A Lipopolysaccharide-Enriched Cow's Milk Allergy Microbiome Promotes a TLR4-Dependent Proinflammatory Intestinal Immune Response.

We have previously reported that the gut microbiota of healthy infants harbors allergy-protective bacteria taxa that are depleted in infants with cow's milk allergy (CMA). Few reports have investigated the role of the gut microbiota in promoting allergic responses. In this study we selected a CMA-associated microbiota with increased abundance of Gram-negative bacteria for analysis of its proinflammatory potential. LPS is the major component of the outer membrane of Gram-negative bacteria. Colonization of mice with a global or conditional mutation of the LPS receptor TLR4 with this CMA microbiota induced expression of serum amyloid A1 (Saa1) and other Th17-, B cell-, and Th2-associated genes in the ileal epithelium in a TLR4-dependent manner. In agreement with the gene expression data, mice colonized with the CMA microbiota have expanded populations of Th17 and regulatory T cells and elevated concentrations of fecal IgA. Importantly, we used both antibiotic-treated specific pathogen-free and germ-free rederived mice with a conditional mutation of TLR4 in the CD11c+ compartment to demonstrate that the induction of proinflammatory genes, fecal IgA, and Th17 cells is dependent on TLR4 signaling. Furthermore, metagenomic sequencing revealed that the CMA microbiota has an increased abundance of LPS biosynthesis genes. Taken together, our results show that a microbiota displaying a higher abundance of LPS genes is associated with TLR4-dependent proinflammatory gene expression and a mixed type 2/type 3 response in mice, which may be characteristic of a subset of infants with CMA.

How dietary advanced glycation end products could facilitate the occurrence of food allergy.

BACKGROUND: Food allergy (FA) is one of the most common chronic conditions in children with an increasing prevalence facilitated by the exposure to environmental factors in predisposed individuals. It has been hypothesized that the increased consumption of ultra-processed foods, containing high levels of dietary advanced glycation end products (AGEs), could facilitate the occurrence of FA. OBJECTIVE: We sought to provide preclinical and clinical evidence on the potential role of AGEs in facilitating the occurrence of FA. METHODS: Human enterocytes, human small intestine organ culture, and PBMCs from children at risk for allergy were used to investigate the direct effect of AGEs on gut barrier, inflammation, TH2 cytokine response, and mitochondrial function. Intake of the 3 most common glycation products in Western diet foods, Nε-(carboxymethyl) lysine, Nε-(1-carboxyethyl) lysin, and Nδ-(5-hydro-5- methyl-4-imidazolone-2-yl)-ornithine (MG-H1), and the accumulation of AGEs in the skin were comparatively investigated in children with FA and in age-matched healthy controls. RESULTS: Human enterocytes exposed to AGEs showed alteration in gut barrier, AGE receptor expression, reactive oxygen species production, and autophagy, with increased transepithelial passage of food antigens. Small intestine organ cultures exposed to AGEs showed an increase of CD25+ cells and proliferating crypt enterocytes. PBMCs exposed to AGEs showed alteration in proliferation rate, AGE receptor activation, release of inflammatory and TH2 cytokines, and mitochondrial metabolism. Significant higher dietary AGE intake and skin accumulation were observed children with FA (n = 42) compared with age-matched healthy controls (n = 66). CONCLUSIONS: These data, supporting a potential role for dietary AGEs in facilitating the occurrence of FA, suggest the importance of limiting exposure to AGEs children as a potential preventive strategy against this common condition.

The chemistry of gut microbiome-derived lipopolysaccharides impacts on the occurrence of food allergy in the pediatric age.

Introduction: Food allergy (FA) in children is a major health concern. A better definition of the pathogenesis of the disease could facilitate effective preventive and therapeutic measures. Gut microbiome alterations could modulate the occurrence of FA, although the mechanisms involved in this phenomenon are poorly characterized. Gut bacteria release signaling byproducts from their cell wall, such as lipopolysaccharides (LPSs), which can act locally and systemically, modulating the immune system function. Methods: In the current study gut microbiome-derived LPS isolated from fecal samples of FA and healthy children was chemically characterized providing insights into the carbohydrate and lipid composition as well as into the LPS macromolecular nature. In addition, by means of a chemical/MALDI-TOF MS and MS/MS approach we elucidated the gut microbiome-derived lipid A mass spectral profile directly on fecal samples. Finally, we evaluated the pro-allergic and pro-tolerogenic potential of these fecal LPS and lipid A by harnessing peripheral blood mononuclear cells from healthy donors. Results: By analyzing fecal samples, we have identified different gut microbiome-derived LPS chemical features comparing FA children and healthy controls. We also have provided evidence on a different immunoregulatory action elicited by LPS on peripheral blood mononuclear cells collected from healthy donors suggesting that LPS from healthy individuals could be able to protect against the occurrence of FA, while LPS from children affected by FA could promote the allergic response. Discussion: Altogether these data highlight the relevance of gut microbiome-derived LPSs as potential biomarkers for FA and as a target of intervention to limit the disease burden.

