primary care provider and 9% (n=5) resulting in an ED visit or hospital admission. Coinfections were detected in 67% (n=92) of AdV infections, with 45% (n=62) coinfected with 1 virus, 19% (n=26) with 2 viruses, and 3% (n=4) with ≥3 viruses. 77% of coinfections (n=71) were rhino/enterovirus. The number of coinfections or the specific coinfection virus was not associated with an increase in symptom prevalence or symptom severity (all p > 0.05).

Viral Coinfection Frequency with Adenovirus Infection in the PREVAIL Cohort.

Adenovirus Infection and Coinfection in the PREVAIL Cohort.

Conclusion

In this cohort of healthy children, AdVs were a common cause of respiratory infection. Most infections were asymptomatic or resulted in mild symptoms. Two-thirds of AdV infections involved viral coinfections, but coinfection was not associated with more frequent or severe symptoms. Our findings suggest studies that only include symptomatic or hospitalized patients may overestimate AdVs disease severity.

Disclosures

All Authors: No reported disclosures.

95. Prolonged respiratory viral infection associated with presence of coinfections in an urban birth cohort

Background

Prolonged infection by respiratory viruses has been reported, especially in hospitalized or immunocompromised children. However, little is known of factors contributing to prolonged respiratory viral infection, particularly in asymptomatic and less severe infections. We examined characteristics associated with prolonged viral infection in a community-based birth cohort.

Methods

The PREVAIL cohort is a CDC-sponsored two-year birth cohort in Cincinnati, Ohio conducted during 4/2017 to 8/2020. Mid-turbinate nasal swabs were collected weekly from children and tested using the Luminex Respiratory Pathogen Panel. The primary outcome was prolonged viral infection, which was defined as a viral nucleic acid detection lasting 4 or more weeks. Proportions of prolonged viral infections were compared using Fisher’s exact test with Holms corrections. Adjusted odds ratios (aOR) and 95% confidence intervals were calculated using a mixed effects logistic regression model while controlling for within-subject clustering, viral species, child age, child sex, symptom status, and coinfection. This analysis was limited to subjects who provided at least 70% of weekly samples.

Results

Among 101 children, providing 7871 child-weeks of follow-up, we identified 780 viral infections. The median duration of infection across all respiratory viruses was 1 week, except for bocavirus and coronavirus NL63, each with 2 weeks; 40% of bocavirus and >10% of adenovirus, coronavirus NL63, RSV A, human metapneumovirus, and parainfluenza 1 infections were associated with prolonged infection (>4 weeks). No prolonged infections were detected for influenza A or B, coronavirus 229E or HKU1, or parainfluenza 2 or 4 infections. Viral coinfection (aOR=3.1, 95% CI 1.9, 5.0) and female sex (aOR 1.8, 95%CI 1.1, 2.9) were significantly associated with prolonged infection, while symptom status and child age were not.

Conclusion

In the PREVAIL cohort, detection of respiratory viruses lasting 4 weeks or longer was common for certain respiratory pathogens and was especially prolonged for bocavirus. Biological factors such as the presence of additional viral infections or child sex may affect the likelihood of prolonged infection.

Disclosures

All Authors: No reported disclosures.

Neighbourhood socio-economic environment predicts adiposity and obesity risk in children under two

BACKGROUND

Neighbourhood socio-economic environment (SEE) is associated with obesity in older children and adults, but little is known about this relationship in younger children. Breastfeeding is an important preventative of adiposity in childhood, but its relationship with neighbourhood SEE is unknown.

AIMS

We assessed differences in adiposity and obesity in children before age two by neighbourhood SEE, controlling for family socio-demographics and breastfeeding duration.

MATERIALS AND METHODS

Family socio-demographics, child body mass index z scores (BMIz), and breastfeeding duration were collected at periodic study visits from participants in PREVAIL (n = 245), a birth cohort in Cincinnati, OH. Addresses were assigned a Deprivation Index score, a validated measure of SEE, and dichotomized into highest SEE (least deprived quartile of scores) and not highest SEE (remaining quartiles). Longitudinal and Poisson models assessed differences in BMIz by SEE over the second year of life and obesity risk at age two, respectively (highest SEE, reference), while attenuation of obesity risk by breastfeeding duration was tested in mediation models.

RESULTS

Residing outside of the highest SEE neighbourhoods was associated with an increased BMIz of 0.04 (95%CI 0.02, 0.06) per month of life and increased obesity risk at age two (aRR: 3.7, 95%CI 1.2, 16.2), controlling for family socio-demographics. Breastfeeding duration attenuated >9% of the obesity risk attributable to SEE (mediated RR: 3.4, 95%CI 1.1, 14.8).

DISCUSSION

In the PREVAIL Cohort, residing outside of the highest SEE neighbourhoods predicted a significant increase in BMIz and obesity risk in children before age two, a relationship that was partially mediated by breastfeeding duration.

CONCLUSION

Breastfeeding support may play an important role in reducing obesity rates in children in lower SEE neighbourhoods.

Comparison of viral inactivation methods on the characteristics of extracellular vesicles from SARS-CoV-2 infected human lung epithelial cells

The interaction of SARS-CoV-2 infection with extracellular vesicles (EVs) is of particular interest at the moment. Studying SARS-CoV-2 contaminated-EV isolates in instruments located outside of the biosafety level-3 (BSL-3) environment requires knowing how viral inactivation methods affect the structure and function of extracellular vesicles (EVs). Therefore, three common viral inactivation methods, ultraviolet-C (UVC; 1350 mJ/cm² ), β-propiolactone (BPL; 0.005%), heat (56°C, 45 min) were performed on defined EV particles and their proteins, RNAs, and function. Small EVs were isolated from the supernatant of SARS-CoV-2-infected human lung epithelial Calu-3 cells by stepwise centrifugation, ultrafiltration and qEV size-exclusion chromatography. The EV isolates contained SARS-CoV-2. UVC, BPL and heat completely abolished SARS-CoV-2 infectivity of the contaminated EVs. Particle detection by electron microscopy and nanoparticle tracking was less affected by UVC and BPL than heat treatment. Western blot analysis of EV markers was not affected by any of these three methods. UVC reduced SARS-CoV-2 spike detectability by quantitative RT-PCR and slightly altered EV-derived β-actin detection. Fibroblast migration-wound healing activity of the SARS-CoV-2 contaminated-EV isolate was only retained after UVC treatment. In conclusion, specific viral inactivation methods are compatible with specific measures in SARS-CoV-2 contaminated-EV isolates. UVC treatment seems preferable for studying functions of EVs released from SARS-CoV-2 infected cells.

