The immunological components of human milk

Viruses and Human Milk: Transmission or Protection?

Human milk (HM) is considered the best source of nutrition for infant growth and health. This nourishment is unique and changes constantly during lactation to adapt to the physiological needs of the developing infant. It is also recognized as a potential route of transmission of some viral pathogens although the presence of a virus in HM rarely leads to a disease in an infant. This intriguing paradox can be explained by considering the intrinsic antiviral properties of HM. In this comprehensive and schematically presented review, we have described what viruses have been detected in HM so far and what their potential transmission risk through breastfeeding is. We have provided a description of all the antiviral compounds of HM, along with an analysis of their demonstrated and hypothesized mechanisms of action. Finally, we have also analyzed the impact of HM pasteurization and storage methods on the detection and transmission of viruses, and on the antiviral compounds of HM. We have highlighted that there is currently a deep knowledge on the potential transmission of viral pathogens through breastfeeding and on the antiviral properties of HM. The current evidence suggests that, in most cases, it is unnecessarily to deprive an infant of this high-quality nourishment and that the continuation of breastfeeding is in the best interest of the infant and the mother.

Breastfeeding continuation is associated with trait mindfulness but not with trajectories of postpartum depressive symptoms

OBJECTIVE

The WHO recommends breastfeeding for at least six months as breastfeeding has many benefits for both infant and mother. The association of breastfeeding continuation with trait mindfulness during pregnancy and trajectories of postpartum depressive symptoms has not been examined yet. The current study aimed to assess this association using cox regression analysis.

DESIGN, SETTING AND PARTICIPANTS

The current research is part of a large longitudinal prospective cohort study following women from 12 weeks of pregnancy onwards in the South-East part of the Netherlands.

MEASUREMENTS

A total of 698 participants filled out the Three Facet Mindfulness Questionnaire-Short Form (TFMQ-SF) at 22 weeks of pregnancy and completed both the Edinburgh Postnatal Depression Scale (EPDS) and questions on breastfeeding continuation one week, six weeks, four months, and eight months postpartum. Breastfeeding continuation was defined as exclusive breastfeeding or both breastfeeding and formula. The assessment eight months postpartum was used as a proxy for the WHO recommendation to continue breastfeeding for at least six months.

FINDINGS

Two trajectories (classes) of EPDS scores were determined using growth mixture modeling: 1) low stable (N = 631, 90.4%), and 2) increasing (N = 67, 9.6%). Cox regression analysis showed that the trait mindfulness facet non-reacting was significantly and inversely associated with the risk of breastfeeding discontinuation (HR = 0.96, 95% CI [0.94, 0.99], p = .002), while no significant association was found for belonging to the increasing EPDS class versus belonging to the low stable class (p = .735), adjusted for confounders.

KEY CONCLUSIONS

This study is the first to show that higher trait mindfulness non-reacting scores, but not persistently low levels of postpartum depressive symptoms, increase the likelihood of breastfeeding continuation.

IMPLICATIONS FOR PRACTICE

Improving non-reacting in perinatal women by meditation practice as part of a mindfulness-based intervention may lead to better breastfeeding continuation outcomes. Several mindfulness-based programs may be suitable.

The Association between Maternal Oral Inflammation and Neutrophil Phenotypes and Poly-Unsaturated Fatty Acids Composition in Human Milk: A Prospective Cohort Study

This prospective cohort study aimed to investigate the impact of maternal oral inflammation on human milk composition including neutrophil counts, activation state (based on cluster of differentiation (CD) markers expression), and fatty acid levels. Fifty mothers were recruited from St. Michael's hospital, Toronto, and followed up from 2-4 weeks until 4 months postpartum. Oral rinse and human milk samples were collected at both timepoints. Oral polymorphonuclear neutrophils (oPMNs) within the rinses were quantified using flow cytometry and the participants' oral health state was categorized into three groups (i.e., healthy, moderate, and severe) based on the oPMNs counts. Fatty acids were identified and quantified using a gas chromatography-flame ionization detector (GC-FID). Compared to mothers with a healthy oral health state, mothers with moderate to severe oral inflammation had a statistically significant decrease in the expression of CD64 biomarker, an increase in the expression of CD14 biomarker on human milk neutrophils and a decrease in the levels of eicosapentaenoic acid (C20:5n-3) in their human milk at follow-up compared to baseline. This study demonstrates for the first time that maternal oral inflammation can affect human milk composition. The mechanism by which these alterations can affect infant health outcomes in the long term critically needs to be considered.

Ultra-early weaning alters growth performance, hematology parameters, and fecal microbiota in piglets with same genetic background

Piglets with the same genetic background were used to investigate the effects of different lengths of suckling period on growth performance, hematology parameters, and fecal microbiota. All piglets were born by a sow (Landrace×Yorkshire). On day 14 postpartum, a total of 16 piglets [Duroc×(Landrace×Yorkshire)] with a similar initial body weight (2.48 ± 0.25 kg) were randomly assigned into two groups with four replicates per group, two pigs per replicate pen (one barrow and one gilt). On day 14 of age, experiment started, piglets from the first group were weaned (14W), whereas the others continued to receive milk until day 28 of age (28W). The experiment completed on day 70 of age, last 56 days. Growth performance parameters including body weight, average daily gain, feed intake, feed efficiency, and growth rate and hematology parameters including immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), albumin, globulin, and total protein were measured in this study. Additionally, a technique of 16S rRNA gene sequencing was used to analyze fecal microbiota for revealing how the changes in the lengths of suckling period on intestinal microbiota. We found that ultra-early weaning impaired growth performance of piglets, whose worse body weight, average daily gain, feed intake, feed efficiency, and growth rate were observed in 14W group at all measured timepoints in comparison with those in 28W group (P < 0.05). Moreover, higher contents of serum IgA (P = 0.028), IgG (P = 0.041), and IgM (P = 0.047), as well as lower contents of serum albumin (P = 0.002), albumin-to-globulin ratio (P = 0.003), and total protein (P = 0.004), were observed in 14W group in comparison with those in 28W group on day 28 of age, but not on day 70 of age. High-throughput pyrosequencing of 16S rRNA indicated that the intestinal microbiota richness in 14W group was lower than that in 28W group (P < 0.05); moreover, in comparison with 28W group at all sampling timepoints, fecal microbiota in 14W group showed more beneficial bacteria and fewer pathogenic bacteria (P < 0.05). Therefore, we considered that ultra-early weaning had positive effects on immune status and fecal microbiota composition in piglets, but negative effects on growth performance and fecal microbiota abundance.

Nutrition, Gut Microbiota, and Allergy Development in Infants

The process of gut microbiota development in infants is currently being challenged by numerous factors associated with the contemporary lifestyle, including diet. A thorough understanding of all aspects of microbiota development will be necessary for engineering strategies that can modulate it in a beneficial direction. The long-term consequences for human development and health of alterations in the succession pattern that forms the gut microbiota are just beginning to be explored and require much further investigation. Nevertheless, it is clear that gut microbiota development in infancy bears strong associations with the risk for allergic disease. A useful understanding of microbial succession in the gut of infants needs to reveal not only changes in taxonomic composition but also the development of functional capacities through time and how these are related to diet and various environmental factors. Metagenomic and metatranscriptomic studies have started to produce insights into the trends of functional repertoire and gene expression change within the first year after birth. This understanding is critical as during this period the most substantial development of the gut microbiota takes place and the relations between gut microbes and host immunity are established. However, further research needs to focus on the impact of diet on these changes and on how diet can be used to counteract the challenges posed by modern lifestyles to microbiota development and reduce the risk of allergic disease.

