Lessons from mother: Long-term impact of antibodies in breast milk on the gut microbiota and intestinal immune system of breastfed offspring

Role of maternal milk in providing a healthy intestinal microbiome for the preterm neonate

The immature gastrointestinal tract of preterm neonates leads to a delayed and distinctive establishment of the gut microbiome, making them susceptible to potentially pathogenic bacteria and increasing the risk of infections. Maternal milk, recognized as the optimal source of nutrition, plays a multifaceted role in modulating the gut microbiome of premature newborns. Human milk oligosaccharides, acting as prebiotics, provide essential nourishment for key bacteria such as Bifidobacterium, contributing to the proliferation of beneficial bacterial populations. Additionally, maternal milk is rich in Immunoglobulins that stimulate immune cell responses, providing protective effects on the infant's gut mucosa. Moreover, bioactive proteins such as secretory immunoglobulin A (SIgA), lactoferrin, lysozyme, and mucins play a crucial role in defending against pathogens and regulating the immune system at the cellular level. These proteins contribute not only to infection prevention but also emphasize the impact of breast milk in fortifying the body's innate defenses. This multifaceted role of maternal milk, including essential nutrients, beneficial bacteria, and bioactive proteins, highlights the importance of promoting the mother's own milk feeding in the Neonatal Intensive Care Unit (NICU). It not only optimizes the long-term outcomes and well-being of preterm infants but also provides a holistic approach to their health and development. IMPACT: This article contributes to the current understanding of the relationship between breastfeeding and the intestinal microbiota. Fill gaps in existing literature about the subject. Provides new insights for future research.

Breastfeeding Beyond Six Months: Evidence of Child Health Benefits

Breastfeeding is globally recognized as the optimal method of infant nutrition, offering health benefits for both the child and the mother, making it a public health priority. However, the potential advantages of breastfeeding extend well beyond initial months. Breast milk adapts to the evolving needs of the growing infant, and its immunological, microbiological, and biochemical properties have been associated with enhanced protection against infections and chronic diseases, improved growth and development, and lower rates of hospitalization and mortality. This review explores the evidence supporting the continuation of breastfeeding beyond six months. More meticulous studies employing consistent methodologies and addressing confounders are essential. This will enable a more accurate determination of the extent and mechanisms of the positive impact of prolonged breastfeeding and allow for the implementation of effective public health strategies.

Antibiotics, passive smoking, high socioeconomic status and sweetened foods contribute to the risk of paediatric inflammatory bowel disease: A systematic review with meta-analysis

OBJECTIVE

Genetic and environmental factors influence pathogenesis and rising incidence of paediatric inflammatory bowel disease (PIBD). The aim was to meta-analyse evidence of diet and environmental factors in PIBD.

METHODS

A systematic search was conducted to identify diet and environmental factors with comparable risk outcome measures and had been reported in two or more PIBD studies for inclusion in meta-analyses. Those with ≥2 PIBD risk estimates were combined to provide pooled risk estimates.

RESULTS

Of 4763 studies identified, 36 studies were included. PIBD was associated with higher risk with exposure to ≥/=4 antibiotic courses (includes prescriptions/purchases/courses), passive smoking, not being breastfed, sugary drink intake, being a non-Caucasian child living in a high-income country and infection history (odds ratio [OR] range: 2-3.8). Paediatric Crohn's disease (CD) was associated with higher risk with exposure to antibiotics during early childhood, ≥/=4 antibiotic courses, high socioeconomic status (SES), maternal smoking, history of atopic conditions and infection history (OR range: 1.6-4.4). A history of infection was also associated with higher risk of paediatric ulcerative colitis (UC) (OR: 3.73). Having a higher number of siblings (≥2) was associated with lower risk of paediatric CD (OR: 0.6) and paediatric UC (OR: 0.7). Pet exposure was associated with lower risk of paediatric UC (OR: 0.5).

CONCLUSION

Several factors associated with PIBD risk were identified that could potentially be used to develop a disease screening tool. Future research is needed to address risk reduction in PIBD.

Maternal transmission as a microbial symbiont sieve, and the absence of lactation in male mammals

Gut microbiomes of mammals carry a complex symbiotic assemblage of microorganisms. Feeding newborn infants milk from the mammary gland allows vertical transmission of the parental milk microbiome to the offspring's gut microbiome. This has benefits, but also has hazards for the host population. Using mathematical models, we demonstrate that biparental vertical transmission enables deleterious microbial elements to invade host populations. In contrast, uniparental vertical transmission acts as a sieve, preventing these invasions. Moreover, we show that deleterious symbionts generate selection on host modifier genes that keep uniparental transmission in place. Since microbial transmission occurs during birth in placental mammals, subsequent transmission of the milk microbiome needs to be maternal to avoid the spread of deleterious elements. This paper therefore argues that viviparity and the hazards from biparental transmission of the milk microbiome, together generate selection against male lactation in placental mammals.

Maternal exercise preserves offspring cardiovascular health via oxidative regulation of the ryanodine receptor

OBJECTIVE

The intrauterine environment during pregnancy is a critical factor in the development of obesity, diabetes, and cardiovascular disease in offspring. Maternal exercise prevents the detrimental effects of a maternal high fat diet on the metabolic health in adult offspring, but the effects of maternal exercise on offspring cardiovascular health have not been thoroughly investigated.

METHODS

To determine the effects of maternal exercise on offspring cardiovascular health, female mice were fed a chow (C; 21% kcal from fat) or high-fat (H; 60% kcal from fat) diet and further subdivided into sedentary (CS, HS) or wheel exercised (CW, HW) prior to pregnancy and throughout gestation. Offspring were maintained in a sedentary state and chow-fed throughout 52 weeks of age and subjected to serial echocardiography and cardiomyocyte isolation for functional and mechanistic studies.

RESULTS

High-fat fed sedentary dams (HS) produced female offspring with reduced ejection fraction (EF) compared to offspring from chow-fed dams (CS), but EF was preserved in offspring from high-fat fed exercised dams (HW) throughout 52 weeks of age. Cardiomyocytes from HW female offspring had increased kinetics, calcium cycling, and respiration compared to CS and HS offspring. HS offspring had increased oxidation of the RyR2 in cardiomyocytes coupled with increased baseline sarcomere length, resulting in RyR2 overactivity, which was negated in female HW offspring.

CONCLUSIONS

These data suggest a role for maternal exercise to protect against the detrimental effects of a maternal high-fat diet on female offspring cardiac health. Maternal exercise improved female offspring cardiomyocyte contraction, calcium cycling, respiration, RyR2 oxidation, and RyR2 activity. These data present an important, translatable role for maternal exercise to preserve cardiac health of female offspring and provide insight on mechanisms to prevent the transmission of cardiovascular diseases to subsequent generations.