Translational Proteomic Approach for Cholangiocarcinoma Biomarker Discovery, Validation, and Multiplex Assay Development: A Pilot Study

Cholangiocarcinoma (CCA) is a highly lethal disease because most patients are asymptomatic until they progress to advanced stages. Current CCA diagnosis relies on clinical imaging tests and tissue biopsy, while specific CCA biomarkers are still lacking. This study employed a translational proteomic approach for the discovery, validation, and development of a multiplex CCA biomarker assay. In the discovery phase, label-free proteomic quantitation was performed on nine pooled plasma specimens derived from nine CCA patients, nine disease controls (DC), and nine normal individuals. Seven proteins (S100A9, AACT, AFM, and TAOK3 from proteomic analysis, and NGAL, PSMA3, and AMBP from previous literature) were selected as the biomarker candidates. In the validation phase, enzyme-linked immunosorbent assays (ELISAs) were applied to measure the plasma levels of the seven candidate proteins from 63 participants: 26 CCA patients, 17 DC, and 20 normal individuals. Four proteins, S100A9, AACT, NGAL, and PSMA3, were significantly increased in the CCA group. To generate the multiplex biomarker assays, nine machine learning models were trained on the plasma dynamics of all seven candidates (All-7 panel) or the four significant markers (Sig-4 panel) from 45 of the 63 participants (70%). The best-performing models were tested on the unseen values from the remaining 18 (30%) of the 63 participants. Very strong predictive performances for CCA diagnosis were obtained from the All-7 panel using a support vector machine with linear classification (AUC = 0.96; 95% CI 0.88–1.00) and the Sig-4 panel using partial least square analysis (AUC = 0.94; 95% CI 0.82–1.00). This study supports the use of the composite plasma biomarkers measured by clinically compatible ELISAs coupled with machine learning models to identify individuals at risk of CCA. The All-7 and Sig-4 assays for CCA diagnosis should be further validated in an independent prospective blinded clinical study.

Maternal antibiotics disrupt microbiome, behavior, and temperature regulation in unexposed infant mice

Maternal antibiotic (ABx) exposure can significantly perturb the transfer of microbiota from mother to offspring, resulting in dysbiosis of potential relevance to neurodevelopmental disorders such as autism spectrum disorder (ASD). Studies in rodent models have found long-term neurobehavioral effects in offspring of ABx-treated dams, but ASD-relevant behavior during the early preweaning period has thus far been neglected. Here, we exposed C57BL/6J mouse dams to ABx (5 mg/ml neomycin, 1.25 μg/ml pimaricin, .075% v/v acetic acid) dissolved in drinking water from gestational day 12 through offspring postnatal day 14. A number of ASD-relevant behaviors were assayed in offspring, including ultrasonic vocalization (USV) production during maternal separation, group huddling in response to cold challenge, and olfactory-guided home orientation. In addition, we obtained measures of thermoregulatory competence in pups during and following behavioral testing. We found a number of behavioral differences in offspring of ABx-treated dams (e.g., modulation of USVs by pup weight, activity while huddling) and provide evidence that some of these behavioral effects can be related to thermoregulatory deficiencies, particularly at younger ages. Our results suggest not only that ABx can disrupt microbiomes, thermoregulation, and behavior, but that metabolic effects may confound the interpretation of behavioral differences observed after early-life ABx exposure.

Bifidobacterium Species Colonization in Infancy: A Global Cross-Sectional Comparison by Population History of Breastfeeding

Bifidobacterium species are beneficial and dominant members of the breastfed infant gut microbiome; however, their health benefits are partially species-dependent. Here, we characterize the species and subspecies of Bifidobacterium in breastfed infants around the world to consider the potential impact of a historic dietary shift on the disappearance of B. longum subsp. infantis in some populations. Across populations, three distinct patterns of Bifidobacterium colonization emerged: (1) The dominance of Bifidobacterium longum subspecies infantis, (2) prevalent Bifidobacterium of multiple species, and (3) the frequent absence of any Bifidobacterium. These patterns appear related to a country’s history of breastfeeding, with infants in countries with historically high rates of long-duration breastfeeding more likely to be colonized by B. longum subspecies infantis compared with infants in countries with histories of shorter-duration breastfeeding. In addition, the timing of infant colonization with B. longum subsp. infantis is consistent with horizontal transmission of this subspecies, rather than the vertical transmission previously reported for other Bifidobacterium species. These findings highlight the need to consider historical and cultural influences on the prevalence of gut commensals and the need to understand epidemiological transmission patterns of Bifidobacterium and other major commensals.

Human Milk Oligosaccharides: Potential Applications in COVID-19

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has become a global health crisis with more than four million deaths worldwide. A substantial number of COVID-19 survivors continue suffering from long-COVID syndrome, a long-term complication exhibiting chronic inflammation and gut dysbiosis. Much effort is being expended to improve therapeutic outcomes. Human milk oligosaccharides (hMOS) are non-digestible carbohydrates known to exert health benefits in breastfed infants by preventing infection, maintaining immune homeostasis and nurturing healthy gut microbiota. These beneficial effects suggest the hypothesis that hMOS might have applications in COVID-19 as receptor decoys, immunomodulators, mucosal signaling agents, and prebiotics. This review summarizes hMOS biogenesis and classification, describes the possible mechanisms of action of hMOS upon different phases of SARS-CoV-2 infection, and discusses the challenges and opportunities of hMOS research for clinical applications in COVID-19.

Breastfeeding and post-perinatal infant deaths in the United States, A national prospective cohort analysis

Background

Reducing infant mortality is a major public health goal. The potential impact of breastfeeding on infant deaths is not well studied in the United States (US).

Methods

We analyzed linked birth-death certificates for 3,230,500 US births that occurred in 2017, including 6,969 post-perinatal deaths from 7-364 days of age as the primary outcome, further specified as late-neonatal (7-27 days) or post-neonatal (28-364 days) deaths. The primary exposure was 'ever breastfed' obtained from birth certificates. Multiple logistic regression examined associations of ever breastfeeding with post-perinatal deaths and specific causes of deaths, controlling for maternal and infant factors.