Increased dietary intake of ultraprocessed foods and mitochondrial metabolism alterations in pediatric obesity.

The increased intake of ultraprocessed foods (UPFs) in the pediatric age paralleled with the risen prevalence of childhood obesity. The Ultraprocessed Foods in Obesity (UFO) Project aimed at investigating the potential mechanisms for the effects of UPFs in facilitating pediatric obesity, focusing on the direct role of advanced glycation end-products (AGEs) on mitochondrial function, the key regulator of obesity pathophysiology. We comparatively investigated the daily dietary intake of UPFs, energy, nutrients, dietary AGEs [Nε -(carboxymethyl)lysine (CML), Nε -(1-carboxyethyl)lysine (CEL), and Nδ -(5-hydro-5- methyl-4-imidazolon-2-yl)-ornithine (MG-H1)] in 53 obese patients and in 100 healthy controls visiting the Tertiary Center for Pediatric Nutrition of the Department of Translational Medical Science at the University of Naples "Federico II". AGEs skin accumulation and mitochondrial function in peripheral blood mononuclear cells (PBMCs) were also assessed. A higher intake of UPFs and AGEs, energy, protein, fat, and saturated fatty acids was observed in obese patients. Obese children presented significantly higher skin AGEs accumulation and alterations in mitochondrial metabolism. PBMCs from healthy controls exposed to AGEs showed the same mitochondrial alterations observed in patients. These findings support the UPFs role in pediatric obesity, and the need for dietary strategies limiting UPFs exposure for obesity prevention and treatment.

High Amylose Wheat Bread at Breakfast Increases Plasma Propionate Concentrations and Reduces the Postprandial Insulin Response to the Following Meal in Overweight Adults.

BACKGROUND: High amylose starchy foods modulate the postprandial metabolic response in humans. However, the mechanisms of their metabolic benefits and their impact on the subsequent meal have not been fully elucidated. OBJECTIVE: We aimed to evaluate whether glucose and insulin responses to a standard lunch are influenced by the consumption of amylose-rich bread at breakfast in overweight adults and whether changes in plasma short chain fatty acids (SCFAs) concentrations contribute to their metabolic effects. METHODS: Using a randomized crossover design, 11 men and 9 women, BMI 30 ± 3 kg/m2, 48 ± 19 y, consumed at breakfast 2 breads made with high amylose flour (HAF): 85%-HAF (180 g) and 75%-HAF (170 g), and control bread (120 g) containing 100% conventional flour. Plasma samples were collected at fasting, 4 h after breakfast, and 2 h after a standard lunch to measure glucose, insulin, and SCFA concentrations. ANOVA posthoc analyses were used for comparisons. RESULTS: Postprandial plasma glucose responses were 27% and 39% lower after breakfasts with 85%- and 70%-HAF breads than control bread (P = 0.026 and P = 0.003, respectively), with no difference after lunch. Insulin responses were not different between the 3 breakfasts, whereas there was a 28% lower response after the lunch following breakfast with 85%-HAF bread than the control (P = 0.049). Propionate concentrations increased from fasting by 9% and 12% 6 h after breakfasts with 85%- and 70%-HAF breads and decreased by 11% with control bread (P < 0.05). At 6 h after breakfast with 70%-HAF bread, plasma propionate and insulin were inversely correlated (r = -0.566; P = 0.044). CONCLUSIONS: Amylose-rich bread reduces the postprandial glucose response after breakfast and insulin concentrations after the subsequent lunch in overweight adults. This second meal effect may be mediated by the elevation of plasma propionate due to intestinal fermentation of resistant starch. High amylose products could be a promising tool in a dietary prevention strategy for type 2 diabetes. THIS TRIAL WAS REGISTERED AT CLINICAL TRIAL REGISTRY AS: NCT03899974 (https://www. CLINICALTRIALS: gov/ct2/show/NCT03899974).