Microbiome: Mammalian milk microbiomes: sources of diversity, potential functions, and future research directions

Abstract

Milk is an ancient, fundamental mammalian adaptation that provides nutrition and biochemical communication to offspring. Microbiomes have been detected in milk of all species studied to date. In this review, we discuss: (a) routes by which microbes may enter milk; (b) evidence for proposed milk microbiome adaptive functions; (c) variation in milk microbiomes across mammals; and (d) future research directions, including suggestions for how to address outstanding questions on the viability and functionality of milk microbiomes. Milk microbes may be sourced from the maternal gastrointestinal tract, oral, skin, and mammary gland microbiomes and from neonatal oral and skin microbiomes. Given the variety of microbial sources, stochastic processes strongly influence milk microbiome assembly, but milk microbiomes appear to be influenced by maternal evolutionary history, diet, environment, and milk nutrients. Milk microbes have been proposed to colonize the neonatal intestinal tract and produce gene and metabolic products that influence physiology, metabolism, and immune system development. Limited epidemiological data indicate that early-life exposure to milk microbes can result in positive, long-term health outcomes. Milk microbiomes can be modified by dietary changes including providing the mother with probiotics and prebiotics. Milk replacers (i.e. infant formula) may benefit from supplementation with probiotics and prebiotics, but data are lacking on probiotics' usefulness, and supplementation should be evidence based. Overall, milk microbiome literature outside of human and model systems is scarce. We highlight the need for mechanistic studies in model species paired with comparative studies across mammals to further our understanding of mammalian milk microbiome evolution. A broader study of milk microbiomes has the potential to inform animal care with relevance to ex situ endangered species.

Lay summary

Milk is an ancient adaptation that supports the growth and development of mammalian neonates and infants. Beyond its fundamental nutritional function, milk influences all aspects of neonatal development, especially immune function. All kinds of milks so far studied have contained a milk microbiome. In this review, we focus on what is known about the collection of bacterial members found in milk microbiomes. Milk microbiomes include members sourced from maternal and infant microbiomes and they appear to be influenced by maternal evolutionary history, diet, milk nutrients, and environment, as well as by random chance. Once a neonate begins nursing, microbes from milk colonize their gut and produce byproducts that influence their physiology, metabolism, and immune development. Empirical data on milk microbiomes outside of humans and model systems are sparse. Greater study of milk microbiomes across mammals will expand our understanding of mammalian evolution and improve the health of animals under human care.

Gestational and Developmental Contributors of Pediatric MASLD

Pediatric metabolic dysfunction-associated steatotic liver disease (MASLD) is common and can be seen as early as in utero. A growing body of literature suggests that gestational and early life exposures modify the risk of MASLD development in children. These include maternal risk factors, such as poor cardiometabolic health (e.g., obesity, gestational diabetes, rapid weight gain during pregnancy, and MASLD), as well as periconceptional dietary exposures, degree of physical activity, intestinal microbiome, and smoking. Paternal factors, such as diet and obesity, also appear to play a role. Beyond gestation, early life dietary exposures, as well as the rate of infant weight gain, may further modify the risk of future MASLD development. The mechanisms linking parental health and environmental exposures to pediatric MASLD are complex and not entirely understood. In conclusion, investigating gestational and developmental contributors to MASLD is critical and may identify future interventional targets for disease prevention.

Topics on maternal, fetal and neonatal immunology of dogs and cats

Birth and the first few weeks of age are critical periods of developing the immune system of puppies and kittens and adapting to an environment containing a variety of infectious agents. The survival rate during these periods depends mainly on the newborn's immune capacity to prevent and combat infections. Although most components of innate and adaptive immunity are present at birth, responses are slow and immature compared to adults. Due to immunological immaturity and the endotheliochorial placental structure, circulating concentrations of immunoglobulins in dogs and cats at birth are quite low. Thus, newborns need a prompt and immediate immune response, which is essentially provided by defense cells and maternal antibodies via colostrum. Failure to ingest colostrum is correlated with high mortality rates in the neonatal period. Concurrently, factors related to pregnant, such as pregnancy physiological immunosuppression and nutritional and health states, can directly influence newborn immunity and health. Therefore, understanding the maternal and neonatal immunological aspects, importance of colostrum, risk factors for failure to transfer passive immunity and colostrum substitute strategies are essential to ensure the survival of the litter.

Comparative Growth Outcomes in Preterm Infants Fed Either Mother's Own Milk or Donor Human Milk

Objective: To compare growth velocity (GV) in preterm infants fed mother's own milk (MOM) fortified with human milk-based fortifier (HMBF) to those who received donor human milk (DHM) fortified with HMBF. Study Design: A retrospective study of preterm infants with birth weight <1,250 g receiving an exclusive human milk diet. Maternal and infant charts were reviewed for feeding, growth, and short-term neonatal morbidities. Results: On regression analysis, after adjusting (gestational age, multiple births, antenatal steroids, and small for gestational age), no significant difference was observed between the two groups in GV from birth to 32 weeks postmenstrual age (β-coefficient 0.83, 95% confidence interval [CI]: -0.47 to 2.14, p = 0.21), GV from the day of regaining of birth weight to discharge (β-coefficient -0.015, 95% CI: -1.08 to 1.05, p = 0.98). The rate of Grade 3 and 4 intraventricular hemorrhage was significantly higher in the DHM group (19.6% compared to 5.5% in MOM, p = 0.03). Conclusion: At our institution, there was no difference in GV of preterm infants fed HMBF-fortified MOM versus HMBF-fortified DBM.

Effect of an exclusive human milk diet on feeding tolerance in preterm infants

OBJECTIVE

To compare the time to full enteral feeds in preterm infants fed exclusive human milk (EHM) - mother's own milk (MOM) fortified with human milk-based fortifier (HMBF), to those who received partial human milk (PHM) - MOM fortified with bovine milk-based fortifier (BMBF), and exclusive formula.

STUDY DESIGN

A single-center retrospective study of infants with birth weight <1250 g from 2013 to 2018. Data on feeding, growth and other short-term neonatal morbidities were collected.

RESULTS

On regression analysis, time to full enteral feeds was significantly higher in PHM compared to EHM group (β-coefficient 4.14, 95% CI 0.00-8.29) and formula-fed group compared to EHM (β-coefficient 4.3, 95% CI 0.32-8.20). No significant differences in growth velocity, length of stay and other morbidities were found between the groups.

CONCLUSION

Infants in EHM had better feeding tolerance and reached their enteral feed goals sooner compared to PHM and formula-fed groups.

Persistence of Anti SARS-CoV-2 Antibodies in Breast Milk from Infected and Vaccinated Women after In Vitro-Simulated Gastrointestinal Digestion

Breastfeeding is key for infant development and growth. Breast milk contains different bioactive compounds including antibodies. Recent studies have demonstrated the presence of breast milk SARS-CoV-2 antibodies after maternal infection and vaccination. However, the potential impact on the infant has not been explored yet. As a first step, we aimed at assessing the potential persistence of SARS-CoV-2 IgA and IgG antibodies from infected and vaccinated women in the gastrointestinal tract of the infants by means of an in vitro-simulated gastrointestinal digestion approach. Breast milk samples from 10 lactating women receiving mRNA vaccination against SARS-CoV-2 (n = 5 with BNT162b2 mRNA and n = 5 with mRNA-1273) and also, COVID-19 infected (n = 5) were included. A control group with women with no exposure to the virus (n = 10 pre-pandemic) were also studied. The presence of IgA and IgG SARS-CoV-2 antibody levels was determined by ELISA after the gastric and intestinal stages. The impact of digested antibodies on infant gut microbiota was tested by simulating colonic fermentation with two different fecal inoculums: infants from vaccinated and non-vaccinated mothers. Specific gut microbial groups were tested by targeted qPCR. In vitro infant gastrointestinal digestion significantly decreased the levels of both anti-SARS-CoV-2 IgA and IgG. However, both remained resistant in all the study groups except in that evaluating breast milk samples from infected women, in which IgG was degraded below the cut-off values in the intestinal phase. No effect of the antibodies on microbiota were identified after digestion. In conclusion, antibody levels against SARS-CoV-2 are reduced after in vitro-simulated gastrointestinal tract but remain present, so a positive biological effect could be expected from this infant immunization pathway.

Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior

Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.

Exclusive Maternal Milk Compared With Exclusive Formula on Growth and Health Outcomes in Very-Low-Birthweight Preterm Infants: Phase II of the Pre-B Project and an Evidence Analysis Center Systematic Review

As part of the Pre-B Project, a systematic review was conducted to evaluate associations between exclusive maternal milk (≥75%) intake and exclusive formula intake and growth and health outcomes in very-low-birthweight (VLBW) preterm infants. The protocols from the Academy of Nutrition and Dietetics' Evidence Analysis Center and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist were followed. Thirteen observational studies were included; 11 studies reported data that could be synthesized in a pooled analysis. The evidence is very uncertain (very low quality) about the effect of exclusive maternal milk on all outcomes due to observational study designs and risk of selection, performance, detection, and reporting bias in most of the included studies. Very-low-quality evidence suggested that providing VLBW preterm infants with exclusive maternal milk was not associated with mortality, risk of necrotizing enterocolitis, sepsis, or developing bronchopulmonary dysplasia, as compared with exclusive preterm formula, but exclusive maternal milk was associated with a lower risk of retinopathy of prematurity (very low certainty). Results may change when additional studies are conducted. There was no difference in weight, length, and head circumference gain between infants fed fortified exclusive maternal milk and infants receiving exclusive preterm formula; however, weight and length gain were lower in infants fed non-fortified exclusive maternal milk. Given the observational nature of human milk research, cause-and-effect evidence was lacking for VLBW preterm infants.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=86829, PROSPERO ID: CRD42018086829.

The establishment of the gut microbiota in 1-year-aged infants: from birth to family food

Purpose

With the aim of characterizing the gastrointestinal (GI) microbiota and contextually determine how different prenatal, perinatal, and postnatal factors affected its composition in early childhood, infants were enrolled in a longitudinal-prospective study named “A.MA.MI.” (Alimentazione MAmma e bambino nei primi MIlle giorni; NCT04122612, October 2019).

Methods

Forty-five fecal samples were collected at 12 months of infants’ age, identified as the 3rd follow-up (T3). The evaluated variables were pre-gestational weight and weight gain during pregnancy, delivery mode, feeding, timing of weaning, and presence/absence of older siblings. Fecal alpha and beta-diversities were analyzed. Noteworthy, to determine the impact of the influencing factors, multivariate analyses were conducted.

Results

At T3, all prenatal and perinatal variables did not result to be significant whereas, among the postnatal variables, type of milk-feeding and weaning showed the greatest contribution in shaping the microbiota. Although aged 1 year, infants exclusively breastfed until 6 months were mainly colonized by Lactobacillaceae and Enterobacteriaceae. Differently, Bacteroidaceae characterized the microbiota of infants that were never breastfed in an exclusive way. Moreover, although an early introduction of solid foods determined higher values of Faith’s PD, high abundances of Ruminococcaceae and Faecalibacterium mainly associated with infants weaned after the 4th month of age.

Conclusion

The microbial colonization during the first year of life is likely affected by a simultaneous effect of multiple variables playing a significant role at different times. Therefore, these data contribute to add evidence concerning the complex multifactorial interaction between GI microbiota and various stimuli affecting infants during the early stages of life.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-022-02822-1.

Peptides Derived from In Vitro and In Vivo Digestion of Human Milk Are Immunomodulatory in THP-1 Human Macrophages

BACKGROUND

Milk proteins contain many encrypted bioactive peptides. Whether these bioactive peptides are released in the infant intestine and exert immunomodulatory activity remains unknown.

OBJECTIVE

This study examined in vitro immunomodulatory activities of peptides from in vitro- and in vivo-digested human milk.

METHODS

Peptides were extracted from in vitro-digested human milk and pooled intestinal samples from 8 infants fed human milk. Peptides extracted from in vitro-digested samples were fractionated. The in vitro effects of these peptides and fractions on the secretion of TNF-α and IL-8 in LPS-treated human immune THP-1 macrophages were evaluated. The significance of differences between in vitro peptide fraction treatment and control on cytokine production was analyzed by t test. LC-MS/MS-based peptidomics was conducted to identify the peptides. The peptides were screened for potential bioactivity using a sequence homology search using the Milk Bioactive Peptide Database (MBPDB).

RESULTS

Six fractions of the peptide mixture extracted from the in vitro-digested human milk significantly inhibited TNF-α production by LPS-challenged THP-1 macrophages. Fractions F4, F8, F11, F14, and F17 attenuated IL-8 secretion, and F6/7 and F18 increased IL-8 secretion. Peptides extracted from the pooled in vivo intestinal samples attenuated both TNF-α and IL-8 secretion. There were 266 and 418 peptides identified in the in vitro and in vivo samples, respectively. Among the peptides, 34 and 50 in the in vitro and in vivo samples, respectively, had >80% sequence similarity to bioactive peptides in the MBPDB.

CONCLUSIONS

Peptides released by in vitro and in vivo infant digestion of human milk were immunomodulatory in human immune cells; fractions F4, F8, and F11 were anti-inflammatory; and F6/7 and F18 were proinflammatory. Thirteen peptides were present in all fractions with anti-inflammatory activity, and 38 peptides were present in all fractions with proinflammatory activity. These peptides potentially contributed to the observed immunomodulatory activity of the peptide mixtures.

The impact of the gut microbiome on toxigenic bacteria

Millions of symbiotic and pathogenic microorganisms known as microbiota colonize the host body. The microbiome plays an important role in human health and colonizes hundreds of different species of multicellular organisms so that they are introduced as the metaorganisms. Changes in the microbial population of the gut microbiome may cause resistance to pathogenic bacteria-induced infection. Understanding the principles of Host-Microbiota Interactions (HMIs) is important because it clarifies our insight towards the mechanisms of infections established in the host. Interactions between the host and the microbiota help answer the question of how a microorganism can contribute to the health or disease of the host. Microbiota can increase host resistance to colonization of pathogenic species. Studying the HMIs network can in several ways delineate the pathogenic mechanisms of pathogens and thereby help to increase useful and novel therapeutic pathways. For example, the potentially unique microbial effects that target the distinct host or interfere with the endogenous host interactions can be identified. In addition, the way mutations in essential proteins in the host and/or in the microbes can influence the interactions between them may be determined. Furthermore, HMIs help in identifying host cell regulatory modules.

Impact of early life nutrition on gut health in children: a prospective clinical study

INTRODUCTION

The first 1000 days of life could contribute to individual susceptibility to the later development of chronic non-communicable diseases. Nutrition in early life appears to be an important determinant factor for a sustainable child's health. In this study, we propose to investigate the impact of exclusive breast feeding on gut health in children.

METHODS AND ANALYSIS

A prospective cohort of newborns (n=350) will be recruited at birth and followed up to 4 years of age. The main objective is to evaluate the link between exclusive breast feeding for at least 3 months and the gut health of the child at 4 years. The primary endpoint of assessment of gut health will be based on the non-invasive measurement of faecal secretory IgA (sIgA) as a sensitive biomarker of the intestinal ecosystem. The presence of gastrointestinal disorders will be defined according to the clinical criteria of Rome IV. Information on parent's nutritional habits and life style, breastfeeding duration and child's complementary feeding will be collected along the follow-up. Cord blood cells and plasma at birth will be purified for further analysis. The meconium and stools collected at birth, 6 months, 2 years and 4 years of age will allow sIgA analysis.