Findings

We observed an adjusted reduced odds ratio (AOR)= 0·74 with 95% confidence intervals (CI)=0·70-0·79 for the association of breastfeeding initiation with overall infant deaths (7-364 days), AOR=0·60 (0·54-0·67) for late-neonatal deaths, and AOR=0·81 (0·76-0·87) for post-neonatal deaths. In race/ethnicity-stratified analysis, significant associations of breastfeeding initiation with reduced odds of overall infant deaths were observed for Hispanics [AOR=0·64 (0·55-0·74)], non-Hispanic Whites [AOR=0·75 (0·69-0·81)], non-Hispanic Blacks [AOR=0·83 (0·75-0·91)], and non-Hispanic Asians [AOR=0·51 (0·36-0·72)]. Across racial/ethnic groups, effect sizes for late-neonatal deaths were consistently larger than those for post-neonatal deaths. Significant effects of breastfeeding initiation were observed for deaths due to infection [AOR=0·81(0·69-0·94)], Sudden Unexpected Infant Death [AOR=0·85 (0·78-0·92)], and necrotizing enterocolitis [AOR=0·67 (0·49-0·90)].

Interpretation

Breastfeeding initiation is significantly associated with reduced odds of post-perinatal infant deaths in multiple racial and ethnic groups within the US population. These findings support efforts to improve breastfeeding in infant mortality reduction initiatives.

Persistence of Maternal Anti-Rotavirus Immunoglobulin G in the Post-Rotavirus Vaccine Era

To assess whether titers of anti-rotavirus immunoglobulin G persist during the post-rotavirus vaccine era, the Pediatric Respiratory and Enteric Virus Acquisition and Immunogenesis Longitudinal (PREVAIL) Cohort analyzed serum samples collected from Cincinnati-area mothers and young infants in 2017-2018. Rotavirus-specific antibodies continue to be transferred from US mothers to their offspring in the post-rotavirus vaccine era, despite dramatic decreases in childhood rotavirus gastroenteritis.

Breastfeeding Disparities and Their Mediators in an Urban Birth Cohort of Black and White Mothers

Background: Black mothers in the United States have shorter breastfeeding (BF) durations and less exclusive breastfeeding (EBF) than others. The factors underlying these disparities require investigation. Methods: Using longitudinal data from a CDC-sponsored birth cohort in Cincinnati, Ohio, we analyzed the factors mediating racial disparity in BF outcomes. Study mothers were enrolled in prenatal clinics associated with two large birth hospitals. Analysis was restricted to racial groups with sufficient numbers in the cohort, non-Hispanic Black (n = 92) and White (n = 113) mothers, followed to at least 6 months postpartum. Results: Black mothers were 25 times more likely to reside in socioeconomically deprived neighborhoods and 20 times more likely to have an annual household income <$50,000/year than White mothers (p < 0.001). The gap in EBF for 6 weeks was 45 percentage points by racial group (13%-Black mothers versus 58%-White mothers, p < 0.001); in any BF at 6 months was 37 percentage points (28%-Black mothers versus 65%-White mothers, p < 0.001); and in mothers meeting their own intention to BF at least 6 months was 51 percentage points (29%-Black mothers versus 80%-White mothers, p < 0.001). Racial disparity in EBF at 6 weeks was mediated in logistic regression models by inequities in socioeconomic position, maternal hypertension, and BF intention. Racial disparities in BF at 6 months or meeting 6-month BF intention were mediated by inequities in socioeconomic position, maternal obesity, and EBF at 6 weeks. Not all BF disparities could be explained by models used in these analyses. Conclusions: Efforts to lessen BF disparities should address the underlying structural inequities that disproportionately affect Black mothers and children, should incorporate maternal health, and focus on breastfeeding exclusivity and duration. Few Black mothers achieved EBF at 6 weeks, which contributed to disparity in BF duration. Greater attention to Black mother-infant pairs is a public health priority.

Impact of Institutional Breastfeeding Support in Very Low-Birth Weight Infants

Background and Objectives: Feeding of human milk is associated with improved health outcomes in preterm infants. Mothers of preterm infants have difficulty establishing and maintaining an adequate milk supply. Our institution participated in Best Fed Beginnings (BFB), a national breastfeeding quality improvement collaborative, in 2012. Although most practice changes targeted healthy term infants, we hypothesized that mother's milk feeding (MMF) to preterm infants would also improve. Our objective was to compare MMF in very low-birth weight (VLBW) infants at discharge before and after our participation in BFB. Materials and Methods: We completed a retrospective chart review of VLBW infants born between January 2006 and June 2016. The primary outcome measure was the percentage of VLBW infants receiving MMF at hospital discharge. We used Fisher's exact test to determine the difference before and after 2012 and performed the Kruskal-Wallis test to determine changes in median time to pump initiation in mothers of VLBW infants. Multiple logistic regression was used to determine variables associated with the primary outcome. Results: A total of 1,077 VLBW infants were eligible. After launching BFB, MMF at discharge increased in VLBW infants, from 35.2% to 46.0%, p < 0.001. Median time to pump initiation decreased from 11 to 5 hours after 2012, p = 0.0001. Factors significantly associated with receiving MMF at discharge included birth post-BFB; private insurance; non-Black race; shorter length of stay; older maternal age; and mother's milk as first feeding. Conclusions: Hospital culture supportive of breastfeeding impacts not only healthy term infants but also VLBW infants. Earlier initiation of milk expression significantly improves provision of MMF to preterm infants at discharge.

Pediatric Respiratory and Enteric Virus Acquisition and Immunogenesis in US Mothers and Children Aged 0-2: PREVAIL Cohort Study

BACKGROUND

Acute gastroenteritis (AGE) and acute respiratory infections (ARIs) cause significant pediatric morbidity and mortality. Developing childhood vaccines against major enteric and respiratory pathogens should be guided by the natural history of infection and acquired immunity. The United States currently lacks contemporary birth cohort data to guide vaccine development.

OBJECTIVE

The PREVAIL (Pediatric Respiratory and Enteric Virus Acquisition and Immunogenesis Longitudinal) Cohort study was undertaken to define the natural history of infection and immune response to major pathogens causing AGE and ARI in US children.

METHODS

Mothers in Cincinnati, Ohio, were enrolled in their third trimester of pregnancy, with intensive child follow-up to 2 years. Blood samples were obtained from children at birth (cord), 6 weeks, and 6, 12, 18, and 24 months. Whole stool specimens and midturbinate nasal swabs were collected weekly and tested by multipathogen molecular assays. Saliva, meconium, maternal blood, and milk samples were also collected. AGE (≥3 loose or watery stools or ≥1 vomiting episode within 24 hours) and ARI (cough or fever) cases were documented by weekly cell phone surveys to mothers via automated SMS text messaging and review of medical records. Immunization records were obtained from registries and providers. follow-up ended in October 2020. Pathogen-specific infections are defined by a PCR-positive sample or rise in serum antibody.