Therapeutic Effects of Butyrate on Pediatric Obesity: A Randomized Clinical Trial.

Importance: The pediatric obesity disease burden imposes the necessity of new effective strategies. Objective: To determine whether oral butyrate supplementation as an adjunct to standard care is effective in the treatment of pediatric obesity. Design, Setting, and Participants: A randomized, quadruple-blind, placebo-controlled trial was performed from November 1, 2020, to December 31, 2021, at the Tertiary Center for Pediatric Nutrition, Department of Translational Medical Science, University of Naples Federico II, Naples, Italy. Participants included children aged 5 to 17 years with body mass index (BMI) greater than the 95th percentile. Interventions: Standard care for pediatric obesity supplemented with oral sodium butyrate, 20 mg/kg body weight per day, or placebo for 6 months was administered. Main Outcomes and Measures: The main outcome was the decrease of at least 0.25 BMI SD scores at 6 months. The secondary outcomes were changes in waist circumference; fasting glucose, insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, ghrelin, microRNA-221, and interleukin-6 levels; homeostatic model assessment of insulin resistance (HOMA-IR); dietary and lifestyle habits; and gut microbiome structure. Intention-to-treat analysis was conducted. Results: Fifty-four children with obesity (31 girls [57%], mean [SD] age, 11 [2.91] years) were randomized into the butyrate and placebo groups; 4 were lost to follow-up after receiving the intervention in the butyrate group and 2 in the placebo group. At intention-to-treat analysis (n = 54), children treated with butyrate had a higher rate of BMI decrease greater than or equal to 0.25 SD scores at 6 months (96% vs 56%, absolute benefit increase, 40%; 95% CI, 21% to 61%; P < .01). At per-protocol analysis (n = 48), the butyrate group showed the following changes as compared with the placebo group: waist circumference, -5.07 cm (95% CI, -7.68 to -2.46 cm; P < .001); insulin level, -5.41 µU/mL (95% CI, -10.49 to -0.34 µU/mL; P = .03); HOMA-IR, -1.14 (95% CI, -2.13 to -0.15; P = .02); ghrelin level, -47.89 µg/mL (95% CI, -91.80 to -3.98 µg/mL; P < .001); microRNA221 relative expression, -2.17 (95% CI, -3.35 to -0.99; P < .001); and IL-6 level, -4.81 pg/mL (95% CI, -7.74 to -1.88 pg/mL; P < .001). Similar patterns of adherence to standard care were observed in the 2 groups. Baseline gut microbiome signatures predictable of the therapeutic response were identified. Adverse effects included transient mild nausea and headache reported by 2 patients during the first month of butyrate intervention. Conclusions and Relevance: Oral butyrate supplementation may be effective in the treatment of pediatric obesity. Trial Registration: ClinicalTrials.gov Identifier: NCT04620057.

Effects of the Mediterranean Diet during pregnancy on the onset of allergy in at risk children: A study protocol of a multi-center, randomized- controlled, parallel groups, prospective trial (the PREMEDI study).

Introduction: Maternal diet during pregnancy has been linked to offspring allergy risk and it could represent a potential target for allergy prevention. The Mediterranean Diet (MD) is considered one of the healthiest dietary models. Randomized-controlled trials on the effect of MD in preventing pediatric allergic diseases are still needed. Methods and analysis: The Mediterranean Diet during Pregnancy study (PREMEDI) will be a 9-month multi-center, randomized-controlled, parallel groups, prospective trial. Healthy women (20-35 years) at their first trimester of pregnancy at risk for atopy baby, will be randomly allocated to Group 1 (standard obstetrical and gynecological follow-up and nutritional counseling to promote MD) or Group 2 (standard obstetrical and gynecological follow-up alone). 138 mother-child pair per group will be needed to detect a reduction in cumulative incidence of ≥1 allergic disease at 24 months of age. The primary study aim will be the evaluation of the occurrence of allergic disorders in the first 24 months of life. The secondary aims will be the evaluation of maternal weight gain, pregnancy/perinatal complications, growth indices and occurrence of other chronic disorders, mother-child pair adherence to MD and gut microbiome features, breastfeeding duration and breast milk composition, epigenetic modulation of genes involved in immune system, and metabolic pathways in the offspring. Ethics and dissemination: The study protocol has been approved by the Ethics Committee of the University of Naples Federico II (number 283/21) and it will be conducted in accordance with the Helsinki Declaration (Fortaleza revision, 2013), the Good Clinical Practice Standards (CPMP/ICH/135/95), the Italian Decree-Law 196/2003 regarding personal data and the European regulations on this subject. The study has been registered in the Clinical Trials Protocol Registration System. Clinical trial registration: [http://clinicaltrials.gov], identifier [NCT05119868].