Efficacy of Donated Milk in Early Nutrition of Preterm Infants: A Meta-Analysis

Background: Preterm birth is associated with an increased risk of many complications, which is a main public health problem worldwide with social and economic consequences. Human milk from breast feeding has been proved to be the optimal nutrition strategy for preterm infants when available. However, the lack of human milk from mothers makes formula widely used in clinical practice. In recent years, donated breast milk has gained popularity as an alternative choice which can provide human milk oligosaccharides and other bioactive substances. Objective: We aimed to conduct a systematic review and meta-analysis to evaluate the nutritional effects of donated breast milk on preterm infants compared with formula. Method: In the present study, we searched Medline, Web of Science, Embase, clinicaltrials.gov, the China national knowledge infrastructure, and the Cochrane central register of controlled trials for candidate randomized controlled trials (RCTs). Results: A total of 1390 patients were enrolled in 11 RCTs and meta-analysis results showed that donated breast milk is also more advantageous in reducing the incidence of necrotizing enterocolitis (NEC, RR = 0.67, 95% CI = 0.48 to 0.93, p = 0.02), reducing the duration of parenteral nutrition (MD = −2.39, 95% CI = −3.66 to −1.13, p = 0.0002) and the time of full enteral feeding (MD = −0.33, 95% CI = −3.23 to 2.57, p = 0.0002). In comparison, formula significantly promotes the growth of premature infants, including their weight gain (MD = −3.45, 95% CI = −3.68 to −3.21, p < 0.00001), head growth (MD = −0.07, 95% CI = −0.08 to −0.06, p < 0.00001) and body length (MD = −0.13, 95% CI = −0.15 to −0.11, p < 0.00001), and reduces the time it takes for premature infants to regain birth weight (MD = 6.60, 95% CI = 6.11 to 7.08, p < 0.00001. Conclusion: Compared with formula, donated breast milk could significantly reduce the incidence of NEC, the duration of parenteral nutrition, and the time of full enteral feeding. Adding fortifiers in donated milk could make it as effective as formula in promoting the physical growth of premature infants.

Maternal Vitamin D Status Correlates to Leukocyte Antigenic Responses in Breastfeeding Infants

It is unknown if vitamin D (vitD) sufficiency in breastfeeding mothers can lead to physiological outcomes for their children that are discernible from infant vitD sufficiency per se. In a 3-month, randomized vitD supplementation study of mothers and their exclusively breastfeeding infants, the effects of maternal vitD sufficiency were determined on infant plasma concentrations of 25-hydroxyvitamin D (i.e., vitD status) and 11 cytokines. An inverse correlation was seen between maternal vitD status and infant plasma TNF concentration (r = −0.27; p < 0.05). Infant whole blood was also subjected to in vitro antigenic stimulation. TNF, IFNγ, IL-4, IL-13, and TGFβ1 responses by infant leukocytes were significantly higher if mothers were vitD sufficient but were not as closely correlated to infants’ own vitD status. Conversely, IL-10 and IL-12 responses after antigenic challenge were more correlated to infant vitD status. These data are consistent with vitD-mediated changes in breast milk composition providing immunological signaling to breastfeeding infants and indicate differential physiological effects of direct-infant versus maternal vitD supplementation. Thus, consistent with many previous studies that focused on the importance of vitD sufficiency during pregnancy, maintenance of maternal sufficiency likely continues to affect the health of breastfed infants.

Breastmilk, Stool, and Meconium: Bacterial Communities in South Africa

Human milk optimizes gut microbial richness and diversity, and is critical for proper immune development. Research has shown differing microbial composition based on geographic location, providing evidence that diverse biospecimen data is needed when studying human bacterial communities. Yet, limited research describes human milk and infant gut microbial communities in Africa. Our study uses breastmilk, stool, and meconium samples from a South African birth cohort to describe the microbial diversity, identify distinct taxonomic units, and determine correlations between bacterial abundance in breastmilk and stool samples. Mother-infant dyads (N = 20) were identified from a longitudinal birth cohort in the Vhembe district of Limpopo Province, South Africa. Breastmilk, meconium, and stool samples were analyzed using 16S ribosomal RNA sequencing of the V4-V5 gene region using the MiSeq platform for identification and relative quantification of bacterial taxa. A non-metric multidimensional scaling using Bray-Curtis distances of sample Z-scores showed that meconium, stool, and breastmilk microbial communities are distinct with varying genus. Breastmilk was mostly comprised of Streptococcus, Staphylococcus, Veillonella, and Corynebacterium. Stool samples showed the highest levels of Bifidobacterium, Faecalibacterium, Bacteroides, and Streptococcus. Alpha diversity measures found that stool samples have the highest Shannon index score compared to breastmilk and meconium. The abundance of Bifidobacterium (r = 0.57), Blautia (r = 0.59), and Haemophilus (r = 0.69) was correlated (p < 0.1) between breastmilk and stool samples. Despite the importance of breastmilk in seeding the infant gut microbiome, we found evidence of distinct bacterial communities between breastmilk and stool samples from South African mother-infant dyads.

OUP accepted manuscript

The intestinal microbiota plays a crucial role in health and changes in its composition are linked with major global human diseases. Fully understanding what shapes the human intestinal microbiota composition and knowing ways of modulating the composition are critical for promotion of life-course health, combating diseases, and reducing global health disparities. We aim to provide a foundation for understanding what shapes the human intestinal microbiota on an individual and global scale, and how interventions could utilize this information to promote life-course health and reduce global health disparities. We briefly review experiences within the first 1,000 days of life and how long-term exposures to environmental elements or geographic specific cultures have lasting impacts on the intestinal microbiota. We also discuss major public health threats linked to the intestinal microbiota, including antimicrobial resistance and disappearing microbial diversity due to globalization. In order to promote global health, we argue that the interplay of the larger ecosystem with intestinal microbiota research should be utilized for future research and urge for global efforts to conserve microbial diversity.

Natural Biomaterials from Biodiversity for Healthcare Applications

Natural biomaterials originating during the growth cycles of all living organisms have been used for many applications. They span from bioinert to bioactive materials including bioinspired ones. As they exhibit an increasing degree of sophistication, natural biomaterials have proven suitable to address the needs of the healthcare sector. Here the different natural healthcare biomaterials, their biodiversity sources, properties, and promising healthcare applications are reviewed. The variability of their properties as a result of considered species and their habitat is also discussed. Finally, some limitations of natural biomaterials are discussed and possible future developments are provided as more natural biomaterials are yet to be discovered and studied.

Associations between Feeding Patterns and Infant Health in China: A Propensity Score Matching Approach

Breastmilk is the optimal food for infants. Feeding pattern is closely related to physical development and health during infancy. Understanding the associations between feeding patterns and health status can inform related policy interventions and advocacy in China. This study aimed to investigate the relationship between infant feeding patterns and health status in China infants. The China National Nutrition and Health Surveillance 2013 was a national-representative cross-sectional study performed particularly for children aged 0-5 years. A total of 3974 infants aged under 1 year were included in the analysis, of whom 1082 (27.2%) made up the formula feeding group, and 2892 (72.8%) made up the breastfeeding group. The associations between feeding patterns and physical development and health were investigated using propensity score matching and multivariable logistic regression models. Among breastfeeding and formula feeding infants aged 9-11 months old, weight-for-age z score was 1.1 ± 1.1 and 0.9 ± 1.3, respectively, and weight-for-length z score was 1.0 ± 1.3 and 0.7 ± 1.4, respectively. Hemoglobin in 0-2, 3-5, 6-8, and 9-11 months old breastfeeding infants was 121.4 ± 15.2 g/L, 117.1 ± 13.0 g/L, 113. 9 ± 11.9 g/L, and 114.4 ± 14.0 g/L, while in 0-2, 3-5, 6-8, and 9-11 months formula feeding infants was 116.3 ± 14.8 g/L, 120.4 ± 11.3 g/L, 119.8 ± 11.2 g/L, and 120.0 ± 11.5 g/L, respectively. Breastfeeding was associated with lower risk of respiratory disease (OR: 0.79; 95% CI: 0.64, 0.99) and diarrhea (OR: 0.75; 95% CI: 0.57, 0.98). Breastfeeding could slightly improve infant physical development, and had a protective effect on the diarrheal and respiratory diseases. Infants aged 3-11 months who were breastfeeding showed lower hemoglobin than that of formula-fed infants and thus should increase intake of iron rich complementary foods.

Long Chain Polyunsaturated Fatty Acids Docosahexaenoic Acid and Arachidonic Acid Supplementation in the Suckling and the Post-weaning Diet Influences the Immune System Development of T Helper Type-2 Bias Brown Norway Rat Offspring

Background: Dietary long chain polyunsaturated fatty acids (LCPUFA) such as arachidonic acid (ARA) and docosahexaenoic acid (DHA) play an important role in the development of the infant immune system. The role of LCPUFA in the T helper type 2 (Th2) biased immune system is unknown. We aimed to understand the effect of feeding LCPUFA during suckling and post-weaning on immune system development in Th2 bias Brown Norway rat offspring.