RESULTS

Of the 245 enrolled mother-child pairs, 51.8% (n=127) were White, 43.3% (n=106) Black, 55.9% (n=137) publicly insured, and 86.5% (n=212) initiated breastfeeding. Blood collection was 100.0% for mothers (n=245) and 85.7% for umbilical cord (n=210). A total of 194/245 (79.2%) mother-child pairs were compliant based on participation in at least 70% (≥71/102 study weeks) of child-weeks and providing 70% or more of weekly samples during that time, or blood samples at 18 or 24 months. Compliant participants (n=194) had 71.0% median nasal swab collection (IQR 30.0%-90.5%), with 98.5% (191/194) providing either an 18- or 24-month blood sample; median response to weekly SMS text message surveys was 95.1% (IQR 76.5%-100%). Compliant mothers reported 2.0 AGE and 4.5 ARI cases per child-year, of which 25.5% (160/627) and 38.06% (486/1277) of cases, respectively, were medically attended; 0.5% of AGE (3/627) and 0.55% of ARI (7/1277) cases were hospitalized.

CONCLUSIONS

The PREVAIL Cohort demonstrates intensive follow-up to document the natural history of enteric and respiratory infections and immunity in children 0-2 years of age in the United States and will contribute unique data to guide vaccine recommendations. Testing for pathogens and antibodies is ongoing.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/22222.

Is Blood Type Associated with COVID-19 Severity?

Blood type purportedly influences susceptibility to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, but whether it affects severity of coronavirus disease 2019 (COVID-19) is unclear. Therefore, we examined the association of blood type and rhesus with hospitalization and disease severity among 428 COVID-19 patients diagnosed at the University of Cincinnati health system. In the sample, 50.2% of participants had the blood type O, 38.7% had the blood type A, 17.5% had the blood type B, and 3.5% had the blood type AB. In analysis adjusted for sociodemographic characteristics and comorbidities, the blood types A (OR: 0.90, 95% CI: 0.54, 1.50), B (OR: 0.93, 95% CI: 0.51, 1.69), AB (OR: 0.69, 95% CI: 0.20, 2.41), and O (OR: 1.18, 95%: 0.74, 1.98) were not associated with hospitalization for COVID-19. Similarly, the blood types A (OR: 0.93, 95% CI: 0.52, 1.65), B (OR: 0.92, 95% CI: 0.46, 1.84), AB (OR: 0.30, 95% CI: 0.04, 2.44), and O (OR: 1.25, 95%: 0.73, 2.14) were not associated with admission to intensive care unit or death in COVID-19. In conclusion, blood type is not associated with hospitalization or disease severity in COVID-19; therefore, it may not be useful marker for identifying patients at risk for severe COVID-19.

Factors Associated with Hospitalization and Disease Severity in a Racially and Ethnically Diverse Population of COVID-19 Patients

BACKGROUND

The coronavirus disease (COVID-19) first identified in Wuhan in December 2019 became a pandemic within a few months of its discovery. The impact of COVID-19 is due to both its rapid spread and its severity, but the determinants of severity have not been fully delineated.

OBJECTIVE

Identify factors associated with hospitalization and disease severity in a racially and ethnically diverse cohort of COVID-19 patients.

METHODS

We analyzed data from COVID-19 patients diagnosed at the University of Cincinnati health system from March 13, 2020 to May 31, 2020. Severe COVID-19 was defined as admission to intensive care unit or death. Logistic regression modeling adjusted for covariates was used to identify the factors associated with hospitalization and severe COVID-19.

RESULTS

Among the 689 COVID-19 patients included in our study, 29.2% were non-Hispanic White, 25.5% were non-Hispanic Black, 32.5% were Hispanic, and 12.8% were of other race/ethnicity. About 31.3% of patients were hospitalized and 13.2% had severe disease. In adjusted analyses, the sociodemographic factors associated with hospitalization and/or disease severity included older age, non-Hispanic Black or Hispanic race/ethnicity (compared to non-Hispanic White), and smoking. The following comorbidities: diabetes, hypercholesterolemia, asthma, COPD, chronic kidney disease, cardiovascular diseases, osteoarthritis, and vitamin D deficiency were associated with hospitalization and/or disease severity. Hematological disorders such as anemia, coagulation disorders, and thrombocytopenia were associated with both hospitalization and disease severity.

CONCLUSION

This study confirms race and ethnicity as predictors of severe COVID-19. It also finds clinical risk factors for hospitalization and severe COVID-19 not previously identified such a vitamin D deficiency, hypercholesterolemia, osteoarthritis, and anemia.

Rotavirus Vaccine Take in Infants Is Associated With Secretor Status

Rotaviruses bind to enterocytes in a genotype-specific manner via histo-blood group antigens (HBGAs), which are also detectable in saliva. We evaluated antirotavirus immunoglobulin A seroconversion ('vaccine take") among 166 Ghanaian infants after 2-3 doses of G1P[8] rotavirus vaccine during a vaccine trial, by HBGA status from saliva collected at age 4.1 years. Only secretor status was associated with seroconversion: 41% seroconversion for secretors vs 13% for nonsecretors; relative risk, 3.2 (95% confidence interval, 1.2-8.1; P = .016). Neither Lewis antigen nor salivary antigen blood type was associated with seroconversion. Likelihood of "take" for any particular rotavirus vaccine may differ across populations based on HBGAs.

2633. Influenza and Tdap Vaccination Coverage among Pregnant Women in the PREVAIL Cohort

Background

The ACIP recommends influenza and Tdap vaccination during pregnancy to reduce the risk of influenza and pertussis in the mother and her infant. We assessed influenza and Tdap vaccination coverage and associated factors among pregnant women enrolled in PREVAIL, a prospective birth cohort study in Cincinnati, OH. We assessed sensitivity and specificity of self report for both vaccines against state registry, maternal healthcare provider, and work-place records.

Methods

We enrolled and interviewed 265 pregnant women regarding self-reported receipt of influenza and Tdap vaccines, and obtained vaccine records from registry, electronic medical record, provider, employer, or pharmacy. We grouped subjects by documented vaccination status and analyzed demographic variables and vaccine attitudes regarding efficacy, safety, and hesitancy using unadjusted Fisher exact tests. We analyzed sensitivity and specificity of maternal recall.