Body growth assessment in children with IgE-mediated cow's milk protein allergy fed with a new amino acid-based formula.

Background: Amino acid-based formula (AAF) is a relevant dietary option for non-breastfed children. The present study was designed to evaluate the body growth pattern in cow's milk protein allergy (CMPA) children treated for 6 months with a new AAF. Methods: This was an open-label, single arm study evaluating body growth pattern in immunoglobulin E (IgE)-mediated CMPA infants receiving a new AAF for 6 months. The outcomes were anthropometry (weight, length, head circumference), adherence to the study formula and occurrence of adverse events (AEs). Results: Fifteen children [all Caucasian and born at term; 53.3% born with spontaneous delivery; 80% male; 80% with familial allergy risk; mean age (±SD) 3 ± 2.5 months at IgE-mediated CMPA diagnosis; mean age (±SD) 16.7 ± 5.9 months at enrolment, mean total serum IgE (±SD) 298.2 ± 200.4 kU/L] were included and completed the 6-month study. Data from fifteen age- and sex-matched healthy controls were also adopted as comparison. At baseline, all CMPA patients were weaned and were receiving the new AAF. All 15 patients completed the 6-month study period. For the entire CMPA pediatric patients' cohort, from baseline to the end of the study period, the body growth pattern resulted within the normal range of World Health Organization (WHO) growth references and resulted similar to healthy controls anthropometric values. The formula was well tolerated. The adherence was optimal and no AEs related to AAF use were reported. Conclusions: The new AAF ensured normal growth in subjects affected by IgE-mediated CMPA. This formula constitutes another suitable safe option for the management of pediatric patients affected by CMPA.

Therapeutic effects elicited by the probiotic Lacticaseibacillus rhamnosus GG in children with atopic dermatitis. The results of the ProPAD trial.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease affecting up to 20% of the pediatric population associated with alteration of skin and gut microbiome. Probiotics have been proposed for AD treatment. The ProPAD study aimed to investigate the therapeutic effects of the probiotic Lacticaseibacillus rhamnosus GG (LGG) in children with AD. METHODS: In total, 100 AD patients aged 6-36 months were enrolled in a randomized, double-blind, controlled trial to receive placebo (Group A) or LGG (1 x 1010 CFU/daily) (Group B) for 12 weeks. The primary outcome was the evaluation of the efficacy of LGG supplementation on AD severity comparing the Scoring Atopic Dermatitis (SCORAD) index at baseline (T0) and at 12-week (T12). A reduction of ≥8.7 points on the SCORAD index was considered as minimum clinically important difference (MCID). The secondary outcomes were the SCORAD index evaluation at 4-week (T16) after the end of LGG treatment, number of days without rescue medications, changes in Infant Dermatitis Quality Of Life questionnaire (IDQOL), gut microbiome structure and function, and skin microbiome structure. RESULTS: The rate of subjects achieving MCID at T12 and at T16 was higher in Group B (p < .05), and remained higher at T16 (p < .05)The number of days without rescue medications was higher in Group B. IDQOL improved at T12 in the Group B (p < .05). A beneficial modulation of gut and skin microbiome was observed only in Group B patients. CONCLUSIONS: The probiotic LGG could be useful as adjunctive therapy in pediatric AD. The beneficial effects on disease severity and quality of life paralleled with a beneficial modulation of gut and skin microbiome.

Protective effects of the postbiotic deriving from cow's milk fermentation with L. paracasei CBA L74 against Rotavirus infection in human enterocytes.