Methods: Brown Norway dams were randomly assigned to nutritionally adequate maternal diet throughout the suckling period (0–3 weeks), namely, control diet (0% ARA, 0% DHA; n= 8) or ARA + DHA (0.45% ARA, 0.8% DHA; n = 10). At 3 weeks, offspring from each maternal diet group were randomized to either a control (0% ARA, 0% DHA; n = 19) or ARA+DHA post-weaning (0.5% ARA, 0.5% DHA; n = 18) diet. At 8 weeks, offspring were killed, and tissues were collected for immune cell function and fatty acid composition analyses.

Results: ARA + DHA maternal diet resulted in higher (p < 0.05) DHA composition in breast milk (4×) without changing ARA levels. This resulted in more mature adaptive immune cells in spleen [T regulatory (Treg) cells and B cells], mesenteric lymph nodes (MLN, lower CD45RA+), and Peyer's patches (PP; higher IgG+, B cells) in the ARA+DHA group offspring at 8 weeks. ARA+DHA post-weaning diet (3–8 weeks) resulted in 2 × higher DHA in splenocyte phospholipids compared to control. This also resulted in higher Th1 cytokines, ~50% higher TNF-α and IFNγ, by PMAi stimulated splenocytes ex vivo, with no differences in Th2 cytokines (IL-4, IL-13, and IL-10) compared to controls.

Conclusion: Feeding dams a diet higher in DHA during the suckling period resulted in adaptive immune cell maturation in offspring at 8 weeks. Providing ARA and DHA during the post-weaning period in a Th2 biased Brown Norway offspring model may support Th1 biased immune response development, which could be associated with a lower risk of developing atopic diseases.

Osteopontin Levels in Human Milk Are Related to Maternal Nutrition and Infant Health and Growth

Background: Osteopontin (OPN) is a glycosylated phosphoprotein found in human tissues and body fluids. OPN in breast milk is thought to play a major role in growth and immune system development in early infancy. Here, we investigated maternal factors that may affect concentrations of OPN in breast milk, and the possible associated consequences for the health of neonates. Methods: General characteristics, health status, dietary patterns, and anthropometric measurements of 85 mothers and their babies were recorded antenatally and during postnatal follow-up. Results: The mean concentration of OPN in breast milk was 137.1 ± 56.8 mg/L. Maternal factors including smoking, BMI, birth route, pregnancy weight gain, and energy intake during lactation were associated with OPN levels (p < 0.05). Significant correlations were determined between body weight, length, and head circumference, respectively, and OPN levels after one (r = 0.442, p = < 0.001; r = −0.284, p = < 0.001; r = −0.392, p = < 0.001) and three months (r = 0.501, p = < 0.001; r = −0.450, p = < 0.001; r = −0.498, p = < 0.001) of lactation. A negative relation between fever-related infant hospitalizations from 0–3 months and breast milk OPN levels (r = −0.599, p < 0.001) was identified. Conclusions: OPN concentrations in breast milk differ depending on maternal factors, and these differences can affect the growth and immune system functions of infants. OPN supplementation in infant formula feed may have benefits and should be further investigated.

Breastfeeding intention and trait mindfulness during pregnancy

OBJECTIVE

Breastfeeding has been associated with many health benefits for both infant and mother. Trait mindfulness during pregnancy may have a beneficial impact on breastfeeding intention. The current study aimed to examine whether trait mindfulness during pregnancy was associated with antenatal breastfeeding intention.

DESIGN, SETTING AND PARTICIPANTS

The current study is part of a large prospective population-based cohort study among pregnant women in the south of the Netherlands.

MEASUREMENTS

A subsample of participants completed the Three Facet Mindfulness Questionnaire-Short Form at 22 weeks of pregnancy and a question on their breastfeeding intention at 32 weeks of pregnancy (N=790). Moreover, the Edinburgh Depression Scale and Tilburg Pregnancy Distress scale were completed at 32 weeks of pregnancy to assess levels of distress.

FINDINGS

Univariate analyses showed that women with breastfeeding intention during pregnancy had significantly higher scores on the mindfulness facet non-reacting (p<.001, medium effect size) and significantly lower scores on acting with awareness (p=.035, small effect size). A subsequent multiple logistic regression analysis showed that only non-reacting remained significantly associated with antenatal breastfeeding intention (OR=1.09, 95% CI [1.03, 1.15], p=.001), after controlling for confounders. Women who eventually initiated breastfeeding had significantly higher non-reacting scores (p<.001, small to medium effect size).

KEY CONCLUSIONS

The mindfulness facet non-reacting was found to be associated with antenatal breastfeeding intention. More research is needed to confirm our results, since the current study is one of the first assessing the possible relation of trait mindfulness during pregnancy and breastfeeding intention.

IMPLICATIONS FOR PRACTICE

Mindfulness-based programs during pregnancy could be helpful in improving non-reacting in pregnant women, which may enhance breastfeeding intention and ultimately the initiation of breastfeeding.

Elaboration and psychometric analysis of a questionnaire to evaluate the knowledge of community health workers about breastfeeding

Abstract Objectives: to develop and analyze the psychometric properties of a questionnaire to assess community health workers’ knowledge on breastfeeding. Methods: this is a methodological study for the development of an instrument and analysis of validity and reliability. For the elaboration of items and identification of dimensions, a literature review was conducted. The items were submitted to the evaluation of a committee of judges, for apparent and content analysis. Construct validation was conducted through hypothesis test, with the participation of 282 community health workers and 19 pediatricians and obstetric nurses. For analysis and comparison of scores, the Mann-Whitney U test was used, assuming a significance level of 5%. Reliability was assessed using Cronbach's alpha coefficient and temporal consistency of the instrument was assessed using test-retest and Kappa analysis. Results: the final instrument presented a favorable opinion from the committee of judges. The hypothesis test showed that the questionnaire has discriminatory power to assess professionals with a higher level of knowledge (p<0.001). The Kappa test revealed that 63% of the items showed substantive to almost perfect agreement. The 32-item questionnaire showed a Cronbach's alpha of 0.794. Conclusion: the instrument developed was valid and reliable, allowing effective measurement of community health workers’ knowledge on breastfeeding.

Rat Milk and Plasma Immunological Profile throughout Lactation

The composition of bioactive factors with immune activity in human breast milk is widely studied. However, the knowledge on rat milk immune factors during the whole lactation period is still scarce. This study aimed to analyze rat breast milk’s immunoglobulin (Ig) content and some critical adipokines and growth factors throughout the lactation period, and to assess relationships with corresponding plasma levels. During lactation, milk concentration of the transforming growth factor (TGF)-β2 and -β3 showed a punctual increase in the first week, whereas adiponectin and leptin remained stable. In the second period of lactation (d14–21), despite the increase in the milk epidermal growth factor (EGF), a decrease in fibroblast growth factor 21 (FGF21) was detected at day 21. Milk IgA concentration had a progressive increase during lactation, while no significant changes were found in IgM and IgG. Regarding plasma levels, a decrease in all studied adipokines was observed in the second period of lactation, with the exception of IgA and TGF-β1, which reached their highest values at the end of the study. A positive correlation in IgM, IgG, and adipokine concentration was detected between milk and plasma compartments. In summary, the changes in the pattern of these bioactive compounds in rat milk and plasma and their relationships during lactation are established.

Suckling by Schistosoma mansoni-infected mothers restored IgG2a and TGF-β production, but not IL-6 and delayed-type hypersensitivity in IL-12/IL-23-deficient mice

INTRODUCTION

Suckling by schistosomotic mice improves anti-ovalbumin (OA) antibody production, while delayed-type hypersensitivity (DTH) remains unaffected. This property of milk from schistosomotic mice was investigated in IL-12/IL-23-deficient mice (IL-12p40KO).

METHODS

We compared anti-OA DTH, IgG2a and cytokines in wild-type and IL-12p40KO mice suckled by infected (SIM) or non-infected (CONTROL) mothers.

RESULTS

SIM mice showed similar intensity and eosinophils in the DTH, which was abolished in IL-12p40KO and IL-12p40KO-SIM mice. In IL-12p40KO-SIM, IgG2a and TGF-β levels were higher, but IL-6 levels were lower.

CONCLUSIONS

Milk from schistosomotic mothers may evoke IgG2a without eliciting DTH in IL-12/IL-23 deficiencies, by changing TGF-β/IL-6 levels.