ETHICS AND DISSEMINATION

This clinical study has obtained the approval from the national ethical committee. We plan to publish the results of the study in peer-review journals and by means of national and international conference.

TRIAL REGISTRATION NUMBER

NCT04195425.

Dysregulated metabolism and behaviors by disrupting gut microbiota in prenatal and neonatal mice

The live microbiota ecosystem in the intestine plays a critical role in maintaining the normal physiological and psychological functions in both animals and human beings. However, the chronic effect of microbiota disturbances during prenatal and neonatal developing periods on animal's health remains less studied. In the current study, pregnant ICR mice were fed with an antibiotic diet (7-g nebacitin [bacitracin-neomycin sulphate 2:1]/kg standard diet) from day 14 of conception, and their offspring were provided with the same diet till the termination of the experiments. Dams treated with antibiotics showed increased body weight along with enlarged gut. Antibiotic-treated offspring revealed decreased bodyweight, increased food, water, and sucrose intake. Administration of antibiotics affected corticosterone responsivity to acute 20 min restraint challenge in male pups. In behavior tests, female pups showed decreased movement in open field while male pups revealed decreased latency to open arms in elevated plus maze test and immobility time in tail suspension test. Together, these results suggested that early antibiotic exposure may impact on the food intake, body weight gain, and emotional behavior regulation in mice.

Intestinal Microbiota in Common Chronic Inflammatory Disorders Affecting Children

The incidence and prevalence rate of chronic inflammatory disorders is on the rise in the pediatric population. Recent research indicates the crucial role of interactions between the altered intestinal microbiome and the immune system in the pathogenesis of several chronic inflammatory disorders in children, such as inflammatory bowel disease (IBD) and autoimmune diseases, such as type 1 diabetes mellitus (T1DM) and celiac disease (CeD). Here, we review recent knowledge concerning the pathogenic mechanisms underlying these disorders, and summarize the facts suggesting that the initiation and progression of IBD, T1DM, and CeD can be partially attributed to disturbances in the patterns of composition and abundance of the gut microbiota. The standard available therapies for chronic inflammatory disorders in children largely aim to treat symptoms. Although constant efforts are being made to maximize the quality of life for children in the long-term, sustained improvements are still difficult to achieve. Additional challenges are the changing physiology associated with growth and development of children, a population that is particularly susceptible to medication-related adverse effects. In this review, we explore new promising therapeutic approaches aimed at modulation of either gut microbiota or the activity of the immune system to induce a long-lasting remission of chronic inflammatory disorders. Recent preclinical studies and clinical trials have evaluated new approaches, for instance the adoptive transfer of immune cells, with genetically engineered regulatory T cells expressing antigen-specific chimeric antigen receptors. These approaches have revolutionized cancer treatments and have the potential for the protection of high-risk children from developing autoimmune diseases and effective management of inflammatory disorders. The review also focuses on the findings of studies that indicate that the responses to a variety of immunotherapies can be enhanced by strategic manipulation of gut microbiota, thus emphasizing on the importance of proper interaction between the gut microbiota and immune system for sustained health benefits and improvement of the quality of life of pediatric patients.

Maternal Distress and Social Support Are Linked to Human Milk Immune Properties

Possible alterations of maternal immune function due to psychological stress may reflect immunoactive factor levels in breast milk. This study aimed to assess the association between maternal distress and breast milk levels of secretory IgA (SIgA), IgM, IgG, and lactoferrin (LF). We hypothesized that this association is moderated by maternal social support achieved from others during lactation. The study group included 103 lactating mothers and their healthy five-month-old infants. Maternal distress was determined based on the State Anxiety Inventory and the level of salivary cortisol. Social support was assessed using the Berlin Social Support Scales. Breast milk samples were collected to test for SIgA, IgM, IgG, and LF using the ELISA method. Milk immunoactive factors were regressed against maternal anxiety, social support, salivary cortisol, and infant gestational age using the general regression model. Maternal anxiety was negatively associated with milk levels of LF (β = -0.23, p = 0.028) and SIgA (β = -0.30, p = 0.004), while social support was positively associated with milk IgG (β = 0.25, p = 0.017). Neither anxiety nor social support were related to milk IgM. No association was found between the level of maternal salivary cortisol and immunoactive factors in milk. Our results suggest that maternal psychological wellbeing and social support may affect milk immune properties.

Lactoferrin and Immunoglobulin Concentrations in Milk of Gestational Diabetic Mothers

Gestational diabetes mellitus (GDM) is associated with an increased risk of having a high-care newborn and has an impact on maternal wellbeing. This study aimed to assess the effect of GDM on the lactoferrin (LF), secretory immunoglobulin A (SIgA), immunoglobulin G (IgG), and immunoglobulin M (IgM) concentrations in early colostrum, colostrum, and transitional milk samples of hyperglycemic (n = 53) and normoglycemic (n = 49) mothers using enzyme-linked immunosorbent assay (ELISA). The concentrations of milk lactoferrin and SIgA, but not IgG and IgM, from hyperglycemic and normoglycemic mothers, showed a similar negative correlation with lactation from the first to the fifteenth day. Apart from early colostral IgG, there were no differences in concentrations of LF and immunoglobulins in milk from hyperglycemic and normoglycemic mothers. For hyperglycemia compensated by diet (GDM G1) or insulin treatment (GDM G2), slight differences were seen for LF and IgG, but not for SIgA and IgM, during an early stage of lactation only. Early colostral IgG and colostral LF of insulin-treated mothers were higher (10.01 ± 4.48 mg/L and 11.50 ± 0.58 g/L, respectively) than for diet-control diabetic mothers (7.65 ± 5.67 mg/L and 8.05 ± 1.38 g/L, respectively). GDM of mothers does not have a significant impact on immunological quality of early milk.

Role of Polymeric Immunoglobulin Receptor in IgA and IgM Transcytosis

Transcytosis of polymeric IgA and IgM from the basolateral surface to the apical side of the epithelium and subsequent secretion into mucosal fluids are mediated by the polymeric immunoglobulin receptor (pIgR). Secreted IgA and IgM have vital roles in mucosal immunity in response to pathogenic infections. Binding and recognition of polymeric IgA and IgM by pIgR require the joining chain (J chain), a small protein essential in the formation and stabilization of polymeric Ig structures. Recent studies have identified marginal zone B and B1 cell-specific protein (MZB1) as a novel regulator of polymeric IgA and IgM formation. MZB1 might facilitate IgA and IgM transcytosis by promoting the binding of J chain to Ig. In this review, we discuss the roles of pIgR in transcytosis of IgA and IgM, the roles of J chain in the formation of polymeric IgA and IgM and recognition by pIgR, and focus particularly on recent progress in understanding the roles of MZB1, a molecular chaperone protein.