Rotavirus (RV) is the leading cause of acute gastroenteritis-associated mortality in early childhood. Emerging clinical evidence suggest the efficacy of the postbiotic approach based on cow's milk fermentation with the probiotic Lacticaseibacillus paracasei CBAL74 (FM-CBAL74) in preventing pediatric acute gastroenteritis, but the mechanisms of action are still poorly characterized. We evaluated the protective action of FM-CBAL74 in an in vitro model of RV infection in human enterocytes. The number of infected cells together with the relevant aspects of RV infection were assessed: epithelial barrier damage (tight-junction proteins and transepithelial electrical resistance evaluation), and inflammation (reactive oxygen species, pro-inflammatory cytokines IL-6, IL-8 and TNF-α, and mitogen-activated protein kinase pathway activation). Pre-incubation with FM-CBA L74 resulted in an inhibition of epithelial barrier damage and inflammation mediated by mitogen-activated protein kinase pathway activation induced by RV infection. Modulating several protective mechanisms, the postbiotic FM-CBAL74 exerted a preventive action against RV infection. This approach could be a disrupting nutritional strategy against one of the most common killers for the pediatric age.

A New Butyrate Releaser Exerts a Protective Action against SARS-CoV-2 Infection in Human Intestine.

Butyrate is a major gut microbiome metabolite that regulates several defense mechanisms against infectious diseases. Alterations in the gut microbiome, leading to reduced butyrate production, have been reported in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A new butyrate releaser, useful for all the known applications of butyrate, presenting physiochemical characteristics suitable for easy oral administration, (N-(1-carbamoyl-2-phenyl-ethyl) butyramide (FBA), has been recently developed. We investigated the protective action of FBA against SARS-CoV-2 infection in the human small intestine and enterocytes. Relevant aspects of SARS-CoV-2 infection were assessed: infectivity, host functional receptor angiotensin-converting enzyme-2 (ACE2), transmembrane protease serine 2 (TMPRSS2), neuropilin-1 (NRP1), pro-inflammatory cytokines expression, genes involved in the antiviral response and the activation of Nf-kB nuclear factor (erythroid-derived 2-like) 2 (Nfr2) pathways. We found that FBA positively modulates the crucial aspects of the infection in small intestinal biopsies and human enterocytes, reducing the expression of ACE2, TMPRSS2 and NRP1, pro-inflammatory cytokines interleukin (IL)-15, monocyte chemoattractant protein-1 (MCP-1) and TNF-α, and regulating several genes involved in antiviral pathways. FBA was also able to reduce the number of SARS-CoV-2-infected cells, and ACE2, TMPRSS2 and NRP1 expression. Lastly, through the inhibition of Nf-kB and the up-regulation of Nfr2, it was also able to reduce the expression of pro-inflammatory cytokines IL-15, MCP-1 and TNF-α in human enterocytes. The new butyrate releaser, FBA, exerts a preventive action against SARS-CoV-2 infection. It could be considered as an innovative strategy to limit COVID-19.

Corrigendum: Age-Related Differences in the Expression of Most Relevant Mediators of SARS-CoV-2 Infection in Human Respiratory and Gastrointestinal Tract.

[This corrects the article DOI: 10.3389/fped.2021.697390.].

Phenylalanine Butyramide Is a New Cosmetic Ingredient with Soothing and Anti-Reddening Potential.

Human skin is colonized by diverse commensal microbes, making up the skin microbiota (SM), contributing to skin integrity and homeostasis. Many of the beneficial effects aroused by the SM are exerted by microbial metabolites such as short-chain fatty acids (SCFAs), including butyric acid. The SCFAs can be used in cosmetic formulations against skin diseases to protect SM by preserving and/or restoring their natural balance. Unpleasant sensorial properties and unfavorable physico-chemical properties of butyrate strongly limit its cosmetic use. In contrast, some butyrate derivatives, including phenylalanine butyramide (C13H18N2O2, FBA), a solid form of butyric acid, are odorless while retaining the pharmacokinetic properties and safety profile of butyric acid. This study assessed the FBA's permeation across the skin and its soothing and anti-reddening potential to estimate its cosmetic application. The dosage method used to estimate FBA's levels was validated to be sure of analytical results. The FBA diffusion tests were estimated in vitro using a Franz-type vertical diffusion cell. The soothing action was evaluated in vivo by Colorimeter CL400, measuring the erythema index. The results suggest that the FBA represents an innovative way to exploit the benefits of butyric acid in the cosmetic fields since it cannot reach the bloodstream, is odorless, and has a significative soothing action (decrease the erythema index -15.7% after 30', and -17.8% after 60').

Protective effects elicited by cow milk fermented with L. Paracasei CBAL74 against SARS-CoV-2 infection in human enterocytes.