Host Defence Cryptides from Human Apolipoproteins: Applications in Medicinal Chemistry

Several eukaryotic proteins with defined physiological roles may act as precursors of cryptic bioactive peptides released upon protein cleavage by the host and/or bacterial proteases. Based on this, the term "cryptome" has been used to define the unique portion of the proteome encompassing proteins with the ability to generate bioactive peptides (cryptides) and proteins (crypteins) upon proteolytic cleavage. Hence, the cryptome represents a source of peptides with potential pharmacological interest. Among eukaryotic precursor proteins, human apolipoproteins play an important role, since promising bioactive peptides have been identified and characterized from apolipoproteins E, B, and A-I sequences. Human apolipoproteins derived peptides have been shown to exhibit antibacterial, anti-biofilm, antiviral, anti-inflammatory, anti-atherogenic, antioxidant, or anticancer activities in in vitro assays and, in some cases, also in in vivo experiments on animal models. The most interesting Host Defence Peptides (HDPs) identified thus far in human apolipoproteins are described here with a focus on their biological activities applicable to biomedicine. Altogether, reported evidence clearly indicates that cryptic peptides represent promising templates for the generation of new drugs and therapeutics against infectious diseases.

Maternal Transmission of SARS-CoV-2: Safety of Breastfeeding in Infants Born to Infected Mothers

Coronavirus disease 2019 (COVID-19) is a recent epidemic disease caused by severe acute respiratory syndrome virus type 2 (SARS-CoV-2). In pregnancy, SARS-Cov-2 infection creates additional alarm due to concerns regarding the potential for transmission from the mother to the baby during both the antenatal and postpartum times. In general, breastfeeding is seldom disallowed because of infection of the mother. However, there are few exceptions with regards to certain infectious organisms with established transmission evidence from mother to infant and the link of infection of a newborn with significant morbidity and mortality. It is confirmed that pregnant women can become infected with SARS-CoV-2, although the debate on the possible vertical transmission of SARS-CoV-2 infection during pregnancy is still open. In this regard, the literature is still poor. On the contrary, the information on the safety of breastfeeding even during infections seems reassuring when the mother takes the necessary precautions. However, there are still answered questions regarding the precautions to be taken during breastfeeding by COVID-19 patients. This paper reviews the existing answers to these and many other questions. This review therefore presents a summary of the present-day understanding of infection with SARS-CoV-2 and discusses the answers around the maternal transmission of COVID-19 and the potential threat of breastfeeding to babies born to infected pregnant mothers. In conclusion, intrauterine transmission of SARS-CoV-2 infection is less likely to occur during pregnancy. Most studies suggest that COVID-19 is not transmitted through breast milk. Correspondingly, COVID-19-infected neonates might acquire the infection via the respiratory route because of the postnatal contact with the mother rather than during the prenatal period. International organizations encourage breastfeeding regardless of the COVID-19 status of the mother or child as long as proper hygienic and safety measures are adhered to so as to minimize the chance of infant infection by droplets and direct contact with the infected mother. Pasteurized donor human milk or infant formula as supplemental feeding can be quite beneficial in the case of mother-infant separation till breastfeeding is safe.

Cow, Goat, and Mare Milk Diets Differentially Modulated the Immune System and Gut Microbiota of Mice Colonized by Healthy Infant Feces

Studies on the possible alternative supplements to breastmilk are gaining research interests. Although milk from cow, goat, and mare is nutritious, its effects on the relationship between the immune system, metabolites, and gut microbiota remain unclear. This study aimed to comprehensively evaluate the effects of cow, goat, and mare milk on the immune system, metabolites, and gut microbiota of mice colonized by healthy infant feces using human milk as a standard. We examined the serum biochemistry parameters, immunity indicators, T cells, gut microbiota abundance, and metabolites. Results showed that the impact of human milk on alanine transaminase, glutamic oxaloacetic transaminase, total protein, globulin, and glucose values was different from the cow, goat, and mare milk types. The effects of mare milk on the percentage of CD4⁺ T, Th1, Th2, Th17, and Treg cells, and the levels of IL-2, IL-4, sIgA, and d-lactic acid in the serum of the human microbiota-associated mice were comparable to those of human milk. Also, bacterial 16S rRNA gene sequence analysis revealed that human milk enriched the relative abundance of Akkermansia and Bacteroides, cow milk increased the relative abundance of Lactobacillus, goat milk increased the relative abundance of Escherichia-Shigella, and mare milk improved the relative abundance of Klebsiella. Besides, mare milk was similar to human milk in the concentration of the metabolites we analyzed. Our findings suggest that mare milk can positively modulate the gut microbiota and immunity status of infants and thus could be a possible replacement for human milk.

Human milk microbiota development during lactation and its relation to maternal geographic location and gestational hypertensive status

Bacteria in human milk could directly seed the infant intestinal microbiota, while information about how milk microbiota develops during lactation and how geographic location, gestational hypertensive status, and maternal age influence this process is limited. Here, we collected human milk samples from mothers of term infants at the first day, 2 weeks, and 6 weeks postpartum from 117 longitudinally followed-up mothers (age: 28.7 ± 3.6 y) recruited from three cities in China. We found that milk microbial diversity and richness were the highest in colostrum but gradually decreased over lactation. Microbial composition changed across lactation and exhibited more discrete compositional patterns in 2-week and 6-week milk samples compared with colostrum samples. At phylum level, the abundance of Proteobacteria increased during lactation, while Firmicutes showed the opposite trend. At genus level, Staphylococcus, Streptococcus, Acinetobacter, Pseudomonas, and Lactobacillus were predominant in colostrum samples and showed distinct variations across lactation. Maternal geographic location was significantly associated with the milk microbiota development and the abundance of predominant genus. In addition, milk from mothers with gestational prehypertension had a different and less diverse microbial community at genus level in early lactation times, and contained less Lactobacillus in the 2-week milk samples than those from normotensive mothers. Findings of our study outlined the human milk microbial diversity and community development over lactation, and underscored the importance of maternal geographic locations and gestational hypertensive status on milk microbiota, which might have important implications in the establishment of the infant intestinal microbiota via breastfeeding.

Immunomodulatory Constituents of Human Donor Milk

Mother's own human milk is the best nutrition for infants, especially preterm very-low-birth-weight (VLBW) (≤1,500 g) infants, because of its immune-modulatory constituents that strengthen the infant's host defense, provide protection against infections, and decrease the risk of necrotizing enterocolitis (NEC). When mother's own milk is unavailable or insufficient, donor human milk is considered the best alternative, especially for preterm VLBW infants. However, to assure biological safety, donor milk must be pasteurized. This results in partial or complete inactivation of some of the immunomodulatory constituents of human milk, which confer host defense. This review summarizes the current evidence regarding the effects of pasteurization on the different immunological constituents of donor milk, and their clinical significance, especially in relation to prevention of NEC.

Associations between infant and young child feeding practices and acute respiratory infection and diarrhoea in Ethiopia: A propensity score matching approach

BACKGROUND

Acute respiratory infection (ARI) and diarrhoea are the leading causes of childhood morbidity and mortality in Ethiopia. Understanding the associations between infant and young child feeding (IYCF) and ARI and diarrhoea can inform IYCF policy interventions and advocacy in Ethiopia. This study aimed to investigate the relationship between IYCF practices and ARI and diarrhoea in Ethiopian children.

METHODS

This study used the Ethiopia Demographic and Health Survey (EDHS) data for the years 2000 (n = 3680), 2005 (n = 3528), 2011 (n = 4037), and 2016 (n = 3861). The association between IYCF practices and (i) ARI and (ii) diarrhoea were investigated using propensity score matching and multivariable logistic regression models. The IYCF practices include early initiation of breastfeeding, exclusive breastfeeding (EBF), predominant breastfeeding, introduction of complementary foods, continued breastfeeding at two years and bottle feeding.

RESULTS

Infants and young children who were breastfed within 1-hour of birth and those who were exclusively breastfed had a lower prevalence of ARI. Infants who were exclusively and predominantly breastfed had a lower prevalence of diarrhoea. Early initiation of breastfeeding (Odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.72, 0.92) and EBF (OR: 0.65; 95% CI: 0.51, 0.83) were associated with lower risk of ARI. Bottle-fed children had higher odds of ARI (OR: 1.36; 95% CI: 1.10, 1.68). Early initiation of breastfeeding and EBF were associated with lower odds of diarrhoea (OR: 0.88; 95% CI: 0.79, 0.94 for Early initiation of breastfeeding and OR: 0.51; 95% CI: 0.39, 0.65 for EBF). Infants who were predominantly breastfed were less likely to experience diarrhoea (OR: 0.69; 95% CI: 0.53, 0.89).