Sex-dependent modulation of immune development in mice by secretory IgA-coated Lactobacillus reuteri isolated from breast milk

Lactobacilli, commonly present in human breast milk, appear to colonize the neonatal gut and provide protection to infants against various infections, thereby promoting immune development. This study examined the potential probiotic role of breast milk-derived Lactobacillus reuteri FN041 in immune development in mice. The FN041 were gavaged either to BALB/c dams (n = 6/group) during the lactation period or to their offspring (n = 6/sex per intervention) after weaning separately (cointervention). All interventions induced increased intestinal barriers in 5-wk-old offspring, especially in the females. Immunoglobulin A plasmocytes in ileal tissue and secretory IgA (sIgA) in ileal contents increased in all 5-wk-old offspring of cointervention. The activation of mRNA expression of 17 genes was sex-dependent, especially in 5-wk-old offspring. Broader genes were regulated in female mice. The effect of cointervention on the Shannon index of total microbiota is sex-related. The Shannon index of sIgA-coated microbiota increased in both sexes. The sIgA-coated microbiota showed intergroup differences according to β diversity, especially in female mice that showed an increase in Bifidobacterium of Actinobacteria. The sIgA-coated Bifidobacterium was positively correlated with mRNA expression of Tlr9. The sIgA-coated Lactobacillus in male offspring was negatively correlated with mRNA expression of Cldn2. In conclusion, L. reuteri FN041 promoted the production of intestinal sIgA and the expression of genes related to antimicrobial peptides in the offspring and enhanced the function of the mucosal barrier, depending on sex and treatment manner.

Diet and Nutrition in Pediatric Inflammatory Bowel Diseases

Both genetic and environmental factors are involved in the onset of inflammatory bowel disease (IBD). In particular, diet composition is suspected to significantly contribute to IBD risk. In recent years, major interest has raised about the role of nutrition in disease pathogenesis and course, and many studies have shown a clear link between diet composition and intestinal permeability impairment. Moreover, many IBD-related factors, such as poor dietary intake, nutrients loss and drugs interact with nutritional status, thus paving the way for the development of many therapeutic strategies in which nutrition represents the cornerstone, either as first-line therapy or as reversing nutritional deficiencies and malnutrition in IBD patients. Exclusive enteral nutrition (EEN) is the most rigorously supported dietary intervention for the treatment of Crohn's Disease (CD), but is burdened by a low tolerability, especially in pediatric patients. Promising alternative regimens are represented by Crohn's Disease Exclusion Diet (CDED), and other elimination diets, whose use is gradually spreading. The aim of the current paper is to provide a comprehensive and updated overview on the latest evidence about the role of nutrition and diet in pediatric IBD, focusing on the different nutritional interventions available for the management of the disease.

The Gut‒Breast Axis: Programming Health for Life

The gut is a pivotal organ in health and disease. The events that take place in the gut during early life contribute to the programming, shaping and tuning of distant organs, having lifelong consequences. In this context, the maternal gut plays a quintessence in programming the mammary gland to face the nutritional, microbiological, immunological, and neuroendocrine requirements of the growing infant. Subsequently, human colostrum and milk provides the infant with an impressive array of nutrients and bioactive components, including microbes, immune cells, and stem cells. Therefore, the axis linking the maternal gut, the breast, and the infant gut seems crucial for a correct infant growth and development. The aim of this article is not to perform a systematic review of the human milk components but to provide an insight of their extremely complex interactions, which render human milk a unique functional food and explain why this biological fluid still truly remains as a scientific enigma.

Role of diet and nutrition in inflammatory bowel disease

Inflammatory bowel diseases (IBDs) are closely linked to nutrition. The latest research indicates that diet and nutrition are significantly involved in the etiopathogenesis of the disease, although their specific role throughout its clinical course still remains unclear. This study reviewed how diet and nutrition are associated with IBD development and management. Even though specific diets have been shown to bring about positive outcomes, there is currently no scientific consensus regarding an appropriate diet that would benefit all IBD patients. We suggest that individualized dietary recommendations are of the greatest importance and that diets should be planned to provide individual IBD patients with specific nutrient requirements while keeping all the clinical aspects of the patients in mind. Further research is clearly necessary to investigate nutritional factors involved in IBD development and, especially, to evaluate the applications of the diets during the course of the disease.

Long-Chain Polyunsaturated Fatty Acids (LCPUFAs) and the Developing Immune System: A Narrative Review

The immune system is complex: it involves many cell types and numerous chemical mediators. An immature immune response increases susceptibility to infection, whilst imbalances amongst immune components leading to loss of tolerance can result in immune-mediated diseases including food allergies. Babies are born with an immature immune response. The immune system develops in early life and breast feeding promotes immune maturation and protects against infections and may protect against allergies. The long-chain polyunsaturated fatty acids (LCPUFAs) arachidonic acid (AA) and docosahexaenoic acid (DHA) are considered to be important components of breast milk. AA, eicosapentaenoic acid (EPA) and DHA are also present in the membranes of cells of the immune system and act through multiple interacting mechanisms to influence immune function. The effects of AA and of mediators derived from AA are often different from the effects of the n-3 LCPUFAs (i.e., EPA and DHA) and of mediators derived from them. Studies of supplemental n-3 LCPUFAs in pregnant women show some effects on cord blood immune cells and their responses. These studies also demonstrate reduced sensitisation of infants to egg, reduced risk and severity of atopic dermatitis in the first year of life, and reduced persistent wheeze and asthma at ages 3 to 5 years, especially in children of mothers with low habitual intake of n-3 LCPUFAs. Immune markers in preterm and term infants fed formula with AA and DHA were similar to those in infants fed human milk, whereas those in infants fed formula without LCPUFAs were not. Infants who received formula plus LCPUFAs (both AA and DHA) showed a reduced risk of allergic disease and respiratory illness than infants who received standard formula. Studies in which infants received n-3 LCPUFAs report immune differences from controls that suggest better immune maturation and they show lower risk of allergic disease and respiratory illness over the first years of life. Taken together, these findings suggest that LCPUFAs play a role in immune development that is of clinical significance, particularly with regard to allergic sensitisation and allergic manifestations including wheeze and asthma.

Gut microbiota and inflammatory bowel disease: The current status and perspectives

Inflammatory bowel disease (IBD) is a chronic immune-mediated disease that affects the gastrointestinal tract. It is argued that environment, microbiome, and immune-mediated factors interact in a genetically susceptible host to trigger IBD. Recently, there has been increased interest in the development, progression, and treatment of IBD because of our understanding of the microbiome. Researchers have proved that some factors can alter the microbiome and the pathogenesis of IBD. As a result, there has been increasing interest in the application of probiotics, prebiotics, antibiotics, fecal microbiota transplantation, and gene manipulation in treating IBD because of the possible curative effect of microbiome-modulating interventions. In this review, we summarize the findings from human and animal studies and discuss the effect of the gut microbiome in treating patients with IBD.

Faecal transplantation and Clostridioides difficile infection

Faecal microbiota transplantation (FMT), known equally well as faecal transplantation or faecal bacteriotherapy, is the process of implanting the faecal suspension containing balanced microbiota from a healthy donor to the colon of a recipient patient. Excessive growth of Clostridioides difficile (C difficile) in the intestinal microbiota resulting from antibiotic consumption is currently a rising threat to public health. FMT is one of the most important, newer approaches to treating C difficile infections. Since C difficile is regarded as an opportunistic bacterium triggering disease in conditions of disturbed homeostasis of the intestinal microbiota, restoration of healthy intestinal microflora facilitates suppression of toxic strain of C difficile by anaerobic bacteria of normal intestinal microflora with concomitant cure. Nurses have important role in caring for patients after faecal transplantation.