Fermented foods have been proposed in limiting SARS-CoV-2 infection. Emerging evidence suggest the efficacy of cow's milk fermented with the probiotic L. paracasei CBAL74 (FM-CBAL74) in preventing infectious diseases. We evaluated the protective action of FM-CBAL74 against SARS-CoV-2 infection in human enterocytes. Relevant aspects of SARS-CoV-2 infection were assessed: infectivity, host functional receptor angiotensin-converting enzyme-2 (ACE2), transmembrane protease serine 2 (TMPRSS2), and pro-inflammatory cytokines expression (IL-6, IL-15, IL-1ß, VEGFß, TNF-α, MCP-1, CXCL1). Pre-incubation with FM-CBA L74 reduced the number of infected cells. The expression of ACE2 and the pro-inflammatory cytokines IL-6, VEGFß, IL-15, IL-1ß was downregulated by the pre-treatment with this fermented food. No effect on TMPRSS2, MCP-1, TNF-α and CXCL1 expression was observed. Modulating the crucial aspects of the infection, the fermented food FM-CBAL74 exerts a preventive action against SARS-CoV-2. These evidence could pave the way to innovative nutritional strategy to mitigate the COVID-19.

Specific gut microbiome signatures and the associated pro-inflamatory functions are linked to pediatric allergy and acquisition of immune tolerance.

Understanding the functional potential of the gut microbiome is of primary importance for the design of innovative strategies for allergy treatment and prevention. Here we report the gut microbiome features of 90 children affected by food (FA) or respiratory (RA) allergies and 30 age-matched, healthy controls (CT). We identify specific microbial signatures in the gut microbiome of allergic children, such as higher abundance of Ruminococcus gnavus and Faecalibacterium prausnitzii, and a depletion of Bifidobacterium longum, Bacteroides dorei, B. vulgatus and fiber-degrading taxa. The metagenome of allergic children shows a pro-inflammatory potential, with an enrichment of genes involved in the production of bacterial lipo-polysaccharides and urease. We demonstrate that specific gut microbiome signatures at baseline can be predictable of immune tolerance acquisition. Finally, a strain-level selection occurring in the gut microbiome of allergic subjects is identified. R. gnavus strains enriched in FA and RA showed lower ability to degrade fiber, and genes involved in the production of a pro-inflammatory polysaccharide. We demonstrate that a gut microbiome dysbiosis occurs in allergic children, with R. gnavus emerging as a main player in pediatric allergy. These findings may open new strategies in the development of innovative preventive and therapeutic approaches. Trial: NCT04750980.

Age-Related Differences in the Expression of Most Relevant Mediators of SARS-CoV-2 Infection in Human Respiratory and Gastrointestinal Tract.

Background: Clinical features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection seem to differ in children compared to that in adults. It has been hypothesized that the lower clinical severity in children could be influenced by differential expression of the main host functional receptor to SARS-CoV-2, the angiotensin-converting enzyme 2 (ACE2), but data are still conflicting. To explore the origin of age-dependent clinical features of coronavirus disease 2019 (COVID-19), we comparatively evaluated the expression in children and adult subjects of the most relevant mediators of the SARS-CoV-2 infection: ACE2, angiotensin-converting enzyme 1 (ACE1), transmembrane serine protease-2 (TMPRSS2), and neuropilin-1 (NRP1), at upper respiratory tract and small intestine level. Methods: The expression of ACE2, ACE1, TMPRSS2, and NRP1 in nasal epithelium and in small intestine epithelium was investigated by quantitative real-time PCR analysis. Results: We found no differences in ACE2, ACE1, and TMPRSS2 expression in the nasal epithelium comparing children and adult subjects. In contrast, nasal epithelium NRP1 expression was lower in children compared to that in adults. Intestinal ACE2 expression was higher in children compared to that in adults, whereas intestinal ACE1 expression was higher in adults. Intestinal TMPRSS2 and NRP1 expression was similar comparing children and adult subjects. Conclusions: The lower severity of SARS-CoV-2 infection observed in children may be due to a different expression of nasal NRP1, that promotes the virus interaction with ACE2. However, the common findings of intestinal symptoms in children could be due to a higher expression of ACE2 at this level. The insights from these data will be useful in determining the treatment policies and preventive measures for COVID-19.