CONCLUSION

The recommended best practices for preventing ARI and diarrhoeal diseases in infants and young children namely: the early initiation of breastfeeding, EBF and avoidance of bottle feeding should be institutionalized and scale-up in Ethiopia as part of implementation science approach to cover the know-do-gaps.

Whey milk proteomics from Schistosoma mansoni-infected mice reveals proteins involved in immunomodulation of the offspring

Milk from schistosomotic mothers can modulate the immune response of their offspring. However, its characterization and potential of modulating immunity has not yet been fully elucidated. Thus, the aim of this study was to evaluate whey proteins from the milk of Schistosoma mansoni-infected mice in order to identify the fractions which can act as potential immunomodulatory tools. For this, we did a mass spectrometry (nanoUPLC-MSE) analysis to characterize the proteomic profile of milk from infected (MIM) and non-infected mice (MNIM). It was possible to identify 29 differentially expressed proteins: 15 were only found in MIM, 10 only found in MNIM, and 4 were downregulated in MIM group. Gene Ontology (GO), pathway enrichment analysis, and protein-protein interaction (PPI) analyses indicated differentially expressed proteins linked to biological processes and pathways in MIM group such as the following: fructose 1,6-biphosphate metabolic and glycolytic processes, glucose metabolism, and neutrophil degranulation pathways. The downregulated and unique proteins identified in MNIM group were involved in the positive regulation of B cell activation and receptor signaling pathway, in the innate immune response, complement activation, and phagocytosis. The present findings revealed a protein profile that may be involved in the activation and deactivation of the offspring's immune system in the long term, conferring a protective character due to the previous contact with milk from infected mothers.

Gestation and breastfeeding in schistosomotic mice differentially alters the expression of histone deacetylases (HDACs) in adult offspring

BACKGROUND

Breastfeeding or gestation in schistosomotic mothers can cause long-term alterations in the immune response of offspring.

OBJECTIVES

Evaluate the expression of histone deacetylases (HDACs) (all classes), the production of cytokines by T and B lymphocytes and macrophages, and the frequency of CD4⁺CD25⁺FoxP3⁺-cells in adult offspring born and/or suckled by schistosomotic mothers.

METHODS

We harvested splenocytes from offspring born to (BIM), suckled by (SIM), or born to/suckled by (BSIM) schistosomotic mothers and animals from noninfected mothers (Control) at seven-weeks old and cultured them with/without Concanavalin A. HDAC expression was evaluated by real-time quantitative polymerase chain reaction (qPCR), and cytokines and membrane markers were evaluated by fluorescence-activated cell sorting (FACS).

FINDINGS

Compared to Control, BIM mice showed increased expression of HDAC9 and frequency of CD4⁺IL-10⁺-cells. The SIM group had increased expression of HDAC1, HDAC2, HDAC6, HDAC7, HDAC10, Sirt2, Sirt5, Sirt6, and Sirt7. The BSIM group only had increased HDAC10 expression. The SIM and BSIM groups exhibited decreased frequencies of CD4⁺IL-4⁺-cells and CD4⁺CD25⁺FoxP3⁺-cells, along with a higher frequency of CD14⁺IL-10⁺-cells and an increase in CD45R/B220⁺IL-10⁺-cells. The BSIM group also showed a high frequency of CD4⁺IL10⁺-cells.

MAIN CONCLUSIONS

Breastfeeding induced the expression of HDACs from various classes involved in reducing inflammatory responses. However, gestation enhanced the expression of a single HDAC and breastfeeding or gestation appears to favour multiple IL-10-dependent pathways, but not cells with a regulatory phenotype.

Neonatal Microbiome and Its Relationship to Necrotizing Enterocolitis: A Review of the Science

Necrotizing enterocolitis (NEC) occurs in many premature infants hospitalized in the neonatal intensive care unit. About 3% to 15% of very low-weight premature infants develop NEC, with an estimated 30% mortality rate for the cases requiring surgery. Currently, there is no known pathogenesis for NEC in the patient's populations. However, one of the most widely accepted hypotheses is having an abnormal fetal gut microbiome. The purpose of this review is to discuss some current methods of dysbiosis in the neonatal microbiome, such as maternal health, breastfeeding, and delivery method, and then to connect these to the occurrence of NEC in the infant and finally discuss some possibilities for limiting the occurrence of NEC in the future.

Breast Milk-Derived Extracellular Vesicles Enriched in Exosomes From Mothers With Type 1 Diabetes Contain Aberrant Levels of microRNAs

The breast milk plays a crucial role in shaping the initial intestinal microbiota and mucosal immunity of the infant. Interestingly, breastfeeding has proven to be protective against the early onset of immune-mediated diseases including type 1 diabetes. Studies have shown that exosomes from human breast milk are enriched in immune-modulating miRNAs suggesting that exosomal miRNAs (exomiRs) transferred to the infant could play a critical role in the development of the infant's immune system. We extracted exomiRs from breast milk of 52 lactating mothers (26 mothers with type 1 diabetes and 26 healthy mothers), to identify any differences in the exomiR content between the two groups. Small RNA-sequencing was performed to identify known and novel miRNAs in both groups. A total of 631 exomiRs were detected by small RNA sequencing including immune-related miRNAs such as hsa-let-7c, hsa-miR-21, hsa-miR-34a, hsa-miR-146b, and hsa-miR-200b. In addition, ~200 novel miRNAs were identified in both type 1 diabetes and control samples. Among the known miRNAs, nine exomiR's were found differentially expressed in mothers with type 1 diabetes compared to healthy mothers. The highly up-regulated miRNAs, hsa-miR-4497, and hsa-miR-3178, increased lipopolysaccharide-induced expression and secretion of tumor necrosis factor α (TNFα) in human monocytes. The up-regulated miRNA target genes were significantly enriched for longevity-regulating pathways and FoxO signaling. Our findings suggest a role of breast milk-derived exomiRs in modulating the infant's immune system.

The Function and Alteration of Immunological Properties in Human Milk of Obese Mothers

Maternal obesity is associated with metabolic changes in mothers and higher risk of obesity in the offspring. Obesity in breastfeeding mothers appears to influence human milk production as well as the quality of human milk. Maternal obesity is associated with alteration of immunological factors concentrations in the human milk, such as C-reactive protein (CRP), leptin, IL-6, insulin, TNF-Alpha, ghrelin, adiponectin, and obestatin. Human milk is considered a first choice for infant nutrition due to the complete profile of macro nutrients, micro nutrients, and immunological properties. It is essential to understand how maternal obesity influences immunological properties of human milk because alterations could impact the nutrition status and health of the infant. This review summarizes the literature regarding the impact of maternal obesity on the concentration of particular immunological properties in the human milk.

Enhancement of immune maturation in suckling rats by leptin and adiponectin supplementation

Leptin and adiponectin, adipokines present in breast milk, have shown immunomodulatory properties. The current study aimed to ascertain whether a nutritional supplementation with leptin or adiponectin in neonatal rats was able to influence the maturation of the systemic immune response in early life. To achieve this, suckling Wistar rats were supplemented with either leptin (0.7 μg/kg/day) or adiponectin (35 μg/kg/day) during the whole suckling period. Plasmatic immunoglobulins were quantified, and spleen lymphocyte composition and their ability to proliferate and release cytokines were evaluated during (day 14) and at the end (day 21) of the suckling period. Rats fed with either adipokine showed higher plasma IgM and IgG1 concentrations and adiponectin supplementation also increased IgG2a at both studied days (P < 0.05). With regard to the lymphocyte composition, both adipokine supplementations increased T cell proportion and both CD4⁺ and CD8⁺ T cell subsets after two weeks of supplementation (P < 0.05). Moreover, only leptin administration increased NK and NKT cell proportions at the end of the suckling period. Finally, both adipokines influenced the cytokine secretion pattern by splenocytes. In conclusion, these results suggest that leptin and adiponectin play a role in the maturation of the systemic immune response during the suckling period.

The immune response to sub-clinical mastitis is impaired in HIV-infected women

Background

Subclinical mastitis (SCM) is relatively common in lactating women and may be associated with HIV shedding in breast milk. The potential association between HIV infection and breast milk immunologic factors and immune response to SCM needs to be addressed.