Results

We identified documentation of influenza and Tdap vaccine receipt during pregnancy in 172/265 (64.9%) and 238/265 (89.8%) of women, respectively (Figure 1); by self report, 177/265 (66.8%) reported receiving influenza and 221/265 (83.4%) Tdap vaccine. The two most common primary reasons cited for receiving influenza vaccine were “to protect my baby” (36.7%) and “to protect myself” (26%; Figure 2). Pregnant women were more likely to get Tdap vaccine if a healthcare worker recommended it (OR 5.4). Subjects were more likely to get influenza vaccine if they believed it was effective in preventing influenza in themselves (OR 9.0) or their babies (OR 8.1). While positive recall had a high concordance (95.2% and 93.4% for influenza and Tdap, respectively), 12.5% and 32.1% of mothers incorrectly recalled not receiving an influenza or Tdap vaccine, respectively, that was documented as received in the records (Figure 3).

Conclusion

We found high concordance between maternal recall and verification for both influenza and Tdap vaccines. In this single-site cohort of 265 women, self report was a reliable measure of vaccination status among pregnant women. Provider communication to pregnant women regarding effectiveness of influenza and Tdap vaccinations for themselves and their infants may lead to higher maternal vaccination rates.

Disclosures

All authors: No reported disclosures.

Associations Between Breastfeeding Initiation and Infant Mortality in an Urban Population

Background: Breastfeeding promotion and support are not universally accepted in the United States as a strategy to reduce infant mortality. We investigated associations between breastfeeding and infant mortality in an urban population with high infant mortality and low breastfeeding rates. Methods: A retrospective epidemiologic study linked birth-infant death data for 148,679 live births in Shelby County, Tennessee from January 2004 to December 2014. Births <500 g, deaths ≤7 days, deaths because of congenital anomalies or malignant neoplasms, and records with missing breastfeeding status were excluded. Main outcomes were infant death before the first birthday, neonatal death <28 days, and postneonatal death ≥28 days by ever or never breastfed. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for breastfeeding initiation were adjusted for maternal factors and infant factors. Results: Initiation of breastfeeding was associated with a significant reduction in total infant mortality (OR = 0.81, 95% CI = 0.68-0.97, p = 0.023). Neonatal mortality was also significantly reduced with any breastfeeding (OR = 0.49, 95% CI = 0.34-0.72, p = 0.001). Postneonatal mortality was not significantly associated with breastfeeding initiation in the overall population (OR = 0.95, 95% CI = 0.78-1.17, p = 0.65), but was significant in the nonblack population (OR = 0.63, 95% CI = 0.41-0.98, p = 0.039). An association was observed between breastfeeding initiation and infant mortality from infectious disease (OR = 0.49, 95% CI = 0.32-0.77, p = 0.002). Conclusions: In an urban area with high infant mortality and low breastfeeding rates, initiation of breastfeeding was significantly associated with reductions in overall infant mortality, neonatal mortality, and infection-related deaths. Breastfeeding promotion, protection, and support should be an integral strategy of infant mortality reduction initiatives.

A Randomized Trial of Maternal Docosahexaenoic Acid Supplementation to Reduce Inflammation in Extremely Preterm Infants

Maternal supplementation with 1000 mg/day docosahexaenoic acid (DHA) provides third trimester DHA accretion levels in breast milk for the preterm infant. We hypothesized that DHA supplementation to mothers providing breastmilk for extremely preterm infants would result in decreased inflammatory markers, in the infant. Mother/infant dyads (n = 27) were enrolled at birth and mothers were assigned to receive 200 or 1000 mg/day of DHA. Milk and plasma samples were analyzed for fatty acids and inflammatory markers. Decreases in inflammation were observed in both maternal and infant plasma and correlated with red blood cell (RBC) DHA levels. The fact that maternal DHA supplementation decreases infant markers of inflammation implies that DHA, delivered through breastmilk, has the potential to decrease inflammation in the infant.

NIH workshop on human milk composition: summary and visions

Nationally representative data from mother-child dyads that capture human milk composition (HMC) and associated health outcomes are important for advancing the evidence to inform federal nutrition and related health programs, policies, and consumer information across the governments in the United States and Canada as well as in nongovernment sectors. In response to identified gaps in knowledge, the National Institute of Diabetes and Digestive and Kidney Diseases of the NIH sponsored the "Workshop on Human Milk Composition-Biological, Environmental, Nutritional, and Methodological Considerations" held 16-17 November 2017 in Bethesda, Maryland. Through presentations and discussions, the workshop aimed to 1) share knowledge on the scientific need for data on HMC; 2) explore the current understanding of factors affecting HMC; 3) identify methodological challenges in human milk (HM) collection, storage, and analysis; and 4) develop a vision for a research program to develop an HMC data repository and database. The 4 workshop sessions included 1) perspectives from both federal agencies and nonfederal academic experts, articulating scientific needs for data on HMC that could lead to new research findings and programmatic advances to support public health; 2) information about the factors that influence lactation and/or HMC; 3) considerations for data quality, including addressing sampling strategies and the complexities in standardizing collection, storage, and analyses of HM; and 4) insights on how existing research programs and databases can inform potential visions for HMC initiatives. The general consensus from the workshop is that the limited scope of HM research initiatives has led to a lack of robust estimates of the composition and volume of HM consumed and, consequently, missed opportunities to improve maternal and infant health.

A Pilot Study of Human Milk to Reduce Intestinal Inflammation After Bone Marrow Transplant

OBJECTIVE

Human milk administration in the early peritransplant period would lower intestinal inflammation after bone marrow transplant (BMT).

MATERIALS AND METHODS

Children 0-5 years undergoing BMT received either a ready-to-feed human milk preparation designed for these children (Prolacta Bioscience, Duarte, CA) or standard formula. Babies breastfeeding at the time of BMT were also enrolled on the human milk arm. Human milk was administered from day -3 until day +14 after BMT. Metagenomic shotgun sequencing and metabolomics of stool, plasma cytokines, and regenerating islet-derived 3α (REG3α) levels were measured at enrollment and day +14. Human leukocyte antigen-DR isotype (HLA-DR), CD38, and CD69 expression on T cells were evaluated at day +21.

RESULTS

Forty-six children were enrolled, 32 received human milk (donor milk n = 23, breastfeeding babies n = 9), and 14 were controls who received standard feeds supervised by a BMT dietician. Twenty-four patients received at least 60% of goal human milk and were evaluable. Plasma interleukin (IL)-8 (p = 0.04), IL-10 (p = 0.02), and REG3α (p = 0.03) were decreased in the human milk cohort. Peripheral blood CD69⁺ CD8⁺ T cells were higher in controls (p = 0.01). Species abundance of Adenovirus (p = 0.00034), Escherichia coli (p = 0.0017), Cryptosporidium parvum (p = 0.0006), Dialister invisus (p = 0.01), and Pseudomonas aeruginosa (p = 0.05) from stool was higher in controls. Stool alanine, tyrosine, methionine, and the ratio of fecal alanine to choline and phosphocholine were higher in controls (p < 0.05). No difference was observed in stool propionate and butyrate levels as measures of short-chain fatty acids between the two cohorts.