Epidemiology and Pathogenesis of Ulcerative Colitis

Ulcerative colitis (UC) is a complex chronic, immune-mediated inflammatory disorder of the colon. Factors associated with increased risk of UC include diet, particularly Western diet influences in newly industrialized nations, medications, and lifestyle factors that may influence the host's microbiome or immune response to antigens. Although much evidence identifying potential genetic and host-related factors is currently available, there are still many unanswered questions. As the global UC incidence and prevalence continues to increase, there are multiple opportunities for continued investigation to clarify our understanding of UC, identify potential predictors of disease severity, response to therapy, and novel therapeutic targets.

Changes in Human Milk Immunoglobulin Profile During Prolonged Lactation

Mother's milk immunoglobulins (Igs) delivered to infants during breastfeeding are crucial in shaping and modulating immature infants' immune system and provide efficient protection against pathogens. The aim of the study was to evaluate the immunoglobulin concentrations in milk of 116 lactating mothers over prolonged lactation from the 1st to the 48th month using the ELISA method. The concentration of proteins, SIgA and IgG, but not IgM, showed a positive correlation (r = 0.69, p < 0.005; r = 0.54, p < 0.05; and r = 0.27, p < 0.05, respectively) with lactation from the 1st to the 48th month. The lowest concentrations of SIgA and IgG were observed for the first year (2.12 ± 0.62 g/L and 14.71 ± 6.18 mg/L, respectively) and the highest after the 2nd year of lactation (7.55 ± 7.16 g/L and 18.95 ± 6.76 mg/L, respectively). The IgM concentration remained stable during 2 years (2.81 ± 2.74 mg/L), but after 24 months it was higher (3.82 ± 3.05 mg/L), although not significantly. Moreover, negative correlations of protein (r = -0.24, p < 0.05) and SIgA (r = -0.47, p < 0.05) concentrations with the number of feedings were found. Human milk after the 2nd year of lactation contains significantly higher concentrations of protein, SIgA, and IgG. High concentration of immunoglobulins and protein during prolonged lactation is an additional argument to support breastfeeding even after introducing solid foods and should be one of the overarching goals in the protection of children's health.

A Biotic Support During Pregnancy to Strengthen the Gastrointestinal Performance in Puppies

Up to 60% of neonates can be affected by gastroenteritis due to specific pathogens or aspecific polymicrobial interactions. The present study evaluated if a dietary supplementation with MOS, FOS, E. faecium and L. acidophilus in pregnancy may reduce gastroenteritis in puppies. Fifteen Great Danes were divided in 3 groups. The control group (CG) ate a standard diet. In 2 study groups, the diet was supplemented with pre- and probiotics during the last (1WG) and the last 4 pregnancy weeks (4WG). Up to 9 weeks, puppies were checked daily to identify first- or second- presentation gastroenteritis. Data were processed by χ² (P < 0.05). First-presentation gastroenteritis was more frequent in CG than in 1WG than in 4WG. Second-presentation gastroenteritis was more frequent in CG than in 1 and 4WG. Puppies from pre- and probiotics supplemented bitches were less prone to gastroenteritis. 1 or 4WG equally reduced second-presentation gastroenteritis in puppies, but 4WG was better than 1WG on first-presentation gastroenteritis. By entero-mammary link, supplemented bitches produced higher immune quality colostrum, thus puppies faced immunitary challenges better; moreover, maternal microbiota, positively altered by supplementation, was transferred to newborns, becoming more resistant to gastroenteritis. This information can be useful in clinical practice with the goal of preventing gastroenteritis in puppies and reducing its prevalence and severity.

The microbiome and inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic immune-mediated disease affecting the gastrointestinal tract. IBD consists of 2 subtypes: ulcerative colitis and Crohn disease. IBD is thought to develop as a result of interactions between environmental, microbial, and immune-mediated factors in a genetically susceptible host. Of late, the potential role of the microbiome in the development, progression, and treatment of IBD has been a subject of considerable interest and enquiry. Indeed, studies in human subjects have shown that the gut microbiome is different in patients with IBD compared with that in healthy control subjects. Other evidence in support of a fundamental role for the microbiome in patients with IBD includes identification of mutations in genes involved in microbiome-immune interactions among patients with IBD and epidemiologic observations implicating such microbiota-modulating risk factors as antibiotic use, cigarette smoking, levels of sanitation, and diet in the pathogenesis of IBD. Consequently, there has been much interest in the possible benefits of microbiome-modulating interventions, such as probiotics, prebiotics, antibiotics, fecal microbiota transplantation, and gene manipulation in the treatment of IBD. In this review we will discuss the role of the gut microbiome in patients with IBD; our focus will be on human studies.

Maternal Immunization: Nature Meets Nurture

Vaccinating women in pregnancy (i.e., maternal immunization) has emerged as a promising tool to tackle infant morbidity and mortality worldwide. This approach nurtures a 'gift of nature,' whereby antibody is transferred from mother to fetus transplacentally during pregnancy, or postnatally in breast milk, thereby providing passive, antigen-specific protection against infections in the first few months of life, a period of increased immune vulnerability for the infant. In this review, we briefly summarize the rationale for maternal immunization programs and the landscape of vaccines currently in use or in the pipeline. We then direct the focus to the underlying biological phenomena, including the main mechanisms by which maternally derived antibody is transferred efficiently to the infant, at the placental interface or in breast milk; important research models and methodological approaches to interrogate these processes, particularly in the context of recent advances in systems vaccinology; the potential biological and clinical impact of high maternal antibody titres on neonatal ontogeny and subsequent infant vaccine responses; and key vaccine- and host-related factors influencing the maternal-infant dyad across different environments. Finally, we outline important gaps in knowledge and suggest future avenues of research on this topic, proposing potential strategies to ensure optimal testing, delivery and implementation of maternal vaccination programs worldwide.

Microbial biodiversity in the throats of pulmonary tuberculosis patients and tuberculin skin test (TST) positive and negative healthy individuals in Malaysia

The purpose of this study was to investigate the composition of throat microbiota in pulmonary tuberculosis patients (PTB) in comparison to healthy tuberculin skin test positive (TSTp) and negative (TSTn) individuals. Throat swabs samples were collected, and the microbiota was characterized. Richer operational taxonomic units (OTUs) were present in PTB group, compared to TSTp and TSTn. Regarding alpha diversity analysis there was a higher community diversity in TSTn compared to TSTp. Beta diversity analysis showed different species composition in TSTp compared to TSTn and PTB. There was higher presence of Firmicutes in PTB and TSTn compared to TSTp group at phylum level. At the genus level, Leuconostoc and Enterococcus were higher in TSTn compared to TSTp and Pediococcus, Chryseobacterium, Bifidobacterium, Butyrivibrio, and Bulleidia were higher in PTB compared to TSTn. Streptococcus was higher in TSTn compared to PTB and Lactobacillus in PTB compared to TSTp. At species level, Streptococcus sobrinus and Bulleidia moorei were higher in PTB compared to TSTn individuals, while Lactobacillus salivarius was higher in PTB compared to TSTp. The differences in the microbiome composition could influence the resistance/susceptibility to Mtb infection.