Methods

In this cross-sectional study, SCM (Na/K ratio > 1) was tested in 165 mature breast milk samples collected from 40 HIV-infected women who didn’t transmit HIV to their child by breastfeeding and 43 HIV-uninfected women enrolled in an interventional cohort in South-Africa (Vertical Transmission Study). The level of 33 immune markers related to Th1/Th2 related response, inflammation and bacterial exposure were compared in ART-naive HIV-infected versus HIV-uninfected women. The associations between HIV infection and SCM on the concentration of immune factors were tested separately by Wilcoxon rank-sum test and corrected for false discovery rate. To control for potential confounder effects and take into account the clustering of breast milk samples from a single woman, multivariate mixed linear models adjusted on child age at the time of sampling were performed for each immune factor.

Results

Subclinical mastitis was detected in 15 (37.5%) HIV-infected women and 10 (23.3%) HIV-uninfected women. In the absence of SCM, the breast milk levels of IP-10 and MIG were higher and IL1-RA lower in HIV-infected women than in HIV-uninfected women (respectively p < 0.001, p = 0.001, p = 0.045). In HIV-uninfected women, SCM was characterized by a robust immune response with higher concentrations of a broad panel of Th1 and inflammatory related immune markers than in samples without SCM. By contrast, in HIV-infected women a limited number of immune markers were increased and lower increases were observed in samples with SCM than without SCM.

Conclusion

HIV infection in ART-naïve women was associated with elevated breast milk levels of IP-10 and MIG, which areTh1-related cytokines induced by IFN-γ. During SCM, a lower and narrower immune response was observed in HIV-infected than HIV-uninfected women, suggesting that HIV infection affects the capacity of the mammary gland to respond to SCM.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1667-4) contains supplementary material, which is available to authorized users.

Bovine milk derived skimmed milk powder and whey protein concentrate modulates Citrobacter rodentium shedding in the mouse intestinal tract

Skimmed milk powder (SMP) and whey protein concentrate (WPC) were manufactured from fresh milk collected from cows producing high or low Immunoglobulin (Ig) A levels in their milk. In addition commercial products were purchased for use as diluent or control treatments. A murine enteric disease model (Citrobacter rodentium) was used to assess whether delivery of selected bioactive molecules (IgA, IgG, Lactoferrin (Lf)) or formulation delivery matrix (SMP, WPC) affected faecal shedding of bacteria in C. rodentium infected mice. In trial one, faecal pellets collected from mice fed SMP containing IgA (0.007-0.35 mg/mL), IgG (0.28-0.58 mg/mL) and Lf (0.03-0.1 mg/mL) contained fewer C. rodentium (cfu) compared to control mice fed water (day 8, p < 0.04, analysis of variance (ANOVA) followed by Fisher's unprotected least significant difference (ULSD)). In trial two, WPC containing IgA (0.35-1.66 mg/mL), IgG (0.58-2.36 mg/mL) and Lf (0.02-0.45 mg/mL) did not affect C. rodentium shedding, but SMP again reduced faecal C. rodentium levels (day 12, p < 0.04, ANOVA followed by Fisher's ULSD). No C. rodentium was detected in sham phosphate-buffered saline inoculated mice. Mice fed a commercial WPC shed significantly greater numbers of C. rodentium over 4 consecutive days (Fishers ULSD test), compared to control mice fed water. These data indicate that SMP, but not WPC, modulates faecal shedding in C. rodentium-infected mice and may impact progression of C. rodentium infection independently of selected bioactive concentration. This suggests that food matrix can impact biological effects of foods.

Risk factors for periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome: a case-control study

The etiology and pathogenesis of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome are unclear. We performed a case-control study to evaluate potential environmental or lifestyle factors associated with PFAPA morbidity. We enrolled 119 patients with PFAPA syndrome who had undergone tonsillectomy in Oulu University Hospital between 1987 and 2007. We recruited 230 controls, matched for sex, birth date, and place from the database of the Population Register Center of Finland. All the patients and controls completed a questionnaire regarding exposure to environmental triggers during early childhood. Maternal smoking was more common among PFAPA syndrome patients than controls (23 vs. 14%; P = 0.005). PFAPA patients had lower breastfeeding rates than controls (94 vs. 99%; P = 0.006). No other environmental factors were associated with PFAPA syndrome, except having an aquarium at home (P = 0.007). The patient group also used natural or herbal medicines more often than the controls (P = 0.01).

CONCLUSION

Maternal smoking and lack of breastfeeding, known risk factors for common childhood infections, were more common in patients with PFAPA syndrome than in matched controls. Environmental factors may be important in the pathogenesis of PFAPA syndrome and should be evaluated in future studies. What is Known: • The pathogenesis and genetics of periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome remain unsolved. • PFAPA syndrome has been shown to cluster in families. What is New: • Maternal smoking and lack of breastfeeding are more common in patients with PFAPA syndrome than in the controls. • Environmental risk factors may be important in the pathogenesis of the syndrome.

Cryptides: latent peptides everywhere

Proteomic surveys with top-down platforms are today revealing thousands of naturally occurring fragments of bigger proteins. Some of them have not functional meaning because they derive from pathways responsible for protein degradation, but many have specific functions, often completely different from that one of the parent proteins. These peptides encrypted in the protein sequence are nowadays called cryptides. They are frequent in the animal and plant kingdoms and represent a new interesting -omic field of investigation. To point out how much widespread is their presence, we describe here the most studied cryptides from very common sources such as serum albumin, immunoglobulins, hemoglobin, and from saliva and milk proteins. Given its vastness, it is unfeasible to cover the topic exhaustively, therefore only several selected examples of cryptides from other sources are thereafter reported. Demanding is the development of new -omic platforms for the functional screening of new cryptides, which could provide suggestion for peptides and peptido-mimetics with variegate fields of application.

Breastfeeding and autoimmunity: Programing health from the beginning

Breast milk is not only a completely adapted nutrition source for the newborn but also an impressive array of immune-active molecules that afford protection against infections and shape mucosal immune responses. Decisive imprinting events might be modulated during the first months of life with potential health long-term effects, enhancing the importance of breastfeeding as a major influence on the immune system correct development and modifying disease susceptibility. The aim of this review was to clarify the link between breastfeeding and autoimmune diseases, inquiring the related mechanisms, based on data available in the literature. Being breastfed was associated with a lower incidence of diabetes, celiac disease, multiple sclerosis and asthma, explained by the protection against early infections, anti-inflammatory properties, antigen-specific tolerance induction, and regulation of infant's microbiome. The protective role of human milk in idiopathic juvenile arthritis, rheumatoid arthritis, and inflammatory bowel diseases remains controversial. On the other hand, the breastfeeding mother faces a health-challenging period in life. High levels of prolactin may lead either to the development of autoimmune diseases in susceptible mothers or exacerbations of current immune-mediated disorders. These features raise the question if mothers with autoimmune diseases, mainly systemic lupus erythematosus, should avoid breastfeeding.

Early life indicators predict mortality, illness, reduced welfare and carcass characteristics in finisher pigs

The objective of this study was to investigate associations between early life indicators, lactation management factors and subsequent mortality, health, welfare and carcass traits of offspring. A total of 1016 pigs from a batch born during one week were used. During lactation, number of liveborn piglets, stillborn and mummies, sow parity, number of times cross-fostered, weaning age, birth and weaning body weight (BW) were collected. Mortality was recorded throughout the offspring production cycle. Prior to slaughter, pigs were scored for lameness (1=non-lame to 3=severely lame). At slaughter, tail lesions were scored (0=no lesion to 4=severe lesion) and cold carcass weight (CCW), lean meat%, presence of pericarditis and heart condemnations were recorded. Additionally, lungs were scored for pleurisy (0=no lesions to 4=severely extended lesions) and enzootic pneumonia (EP) like lesions. There was an increased risk of lameness prior to slaughter for pigs born to first parity sows (P<0.05) compared with pigs born to older sows. Sow parity was a source of variation for cold carcass weight (P<0.05) and lean meat% (P<0.05). Pigs born in litters with more liveborn pigs were at greater risk of death and to be lame prior to slaughter (P<0.05). Pigs that were cross-fostered once were 11.69 times, and those that were cross-fostered ≥2 times were 7.28, times more likely to die compared with pigs that were not cross-fostered (P<0.05). Further, pigs that were cross-fostered once were at greater risk of pericarditis and heart condemnations compared with pigs that were not cross-fostered (P<0.05). Pigs with a birth BW of <0.95kg were at higher mortality risk throughout the production cycle. There was an increased risk of lameness, pleurisy, pericarditis and heart condemnations (P<0.05) for pigs with lower weaning weights. Additionally, heavier pigs at weaning also had higher carcass weights (P<0.05). There was an increased risk of lameness for pigs weaned at a younger age (P<0.05). Males were 2.27 times less likely to receive a score of zero for tail biting compared with female pigs. Results from this study highlight the complex relationship between management, performance and disease in pigs. They confirm that special attention should be given to lighter weight pigs and pigs born to first parity sows and that cross-fostering should be minimised.