CONCLUSIONS

Administration of human milk resulted in decreased markers of intestinal inflammation and could be a valuable adjunct for patients after BMT.

Fatty Acids and Fat-Soluble Vitamins in Breast Milk: Physiological Significance and Factors Affecting Their Concentrations

Fatty acids (FAs) and fat-soluble vitamins are vital components of the human milk lipid fraction. About two-thirds of the human milk FA fraction consist of oleic, linoleic, and palmitic FAs, but the precise composition depends on maternal geography, diet, and genetics. Mothers with high fish consumption have more docosahexaenoic acid (DHA) and other ω-3 FAs in their milk, while mothers with high dairy consumption have more branched-chain FAs in their milk. Vitamins A and E are the most common fat-soluble vitamins, but milk concentrations vary, depending on maternal diet and body stores. Vitamin D is typically low or undetectable in mother's milk and typically fails to meet the infant needs. However, trial data indicate that high maternal supplementation (6,400 IU/day) safely provides nutritionally adequate amounts of vitamin D in her milk. FA and fat-soluble vitamin levels in mother's milk can significantly influence infant health; for example, in preterm infants, low endogenous stores of DHA paired with low levels in maternal milk may influence the risk of chronic lung disease and other inflammatory conditions. Greater attention is warranted to the variation in FA and fat-soluble vitamin content of human milk in relation to infant health.

The Impact of Maternal Antibiotics on Neonatal Disease

OBJECTIVES

We examined the impact of prenatal exposure to maternal antibiotics on risk of necrotizing enterocolitis (NEC), late onset sepsis (LOS), and death in infants born preterm.

STUDY DESIGN

Secondary data analysis was conducted via an extant cohort of 580 infants born <32 weeks of gestation and enrolled in 3 level III neonatal intensive care units. Prenatal antibiotic exposure was defined as antibiotics received by the mother within 72 hours before delivery. Postnatal empiric antibiotic exposure was defined as antibiotic initiated within the first day of life without documented infection, categorized as low (<5 days) or high (>5 days) duration.

RESULTS

Two-thirds of mothers received antibiotics within 72 hours before delivery, of whom 59.8% received >1 antibiotic. Ampicillin (37.6%) and azithromycin (26.4%) were the most common antibiotics given. NEC occurred in 7.5%, LOS in 11.1%, death in 9.6%, and the combined outcome of NEC, LOS, or death in 21.3% of study infants. In multiple logistic regression models adjusted for gestational age, postnatal empiric antibiotic exposure, and other factors, prenatal antibiotic exposure was associated with reduced risk of NEC (OR 0.28; 95% CI 0.14-0.56; P < .001), death (OR 0.29; 95% CI 0.14-0.60; P = .001), but not LOS (OR 1.59; 95% CI 0.84-2.99; P = .15), although protection was significant for the combined outcome (OR 0.52, P < .001). High postnatal empiric antibiotic exposure was associated with greater risk of death but not other outcomes in multiple regression models (OR 3.18, P = .002).

CONCLUSIONS

Prenatal antibiotic exposure was associated with lower rates of NEC or death of infants born preterm, and its impact on infant outcomes warrants further study.

Nutrition Support Team Guide to Maternal Diet for the Human-Milk-Fed Infant

BACKGROUND

Human milk feeding is encouraged for all infants; however, the mammary gland depends on maternal dietary intake of vitamins A, B1, B2, B6, B12, D, docosahexaenoic acid (DHA), choline, and iodine. Nutrition support team knowledge of maternal feeding guidelines for these nutrient sources can therefore impact infant intake. We hypothesized that these key nutrients for lactation in the mother's diet would be less than the dietary guidelines in the United States.

METHODS

This was a secondary analysis of nutrition data collected during a randomized, controlled trial. Dietary records were analyzed from 16 mothers (13 with singleton and 3 with multiple births) completing the study. Mean dietary intakes of selected nutrients were calculated and compared with the current dietary reference intakes.

RESULTS

Mean maternal dietary intake for singletons was significantly (P < .05) lower than the dietary reference intakes for (vitamin A (58%), vitamin D (44%), and choline (58%);) DHA comprised only 5% of the current expert recommendation. Based on singleton recommendations, mothers to twins consumed an adequate intake except for DHA.

CONCLUSIONS

Women providing breast milk for singleton preterm infants did not consume dietary reference intakes for key nutrients. Twin mothers' diets were adequate except for DHA, but these guidelines are based on singleton pregnancies and remain poorly understood for twin needs. The nutrition support team can have a unique role in maternal dietary education to impact human milk nutrient delivery to the infant.

Markers of Oxidative Stress in Human Milk do not Differ by Maternal BMI But are Related to Infant Growth Trajectories

Objective Obesity in adults is associated with inflammation and oxidative stress. Whether or not this phenotype is reflected in human milk (HM) composition, or may impact infant growth remains unknown. We investigated whether HM from overweight/obese (OW/Ob) mothers exhibited higher concentrations of inflammatory cytokines and markers of oxidative stress. We also correlated these bioactive components with infant growth patterns. Methods This was an observational cohort of 56 breastfeeding mothers and their infants [33 normal weight (NW) and 23 OW/Ob]. Infants were followed until 6 months of age and HM collected at 2-weeks and 4-months. Results Markers of oxidative stress, 8-hydroxy-deoxyguanosine (8OHdG) and 4-hydroxynonenol (HNE), decreased in HM over time (p < 0.001) and did not differ between NW and OW/Ob women. Concentrations of inflammatory cytokines, IL-6, IL-8, and TNF-α, were all inter-correlated (p < 0.001) but did not differ between NW and OW/Ob women. HM fat, protein, lactose, and total calories did not differ between NW and OW/Ob women. Infant growth patterns did not differ by group. In a model of infant weight-for-length-Z score trajectory, there was a significant interaction between both lactose and 8OHdG with maternal group: HM lactose and 8OHdG concentrations were both positively associated with increases in WLZ trajectory only among infants breastfed by OW/Ob mothers. Conclusions for Practice HM composition was relatively stable between NW and OW/Ob women. In exclusively breastfed infants, HM concentrations of lactose and 8OHdG, a marker of oxidative stress, may contribute to regulation of infant weight gain, especially among infants of OW/Ob women.