Hypoxia Inducible Factor-1α: The Curator of Gut Homeostasis

The human gut microbiome is a stratified and resilient ecosystem co-inhabited by a diverse and dynamic pool of microorganisms. Microbial selection, establishment, and colonization are modulated through a complex molecular network of host-microbial interactions. These molecular bioprocesses ensure the taxonomic composition of the mature human gut microbiome. The human gut microbiome plays a vital role in host health; otherwise, any microbial dysbiosis could predispose to the onset of physiological and metabolic disorder/s. Focussed research are being carried out to identify key molecular agents defining gut homeostasis. These molecules hold the potential to develop effective therapeutic solutions for microbial dysbiosis-associated human disorders. Of these, Hypoxia-inducible factor-1α (HIF-1α) is a central player in host-microbial crosstalk to maintain gut homeostasis. Human gut microbial metabolites regulate its cellular stability, which in turn regulates various cellular processes required for the stable gut microbiome. In the present review, an effort has been made to summarize the key role of HIF-1α to maintain gut homeostasis.

Human microbiome and homeostasis: insights into the key role of prebiotics, probiotics, and symbiotics

The interest in the study of the gut microbiome has grown exponentially. Indeed, its impact on health and disease has been increasingly reported, and the importance of keeping gut microbiome homeostasis clearly highlighted. However, and despite many advances, there are still some gaps, as well as the real discernment on the contribution of some species falls far short of what is needed. Anyway, it is already more than a solid fact of its importance in maintaining health and preventing disease, as well as in the treatment of some pathologies. In this sense, and given the existence of some ambiguous opinions, the present review aims to discuss the importance of gut microbiome in homeostasis maintenance, and even the role of probiotics, prebiotics, and symbiotics in both health promotion and disease prevention.

Solely human milk diets for preterm infants

Human milk provides not only ideal nutrition for infant development but also immunologic factors to protect from infection and inflammation. For the newborn preterm infant, the natural delivery of milk is not attainable, and instead pumped maternal milk, donor human milk, and human milk fortification are mainstays of clinical care. Current research demonstrates a decreased risk of necrotizing enterocolitis with maternal milk and donor human milk when individually compared to formula and with a complete human milk diet of maternal milk supplemented with donor human milk. The incidence of severe retinopathy of prematurity is decreased with an exclusive human milk diet, and this decrease is more pronounced with human milk-based compared to bovine milk-based human milk fortifier. The incidence of other morbidities such as late-onset sepsis and bronchopulmonary dysplasia is decreased with higher dose of human milk though significant differences are not apparent in exclusive human milk diet studies.

Passive immune transfer in puppies

The puppy, born without immunoglobulins G (IgG), acquires a passive systemic immunity thanks to colostrum intake during the two first days of life. The quality of passive immune transfer (i.e. blood IgG concentration at two days of age), highly variable between litters and between puppies within litters, depends mainly on the time elapsed between birth and ingestion of colostrum, with limited influence of colostrum IgG concentration. Deficit in passive immune transfer, impacting puppy's health and neonatal mortality rate, can be indirectly diagnosed through blood gammaglutamyltransferases assay and evaluation of growth rate over the two first days of life. In the absence of maternal colostrum, few homo- and heterospecific immune sources are available and canine colostrum banking remains the optimal solution. Whereas passive immune transfer is crucial for survival during the neonatal period, it later interferes with response to vaccination. In addition to systemic passive immune transfer, maternal antibodies (mainly IgA) would provide local (digestive) immunity, ensuring mid-term protection of the puppies' gut together with probably long term training of the digestive immune system.

Drinking Warm Water Improves Growth Performance and Optimizes the Gut Microbiota in Early Postweaning Rabbits during Winter

Accumulating evidence indicates that cold exposure changes the composition of the gut microbiota and reduces intestinal immunity in early postweaning livestock. However, little is known about the effects of drinking warm water (WW) on gut microbiota during winter. In this study, we investigated the effects of drinking WW in winter on the growth performance and gut microbiota structure of rabbits raised in poorly insulated housing from the early postweaning period (day 46) to the subadult period (day 82). The average daily gain and feed conversion ratio in rabbits drinking WW were significantly improved compared to those of the rabbits drinking cold water (CW) during 47-58 days. In addition, rabbits drinking WW had a significantly decreased the risk of diarrhea during 71-82 days. 16S rRNA sequence analysis revealed that the alpha diversity of the cecal microbiota was not significantly different between the WW and CW groups, but significantly increased with age. The relative abundance of cecal microorganisms, such as Coprococcus spp. was considerably increased at day 70 in the group drinking WW. Correlation analysis indicated that Coprococcus spp. was negatively associated with pro-inflammatory factors. In conclusion, our results suggest that drinking WW has a positive effect on growth performance and gut microbiota in rabbits during the early postweaning stage in winter.

Metaproteomic investigation to assess gut microbiota shaping in newborn mice: A combined taxonomic, functional and quantitative approach

Breastfeeding is nowadays known to be one of the most critical factors contributing to the development of an efficient immune system. In the last decade, a consistent number of pieces of evidence demonstrated the relationship between a healthy organism and its gut microbiota. However, this link is still not fully understood and requires further investigation. We recently adopted a murine model to describe the impact of either maternal milk or parental genetic background, on the composition of the gut microbial population in the first weeks of life. A metaproteomic approach to such complex environments is a big challenge that requires a strong effort in both data production and analysis, including the set-up of dedicated multitasking bioinformatics pipelines. Herein we present an LC-MS/MS based investigation to monitor mouse gut microbiota in the early life, aiming at characterizing its functions and metabolic activities together with a taxonomic description in terms of operational taxonomic units. We provided a quantitative evaluation of bacterial metaproteins, taking into account differential expression results in relation to the functional and taxonomic classification, particularly with proteins from orthologues groups. This allowed the reduction of the bias arising from the presence of a high number of shared peptides, and proteins, among different bacterial species. We also focused on host mucosal proteome and its modulation, according to different microbiota composition. SIGNIFICANCE: This paper would represent a reference work for investigations on gut microbiota in early life, from both a microbiological and a functional proteomic point of view. We focused on the shaping of the mouse gut microbiota in dependence on the feeding modality, defining a reliable taxonomic description, highlighting some functional characteristics of the microbial community, and performing a first quantitative evaluation by data independent analysis in metaproteomics.

Infant Complementary Feeding of Prebiotics for theMicrobiome and Immunity

Complementary feeding transitions infants from a milk-based diet to solid foods, providing essential nutrients to the infant and the developing gut microbiome while influencing immune development. Some of the earliest microbial colonisers readily ferment select oligosaccharides, influencing the ongoing establishment of the microbiome. Non-digestible oligosaccharides in prebiotic-supplemented formula and human milk oligosaccharides promote commensal immune-modulating bacteria such as Bifidobacterium, which decrease in abundance during weaning. Incorporating complex, bifidogenic, non-digestible carbohydrates during the transition to solid foods may present an opportunity to feed commensal bacteria and promote balanced concentrations of beneficial short chain fatty acid concentrations and vitamins that support gut barrier maturation and immunity throughout the complementary feeding window.

Variation among populations in the immune protein composition of mother's milk reflects subsistence pattern

LAY SUMMARY

Adaptive immune proteins in mothers' milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother's environment throughout her life.

BACKGROUND AND OBJECTIVES

Mother's milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant's developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother's immunological exposures throughout her life. In this study, we examine the composition of innate and acquired immune proteins in milk across seven populations with diverse disease and cultural ecologies.

METHODOLOGY

Milk samples (n = 164) were collected in Argentina, Bolivia, Nepal, Namibia, Philippines, Poland and the USA. Populations were classified as having one of four subsistence patterns: urban-industrialism, rural-shop, horticulturalist-forager or agro-pastoralism. Milk innate (lactalbumin, lactoferrin and lysozyme) and acquired (Secretory IgA, IgG and IgM) protein concentrations were determined using triple-quadrupole mass spectrometry.