Immune activation in lactating dams alters sucklings' brain cytokines and produces non-overlapping behavioral deficits in adult female and male offspring: A novel neurodevelopmental model of sex-specific psychopathology

Early immune activation (IA) in rodents, prenatal through the mother or early postnatal directly to the neonate, is widely used to produce behavioral endophenotypes relevant to schizophrenia and depression. Given that maternal immune response plays a crucial role in the deleterious effects of prenatal IA, and lactation is a critical vehicle of immunological support to the neonate, we predicted that immune activation of the lactating dam will produce long-term abnormalities in the sucklings. Nursing dams were injected on postnatal day 4 with the viral mimic poly-I:C (4mg/kg) or saline. Cytokine assessment was performed in dams' plasma and milk 2h, and in the sucklings' hippocampus, 6h and 24h following poly-I:C injection. Male and female sucklings were assessed in adulthood for: a) performance on behavioral tasks measuring constructs considered relevant to schizophrenia (selective attention and executive control) and depression (despair and anhedonia); b) response to relevant pharmacological treatments; c) brain structural changes. Maternal poly-I:C injection caused cytokine alterations in the dams' plasma and milk, as well as in the sucklings' hippocampus. Lactational poly-I:C exposure led to sex-dimorphic (non-overlapping) behavioral abnormalities in the adult offspring, with male but not female offspring exhibiting attentional and executive function abnormalities (manifested in persistent latent inhibition and slow reversal) and hypodopaminergia, and female but not male offspring exhibiting despair and anhedonia (manifested in increased immobility in the forced swim test and reduced saccharine preference) and hyperdopaminergia, mimicking the known sex-bias in schizophrenia and depression. The behavioral double-dissociation predicted distinct pharmacological profiles, recapitulating the pharmacology of negative/cognitive symptoms and depression. In-vivo imaging revealed hippocampal and striatal volume reductions in both sexes, as found in both disorders. This is the first evidence for the emergence of long-term behavioral and brain abnormalities after lactational exposure to an inflammatory agent, supporting a causal link between early immune activation and disrupted neuropsychodevelopment. That such exposure produces schizophrenia- or depression-like phenotype depending on sex, resonates with notions that risk factors are transdiagnostic, and that sex is a susceptibility factor for neurodevelopmental psychopathologies.

Infant Feeding and Risk of Type 1 Diabetes in Two Large Scandinavian Birth Cohorts

OBJECTIVE

Our aim was to study the relation between the duration of full and any breastfeeding and risk of type 1 diabetes.

RESEARCH DESIGN AND METHODS

We included two population-based cohorts of children followed from birth (1996-2009) to 2014 (Denmark) or 2015 (Norway). We analyzed data from a total of 155,392 children participating in the Norwegian Mother and Child Cohort Study (MoBa) and the Danish National Birth Cohort (DNBC). Parents reported infant dietary practices when their child was 6 and 18 months old. The outcome was clinical type 1 diabetes, ascertained from nationwide childhood diabetes registries. Hazard ratios (HRs) were estimated using Cox regression.

RESULTS

Type 1 diabetes was identified in 504 children during follow-up, and the incidence of type 1 diabetes per 100,000 person-years was 30.5 in the Norwegian cohort and 23.5 in the Danish cohort. Children who were never breastfed had a twofold increased risk of type 1 diabetes compared with those who were breastfed (HR 2.29 [95% CI 1.14-4.61] for no breastfeeding vs. any breastfeeding for ≥12 months). Among those who were breastfed, however, the incidence of type 1 diabetes was independent of duration of both full breastfeeding (HR per month 0.99 [95% CI 0.97-1.01]) and any breastfeeding (0.97 [0.92-1.03]).

CONCLUSIONS

Suggestive evidence supports the contention that breastfeeding reduces the risk of type 1 diabetes. Among those who were breastfed, however, no evidence indicated that prolonging full or any breastfeeding was associated with a reduced risk of type 1 diabetes.

The Importance of Human Milk for Immunity in Preterm Infants

The immune system of preterm infants is immature, placing them at increased risk for serious immune-related complications. Human milk provides a variety of immune protective and immune maturation factors that are beneficial to the preterm infant's poorly developed immune system. The most studied immune components in human milk include antimicrobial proteins, maternal leukocytes, immunoglobulins, cytokines and chemokines, oligosaccharides, gangliosides, nucleotides, and long-chain polyunsaturated fatty acids. There is growing evidence that these components contribute to the lower incidence of immune-related conditions in the preterm infant. Therefore, provision of these components in human milk, donor milk, or formula may provide immunologic benefits.

Qualitative and Quantitative Analyses of Glycogen in Human Milk

Identification as well as a detailed analysis of glycogen in human milk has not been shown yet. The present study confirmed that glycogen is contained in human milk by qualitative and quantitative analyses. High-performance anion exchange chromatography (HPAEC) and high-performance size exclusion chromatography with a multiangle laser light scattering detector (HPSEC-MALLS) were used for qualitative analysis of glycogen in human milk. Quantitative analysis was carried out by using samples obtained from the individual milks. The result revealed that the concentration of human milk glycogen varied depending on the mother's condition-such as the period postpartum and inflammation. The amounts of glycogen in human milk collected at 0 and 1-2 months postpartum were higher than in milk collected at 3-14 months postpartum. In the milk from mothers with severe mastitis, the concentration of glycogen was about 40 times higher than that in normal milk.

Breastfeeding and Adult Personality

Five Factor Model (FFM) personality traits are implicated in long-term health-risk behaviors and outcomes. Less research has addressed how early-life experiences are associated with individual differences in these traits in adulthood. We examine whether having been breastfed is associated with adult personality and well-being in the National Longitudinal Study of Adolescent to Adult Health. At Wave 1, caregivers reported whether the target child had been breastfed. At Wave 4, participants (N=13,113; 53% female; M_age=28.98) completed measures of psychological functioning. We tested for mean-level differences in the traits by breastfeeding status (yes/no) and by the duration of breastfeeding, controlling for basic demographic factors and early-life factors that could confound the breastfeeding-personality association (e.g., mother education). Participants who had been breastfed scored lower in neuroticism, anxiety, and hostility and higher in openness and optimism than those not breastfed. A curvilinear relation suggested that neuroticism was lowest for those breastfed for 9-12 months and highest for those either breastfed for >24 months or exclusively bottle-fed. Breastfeeding was unrelated to conscientiousness or state psychological functioning. This research suggests long-term psychological benefits to breastfeeding and indicates that early life experiences are associated with traits that are consequential for adult health.

Immunology of breast milk

Summary In the critical phase of immunological immaturity of the newborn, particularly for the immune system of mucous membranes, infants receive large amounts of bioactive components through colostrum and breast milk. Colostrum is the most potent natural immune booster known to science. Breastfeeding protects infants against infections mainly via secretory IgA (SIgA) antibodies, but also via other various bioactive factors. It is striking that the defense factors of human milk function without causing inflammation; some components are even anti-inflammatory. Protection against infections has been well evidenced during lactation against, e.g., acute and prolonged diarrhea, respiratory tract infections, including otitis media, urinary tract infection, neonatal septicemia, and necrotizing enterocolitis. The milk’s immunity content changes over time. In the early stages of lactation, IgA, anti-inflammatory factors and, more likely, immunologically active cells provide additional support for the immature immune system of the neonate. After this period, breast milk continues to adapt extraordinarily to the infant’s ontogeny and needs regarding immune protection and nutrition. The need to encourage breastfeeding is therefore justifiable, at least during the first 6 months of life, when the infant’s secretory IgA production is insignificant.