Secretor and Salivary ABO Blood Group Antigen Status Predict Rotavirus Vaccine Take in Infants

Histo-blood group antigens (HBGAs) expressed on enterocytes are proposed receptors for rotaviruses and can be measured in saliva. Among 181 Pakistani infants in a G1P[8] rotavirus vaccine trial who were seronegative at baseline, anti-rotavirus immunoglobulin A seroconversion rates after 3 vaccine doses differed significantly by salivary HBGA phenotype, with the lowest rate (19%) among infants who were nonsecretors (ie, who did not express the carbohydrate synthesized by FUT2), an intermediate rate (30%) among secretors with non-blood group O, and the highest rate (51%) among secretors with O blood group. Differences in HBGA expression may be responsible for some of the discrepancy in the level of protection detected for the current rotavirus vaccines in low-income versus high-income settings.

Lactational Stage of Pasteurized Human Donor Milk Contributes to Nutrient Limitations for Infants

BACKGROUND

Mother's own milk is the first choice for feeding preterm infants, but when not available, pasteurized human donor milk (PDM) is often used. Infants fed PDM have difficulties maintaining appropriate growth velocities. To assess the most basic elements of nutrition, we tested the hypotheses that fatty acid and amino acid composition of PDM is highly variable and standard pooling practices attenuate variability; however, total nutrients may be limiting without supplementation due to late lactational stage of the milk.

METHODS

A prospective cross-sectional sampling of milk was obtained from five donor milk banks located in Ohio, Michigan, Colorado, Texas-Ft Worth, and California. Milk samples were collected after Institutional Review Board (#07-0035) approval and informed consent. Fatty acid and amino acid contents were measured in milk from individual donors and donor pools (pooled per Human Milk Banking Association of North America guidelines). Statistical comparisons were performed using Kruskal-Wallis, Spearman's, or Multivariate Regression analyses with center as the fixed factor and lactational stage as co-variate.

RESULTS

Ten of the fourteen fatty acids and seventeen of the nineteen amino acids analyzed differed across Banks in the individual milk samples. Pooling minimized these differences in amino acid and fatty acid contents. Concentrations of lysine and docosahexaenoic acid (DHA) were not different across Banks, but concentrations were low compared to recommended levels.

CONCLUSIONS

Individual donor milk fatty acid and amino acid contents are highly variable. Standardized pooling practice reduces this variability. Lysine and DHA concentrations were consistently low across geographic regions in North America due to lactational stage of the milk, and thus not adequately addressed by pooling. Targeted supplementation is needed to optimize PDM, especially for the preterm or volume restricted infant.

Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis

BACKGROUND

Necrotizing enterocolitis (NEC) is a catastrophic disease of preterm infants, and microbial dysbiosis has been implicated in its pathogenesis. Studies evaluating the microbiome in NEC and preterm infants lack power and have reported inconsistent results.

METHODS AND RESULTS

Our objectives were to perform a systematic review and meta-analyses of stool microbiome profiles in preterm infants to discern and describe microbial dysbiosis prior to the onset of NEC and to explore heterogeneity among studies. We searched MEDLINE, PubMed, CINAHL, and conference abstracts from the proceedings of Pediatric Academic Societies and reference lists of relevant identified articles in April 2016. Studies comparing the intestinal microbiome in preterm infants who developed NEC to those of controls, using culture-independent molecular techniques and reported α and β-diversity metrics, and microbial profiles were included. In addition, 16S ribosomal ribonucleic acid (rRNA) sequence data with clinical meta-data were requested from the authors of included studies or searched in public data repositories. We reprocessed the 16S rRNA sequence data through a uniform analysis pipeline, which were then synthesized by meta-analysis. We included 14 studies in this review, and data from eight studies were available for quantitative synthesis (106 NEC cases, 278 controls, 2944 samples). The age of NEC onset was at a mean ± SD of 30.1 ± 2.4 weeks post-conception (n = 61). Fecal microbiome from preterm infants with NEC had increased relative abundances of Proteobacteria and decreased relative abundances of Firmicutes and Bacteroidetes prior to NEC onset. Alpha- or beta-diversity indices in preterm infants with NEC were not consistently different from controls, but we found differences in taxonomic profiles related to antibiotic exposure, formula feeding, and mode of delivery. Exploring heterogeneity revealed differences in microbial profiles by study and the target region of the 16S rRNA gene (V1-V3 or V3-V5).

CONCLUSIONS

Microbial dysbiosis preceding NEC in preterm infants is characterized by increased relative abundances of Proteobacteria and decreased relative abundances of Firmicutes and Bacteroidetes. Microbiome optimization may provide a novel strategy for preventing NEC.

Branched-chain fatty acid composition of human milk and the impact of maternal diet: the Global Exploration of Human Milk (GEHM) Study

BACKGROUND

An understudied component of the diet, branched-chain fatty acids (BCFAs) are distinctive saturated fatty acids that may have an important influence on health. Human-milk fatty acid composition is known to differ worldwide, but comparative data are lacking on BCFAs.

OBJECTIVE

We tested the hypotheses that concentrations of BCFAs in human milk differ between populations and are associated with maternal diet.

DESIGN

We surveyed the BCFA composition of samples collected as part of a standardized, prospective study of human-milk composition. Mothers were enrolled from 3 urban populations with differing diets: Cincinnati, Ohio; Shanghai, China; and Mexico City, Mexico. Enrollment was limited to healthy mothers of term singleton infants. We undertook a cross-sectional analysis of milk from all women with samples at postpartum week 4 (n = 359; ∼120 women/site). Fatty acids were extracted from milk by using a modified Bligh-Dyer technique and analyzed by gas chromatography. Statistical analysis was performed by ANOVA and Tobit regression. For Cincinnati mothers, 24-h diet recalls were analyzed in relation to the individual BCFA concentrations measured in milk samples.

RESULTS

Total BCFAs in milk differed by site, with the highest concentration in Cincinnati followed by Mexico City and Shanghai (mean ± SE: 7.90 ± 0.41, 6.10 ± 0.36, and 4.27 ± 0.25 mg/100 mL, respectively; P < 0.001). Site differences persisted after delivery mode, maternal age, and body mass index were controlled for. The individual concentrations of iso-14:0, iso-16:0, iso-18:0, anteiso-15:0, and anteiso-17:0 also differed between sites. Milk concentrations of iso-14:0 and anteiso-15:0 were associated with maternal intake of dairy; iso-16:0 was associated with maternal intakes of dairy and beef.