RESULTS

Both innate and acquired immune protein composition in milk varied among populations, though the acquired immune protein composition of milk differed more among populations. Populations living in closer geographic proximity or having similar subsistence strategies (e.g. agro-pastoralists from Nepal and Namibia) had more similar milk immune protein compositions. Agro-pastoralists had different milk innate immune protein composition from horticulturalist-foragers and urban-industrialists. Acquired immune protein composition differed among all subsistence strategies except horticulturist-foragers and rural-shop.

CONCLUSIONS AND IMPLICATIONS

Our results reveal fundamental variation in milk composition that has not been previously explored in human milk research. Further study is needed to understand what specific aspects of the local environment influence milk composition and the effects this variation may have on infant health outcomes.

Origination, change, and modulation of geriatric disease-related gut microbiota during life

The age-related changes in the diversity and composition of the gut microbiota are well described in recent studies. These changes have been suggested to be influenced by age-associated weakening of the immune system and low-grade chronic inflammation, resulting in numerous age-associated pathological conditions. Gut microbiota homeostasis is important throughout the life of the host by providing vital functions to regulate various immunological functions and homeostasis. Based on published results, we summarize the relationship between the gut microbiota and aging-related diseases, especially Parkinson's disease, immunosenescence, rheumatoid arthritis, bone loss, and metabolic syndrome. The change in composition of the gut microbiota and gut ecosystem during life and its influence on the host immunologic and metabolic phenotype are also analyzed to determine factors that affect aging-related diseases. Approaches to maintain host health and prevent or cure geriatric diseases are also discussed.

The Effect of Early-Life Environmental Exposures on Disease Phenotype and Clinical Course of Crohn's Disease in Children

OBJECTIVES

Environmental factors play an important role in the pathogenesis of Crohn's Disease (CD). In particular, by virtue of the instability of the microbiome and development of immunologic tolerance, early life factors may exert the strongest influence on disease risk and phenotype.

METHODS

We used data from 1119 CD subjects recruited from RISK inception cohort to examine the impact of early life environment on disease progression. Our primary exposures of interest were breastfeeding in infancy and exposure to maternal, active, or passive smoke. Our primary outcomes were development of complicated (stricturing or penetrating) disease, and need for CD-related hospitalization, and surgery. Multivariable logistic regression models were used to define independent associations, adjusting for relevant covariates.

RESULTS

Our study cohort included 1119 patients with CD among whom 15% had stricturing (B2) or penetrating disease (B3) by 3 years. 331 patients (35%) and 95 patients (10.6%) required CD-related hospitalizations and surgery respectively. 74.5% were breastfed in infancy and 31% were exposed to smoking among whom 7% were exposed to maternal smoke. On multivariable analysis, a history of breastfeeding was inversely associated with complicated (B2/B3 disease) 0.65, CI 95% 0.44-96; P = 0.03) in pediatric CD. Maternal smoking during pregnancy was associated with increased risk of hospitalization during the 3-year follow-up period (OR 1.75, CI 95% 1.05-2.89; P = 0.03).

CONCLUSIONS

Early life environmental factors influence the eventual phenotypes and disease course in CD.

Breast-feeding regulates immune system development via transforming growth factor-β in mice pups

BACKGROUND

Breast milk contains important nutrients and immunoregulatory factors that are essential for newborn infants. Recently, epidemiological studies suggested that breast-feeding prevents a wide range of infectious diseases and lowers the incidence of infant allergic diseases.

METHODS

To examine the effects of breast milk on immunological development in infancy, we established an artificial rearing system for hand-feeding mice and compared mouse pups fed with either breast milk or milk substitute. All mice were killed at 14 days of age and immune cells in the thymus, spleen, and small intestine were examined on flow cytometry.

RESULTS

The number of thymocytes was higher whereas that of total immune cells of peripheral lymphoid tissues was lower in mice fed breast milk compared with milk substitute-fed mice. In peripheral lymphoid tissues, the proportion of B cells was higher and that of CD8+ T cells, macrophages, dendritic cells, and granulocytes was significantly lower in breast milk-fed mice. The same alteration in immune cells of the thymus and peripheral lymphoid tissues in milk substitute-fed mice was also observed in pups reared by mother mice treated with anti-transforming growth factor-β (anti-TGF-β) monoclonal antibody.

CONCLUSIONS

Breast milk regulates the differentiation and expansion of innate and adaptive immune cells partly due to TGF-β. Hence, TGF-β in breast milk may be a new therapeutic target for innate immune system-mediated diseases of infancy.

Anticancer potential against cervix cancer (HeLa) cell line of probiotic Lactobacillus casei and Lactobacillus paracasei strains isolated from human breast milk

The CFCS of Lactobacilli strains from human breast milk induced apoptosis in HeLa cells ROS related mitochondrial pathway.

Systematic review with meta-analysis: breastfeeding and the risk of Crohn's disease and ulcerative colitis

BACKGROUND

Breastfeeding is a modifiable factor that may influence development of inflammatory bowel diseases. However, literature on this has been inconsistent and not accounted for heterogeneity in populations and exposure.

AIM

To conduct a meta-analysis to examine the association between breastfeeding in infancy and risk of Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

A systematic search of Medline/PubMed and Embase was performed for full text, English-language literature through November 2016. Studies were included if they described breastfeeding in infancy in patients with CD or UC, and healthy controls. Data were pooled using a random effects model for analysis.

RESULTS

A total of 35 studies were included in the final analysis, comprising 7536 individuals with CD, 7353 with UC and 330 222 controls. Ever being breastfed was associated with a lower risk of CD (OR 0.71, 95% CI 0.59-0.85) and UC (OR 0.78, 95% CI 0.67-0.91). While this inverse association was observed in all ethnicity groups, the magnitude of protection was significantly greater among Asians (OR 0.31, 95% CI 0.20-0.48) compared to Caucasians (OR 0.78, 95% CI 0.66-0.93; P = .0001) in CD. Breastfeeding duration showed a dose-dependent association, with strongest decrease in risk when breastfed for at least 12 months for CD (OR 0.20, 95% CI 0.08-0.50) and UC (OR 0.21, 95% CI 0.10-0.43) as compared to 3 or 6 months.

CONCLUSION

Breastfeeding in infancy protects against the development of CD and ulcerative colitis.

The Role of the Gut Microbiota in Bile Acid Metabolism

The gut microbiota has been considered a cornerstone of maintaining the health status of its human host because it not only facilitates harvesting of nutrients and energy from ingested food, but also produces numerous metabolites that can regulate host metabolism. One such class of metabolites, the bile acids, are synthesized from cholesterol in the liver and further metabolized by the gut microbiota into secondary bile acids. These bioconversions modulate the signaling properties of bile acids through the nuclear farnesoid X receptor and the G protein-coupled membrane receptor 5, which regulate diverse metabolic pathways in the host. In addition, bile acids can regulate gut microbial composition both directly and indirectly by activation of innate immune response genes in the small intestine. Therefore, host metabolism can be affected by both microbial modifications of bile acids, which leads to altered signaling via bile acid receptors, and by alterations in the composition of the microbiota. In this review, we mainly describe the interactions between bile acids and intestinal microbiota and their roles in regulating host metabolism, but we also examine the impact of bile acid composition in the gut on the intestinal microbiome and on host physiology.