Atopic dermatitis prevention in children following maternal probiotic supplementation does not appear to be mediated by breast milk TSLP or TGF-β

Background

The Probiotics in Prevention of Allergy among Children in Trondheim (ProPACT) study, a randomised, placebo controlled trial, demonstrated that maternal supplementation with probiotic milk reduced the incidence of atopic dermatitis (AD) in infancy. The mechanisms behind this effect are incompletely understood and breast milk cytokines have been postulated as possible mediating factors. In this study we aimed to assess whether breast milk TLSP and TGF-β are affected by a maternal probiotic supplementation regime, and their contribution to the preventive effect of this regime on AD in the offspring.

Methods

TSLP and TGF-β isoforms (TGF-β₁, TGF-β₂ and TGF-β₃) were measured using ELISA and multiplex assays, respectively, in breast milk samples collected at 10 days and 3 months postpartum from women participating in the ProPACT trial (n = 259). The natural indirect and direct effects of maternal probiotics on AD, due to changes in breast milk cytokines, were estimated using causal mediation techniques.

Results

Probiotic supplementation tend to lead to high levels of breast milk TSLP at 10 days postpartum (p = 0.062), but this change did not contribute to the prevention of AD according to the mediation analysis. Probiotics had no apparent effect on TSLP at 3 months or TGF-βs at either time points. Thus, these are unlikely to be mediators of the effect of maternal probiotics on AD in offspring.

Conclusions

Whilst maternal probiotic supplementation resulted in higher breast milk concentrations of TLSP at 10 days postpartum, this does not appear to be a mechanism for prevention of AD by maternal probiotics.

Trial registration The original trial protocol is registered in ClinicalTrials.gov (identifier NCT00159523)

Evidence for the essentiality of arachidonic and docosahexaenoic acid in the postnatal maternal and infant diet for the development of the infant’s immune system early in life

Long-chain polyunsaturated fatty acids (LCPUFA), especially the balance between arachidonic (AA) and docosahexaenoic (DHA) acids are known to have important immunomodulatory roles during the postnatal period when the immune system is rapidly developing. AA and DHA are required in infant formula in many countries but are optional in North America. The rationale for adding these LCPUFA to full-term formula is based on their presence in breast milk and randomized controlled studies that suggest improved cognitive function in preterm infants, but results are more variable in full-term infants. Recently, the European Food Safety Authority has proposed, based on a lack of functional evidence, that AA is not required in infant formula for full-term infants during the first year of life but DHA should remain mandatory. The purpose of this review is to review the evidence from epidemiological and intervention studies regarding the essentiality of AA and DHA in the postnatal infant and maternal diet (breast-feeding) for the immune system development early in life. Although studies support the essentiality of DHA for the immune system development, more research is needed to rule out the essentiality of AA. Nevertheless, intervention studies have demonstrated improvement in many markers of immune function in infants fed formula supplemented with AA and DHA compared with unsupplemented formula, which appears to consistently result in beneficial health outcomes including reduction in the risk of developing allergic and atopic disease early in life.

Response on Pneumococcal Vaccine in Preterm Infants After Neutral and Acidic Oligosaccharides Supplementation

BACKGROUND

Supplementation of oligosaccharides in premature infants was shown to influence the immune system. We determined the effect of combined short-chain galacto-oligosaccharides (scGOS), long-chain fructo-oligosaccharides (lcFOS) and pectin-derived acidic oligosaccharides (pAOS) on antibody concentrations after pneumococcal conjugate vaccination in very preterm infants.

METHODS

Very preterm infants with gestational age <32 weeks and/or birth weight <1500 g were randomized to receive enteral supplementation with scGOS/lcFOS/pAOS or placebo between days 3 and 30 of life. Blood samples were collected at birth, 5 and 12 months of age and compared with term samples from a Dutch cross-sectional population-based serosurveillance study. IgG antibody levels to pneumococcal capsular polysaccharides were determined by multiplex immunoassay.

RESULTS

In total, 113 preterm infants were included with similar baseline and nutritional characteristics in both groups. After 3 primary pneumococcal vaccinations, the scGOS/lcFOS/pAOS-group had lower GMC antibody concentrations (µg/mL; serotype 4: 1.53, 6B:0.25, 9V: 1.19, 14: 2.39, 18C: 1.88, 19F: 7.42, 23F: 0.72) than the placebo group (serotype 4: 3.29, 6B: 0.79, 9V:2.64, 14: 4.52, 18C: 3.13, 19F: 14.64, 23F: 1.88; all P < 0.05), but comparable with those in the term control group (serotype 4: 0.97, 6B: 0.32, 9V: 1.67, 14: 3.24, 18C: 2.03, 19F: 5.06, 23F: 0.59; all P > 0.05). After the booster vaccination at 11 months, antibody levels were no longer different between the two preterm groups.

CONCLUSION

Enteral supplementation of scGOS/lcFOS/pAOS has a regulatory effect on the response to conjugated polysaccharide pneumococcal vaccine with normalization of the enhanced responses in preterm infants toward levels similar to healthy term infants.

The Role of Gluten in Celiac Disease and Type 1 Diabetes

Celiac disease (CD) and type 1 diabetes (T1D) are autoimmune conditions in which dietary gluten has been proven or suggested to play a pathogenic role. In CD; gluten is established as the instigator of autoimmunity; the autoimmune process is halted by removing gluten from the diet; which allows for resolution of celiac autoimmune enteropathy and subsequent normalization of serological markers of the disease. However; an analogous causative agent has not yet been identified for T1D. Nevertheless; the role of dietary gluten in development of T1D and the potentially beneficial effect of removing gluten from the diet of patients with T1D are still debated. In this review; we discuss the comorbid occurrence of CD and T1D and explore current evidences for the specific role of gluten in both conditions; specifically focusing on current evidence on the effect of gluten on the immune system and the gut microbiota.

Topical treatment with fresh human milk versus emollient on atopic eczema spots in young children: a small, randomized, split body, controlled, blinded pilot study

Background

Public health nurses report on effects of fresh human milk as treatment for conjunctivitis, rhinitis and atopic eczema (AE), the latter being highly prevalent in early childhood. Emollients and topical corticosteroids are first line treatment of AE. As many caregivers have steroid phobia, alternative treatment options for mild AE are of interest. The aim of this small pilot study was to assess the potential effects and risks of applying fresh human milk locally on eczema spots in children with AE.

Methods

This was a split body, controlled, randomized and physician blinded pilot study, of children with AE with two similar contralateral eczema spots having a mother breastfeeding the child or a sibling. Fresh expressed milk and emollient was applied on the intervention spot and emollient alone on the control area, three times a day for four weeks. The severity and area of the eczema spots was evaluated weekly, and samples from milk and the spots were analysed weekly with respect to bacterial colonisation.

Results

Of nine patients included, six completed the study. Mean age at inclusion was 18.5 months. The spots examined were localized on the arms, legs or cheeks. The spots were similar in severity, but differed in area. In one patient the eczema ceased after inclusion. In four patients both control and intervention areas increased during the intervention. The relative change in eczema area compared to baseline showed less increase in the intervention spots in two patients, whereas the opposite was observed in three. In four children Staphylococcus aureus was found in their eczema once or more. In three of the 28 human milk samples, Staphylococcus aureus, alfa haemolytic streptococci or coagulase negative staphylococci were detected. Staphylococcus aureus was found once both in human milk and in the eczema spots, no clinical signs of infection were however observed. No secondary infection due to milk application was detected.

Conclusion

In this small pilot study, no effect was found on eczema spots treated with topical application of fresh human milk. (ClinicalTrials.gov Identifier, NCT02381028).

Development of immunity in early life

The immune system in early life goes through rapid and radical changes. Early life is also the period with the highest risk of infections. The foetal immune system is programmed to coexist with foreign antigenic influences in utero, and postnatally to rapidly develop a functional system capable of distinguishing helpful microbes from harmful pathogens. Both host genetics and environmental influences shape this dramatic transition and direct the trajectory of the developing immune system into early childhood and beyond. Given the malleability of the immune system in early life, interventions aimed at modulating this trajectory thus have the potential to translate into considerable reductions in infectious disease burden with immediate as well as long-lasting benefit. However, an improved understanding of the underlying molecular drivers of early life immunity is prerequisite to optimise such interventions and transform the window of early life vulnerability into one of opportunity.