CONCLUSIONS

BCFA concentrations in milk at 4 wk postpartum differed between mothers from Cincinnati, Shanghai, and Mexico City. Variations in human-milk BCFAs are influenced by diet. The impact of BCFAs on infant health warrants investigation.

Association of Chorioamnionitis with Aberrant Neonatal Gut Colonization and Adverse Clinical Outcomes

Objective

Chorioamnionitis (inflammation of the placenta and fetal membranes) and abnormal gastrointestinal colonization have been associated with an increased risk of sepsis and death in preterm infants, but whether chorioamnionitis causes abnormal pioneering gastrointestinal colonization in infants is not known. We determined the relationship between chorioamnionitis, altered infant fecal microbiome indicating abnormal gastrointestinal colonization, and adverse outcomes.

Study Design

Preterm infants ≤ 28 weeks at birth were enrolled from 3 level III NICUs in Cincinnati, Ohio and Birmingham, Alabama. Sequencing for 16S microbial gene was performed on stool samples in the first 3 weeks of life. Chorioamnionitis was diagnosed by placental histology. Late onset sepsis and death outcomes were analyzed in relation to fecal microbiota and chorioamnionitis with or without funisitis (inflammation of the umbilical cord).

Results

Of the 106 enrolled infants, 48 infants had no chorioamnionitis, 32 infants had chorioamnionitis but no funisitis (AC), and 26 infants had chorioamnionitis with funisitis (ACF). The fecal samples from ACF infants collected by day of life 7 had higher relative abundance of family Mycoplasmataceae (phylum Tenericutes), genus Prevotella (phylum Bacteroidetes) and genus Sneathia (phylum Fusobacteria). Further, AC and ACF infants had higher incidence of late-onset sepsis/death as a combined outcome. Presence of specific clades in fecal samples, specifically, order Fusobacteria, genus Sneathia or family Mycoplasmataceae, were significantly associated with higher risk of sepsis or death.

Conclusion

The results support the hypothesis that specific alterations in the pioneering infant gastrointestinal microbiota induced by chorioamnionitis predispose to neonatal sepsis or death.

Fecal Polyomavirus Excretion in Infancy

Qualitative polymerase chain reaction (PCR) was used to determine the prevalence of fecal excretion of BK virus, JC virus, and simian virus 40 in 1-year-old infants. Overall, 17.8% of 321 specimens from 64.1% of 39 infants were polyomavirus positive. These data suggest that the gastrointestinal tract may be a site of polyomavirus persistence in humans.

Role of interleukin-10 (IL-10) in regulation of GABAergic transmission and acute response to ethanol

Mounting evidence indicates that ethanol (EtOH) exposure activates neuroimmune signaling. Alterations in pro-inflammatory cytokines after acute and chronic EtOH exposure have been heavily investigated. In contrast, little is known about the regulation of neurotransmission and/or modulation by anti-inflammatory cytokines in the brain after an acute EtOH exposure. Recent evidence suggests that interleukin-10 (IL-10), an anti-inflammatory cytokine, is upregulated during withdrawal from chronic EtOH exposure. In the present study, we show that IL-10 is increased early (1 h) after a single intoxicating dose of EtOH (5 g/kg, intragastric) in Sprague Dawley rats. We also show that IL-10 rapidly regulates GABAergic transmission in dentate gyrus neurons. In brain slice recordings, IL-10 application dose-dependently decreases miniature inhibitory postsynaptic current (mIPSC) area and frequency, and decreases the magnitude of the picrotoxin sensitive tonic current (Itonic), indicating both pre- and postsynaptic mechanisms. A PI3K inhibitor LY294002 (but not the negative control LY303511) ablated the inhibitory effects of IL-10 on mIPSC area and Itonic, but not on mIPSC frequency, indicating the involvement of PI3K in postsynaptic effects of IL-10 on GABAergic transmission. Lastly, we also identify a novel neurobehavioral regulation of EtOH sensitivity by IL-10, whereby IL-10 attenuates acute EtOH-induced hypnosis. These results suggest that EtOH causes an early release of IL-10 in the brain, which may contribute to neuronal hyperexcitability as well as disturbed sleep seen after binge exposure to EtOH. These results also identify IL-10 signaling as a potential therapeutic target in alcohol-use disorders and other CNS disorders where GABAergic transmission is altered.

Metagenomic Sequencing with Strain-Level Resolution Implicates Uropathogenic E. coli in Necrotizing Enterocolitis and Mortality in Preterm Infants

Necrotizing enterocolitis (NEC) afflicts approximately 10% of extremely preterm infants with high fatality. Inappropriate bacterial colonization with Enterobacteriaceae is implicated, but no specific pathogen has been identified. We identify uropathogenic E. coli (UPEC) colonization as a significant risk factor for the development of NEC and subsequent mortality. We describe a large-scale deep shotgun metagenomic sequence analysis of the early intestinal microbiome of 144 preterm and 22 term infants. Using a pan-genomic approach to functionally subtype the E. coli, we identify genes associated with NEC and mortality that indicate colonization by UPEC. Metagenomic multilocus sequence typing analysis further defined NEC-associated strains as sequence types often associated with urinary tract infections, including ST69, ST73, ST95, ST127, ST131, and ST144. Although other factors associated with prematurity may also contribute, this report suggests a link between UPEC and NEC and indicates that further attention to these sequence types as potential causal agents is needed.

The human milk oligosaccharide 2'-fucosyllactose augments the adaptive response to extensive intestinal

Intestinal resection resulting in short bowel syndrome (SBS) carries a heavy burden of long-term morbidity, mortality, and cost of care, which can be attenuated with strategies that improve intestinal adaptation. SBS infants fed human milk, compared with formula, have more rapid intestinal adaptation. We tested the hypothesis that the major noncaloric human milk oligosaccharide 2'-fucosyllactose (2'-FL) contributes to the adaptive response after intestinal resection. Using a previously described murine model of intestinal adaptation, we demonstrated increased weight gain from 21 to 56 days (P < 0.001) and crypt depth at 56 days (P < 0.0095) with 2'-FL supplementation after ileocecal resection. Furthermore, 2'-FL increased small bowel luminal content microbial alpha diversity following resection (P < 0.005) and stimulated a bloom in organisms of the genus Parabacteroides (log2-fold = 4.1, P = 0.035). Finally, transcriptional analysis of the intestine revealed enriched ontologies and pathways related to antimicrobial peptides, metabolism, and energy processing. We conclude that 2'-FL supplementation following ileocecal resection increases weight gain, energy availability through microbial community modulation, and histological changes consistent with improved adaptation.