NGS Gene Panel Analysis Revealed Novel Mutations in Patients with Rare Congenital Diarrheal Disorders.

Congenital diarrheal disorders (CDDs) are early-onset enteropathies generally inherited as autosomal recessive traits. Most patients with CDDs require rapid diagnosis as they need immediate and specific therapy to avoid a poor prognosis, but their clinical picture is often overlapping with a myriad of nongenetic diarrheal diseases. We developed a next-generation sequencing (NGS) panel for the analysis of 92 CDD-related genes, by which we analyzed patients suspect for CDD, among which were (i) three patients with sucrose-isomaltase deficiency; (ii) four patients with microvillous inclusion disease; (iii) five patients with congenital tufting enteropathy; (iv) eight patients with glucose-galactose malabsorption; (v) five patients with congenital chloride diarrhea. In all cases, we identified the mutations in the disease-gene, among which were several novel mutations for which we defined pathogenicity using a combination of bioinformatic tools. Although CDDs are rare, all together, they have an incidence of about 1%. Considering that the clinical picture of these disorders is often confusing, a CDD-related multigene NGS panel contributes to unequivocal and rapid diagnosis, which also reduces the need for invasive procedures.

The Impact of Formula Choice for the Management of Pediatric Cow's Milk Allergy on the Occurrence of Other Allergic Manifestations: The Atopic March Cohort Study.

OBJECTIVES: To compare the impact of different formulas on the occurrence of other atopic manifestations and the time of immune tolerance acquisition. STUDY DESIGN: In a 36-month prospective cohort study, the occurrence of other atopic manifestations (eczema, urticaria, asthma, and rhinoconjunctivitis) and the time of immune tolerance acquisition were comparatively evaluated in immunoglobulin E-mediated children with cow's milk allergy (CMA) treated with extensively hydrolyzed casein formula containing the probiotic L. rhamnosus GG (EHCF + LGG), rice hydrolyzed formula, soy formula, extensively hydrolyzed whey formula (EHWF), or amino acid-based formula. RESULTS: In total, 365 subjects were enrolled into the study, 73 per formula cohort. The incidence of atopic manifestations was 0.22 (Bonferroni-corrected 95% CI 0.09-0.34) in the EHCF + LGG cohort; 0.52 (0.37-0.67) in the rice hydrolyzed formula cohort; 0.58 (0.43-0.72) in the soy formula cohort; 0.51 (0.36-0.66) in the EHWF cohort; and 0.77 (0.64-0.89) in the amino acid-based formula cohort. The incidence of atopic manifestations in the rice hydrolyzed formula, soy formula, EHWF, and amino acid-based formula cohorts vs the EHCF + LGG cohort was always greater than the prespecified absolute difference of 0.25 at an alpha-level of 0.0125, with corresponding risk ratios of 2.37 (1.46-3.86, P < .001) for rice hydrolyzed formula vs EHCF + LGG; 2.62 (1.63-4.22, P < .001) for soy formula vs EHCF + LGG; 2.31 (1.42-3.77, P < .001) for EHWF vs EHCF + LGG; and 3.50 (2.23-5.49, P < .001) for amino acid-based formula vs EHCF + LGG. The 36-month immune tolerance acquisition rate was greater in the EHCF + LGG cohort. CONCLUSIONS: The use of EHCF + LGG for CMA treatment is associated with lower incidence of atopic manifestations and greater rate of immune tolerance acquisition.

Potential Role of Omega-3 Polyunsaturated Fatty Acids in Pediatric Food Allergy.

Polyunsaturated fatty acids (PUFAs) are involved both in immune system regulation and inflammation. In particular, within the PUFAs category, omega-3 (ω-3) may reduce inflammation, whereas omega-6 (ω-6) PUFAs are generally considered to have a proinflammatory effect. Recent evidence highlights an imbalance in the ω-3:ω-6 ratio with an increased intake of ω-6, as a consequence of the shift towards a westernized diet. In critical age groups such as infants, toddlers and young children, as well as pregnant and lactating women or fish allergic patients, ω-3 intake may be inadequate. This review aims to discuss the potential beneficial effects of PUFAs on pediatric food allergy prevention and treatment, both at prenatal and postnatal ages. Data from preclinical studies with PUFAs supplementation show encouraging effects in suppressing allergic response. Clinical studies results are still conflicting about the best timing and dosages of supplementation and which individuals are most likely to benefit; therefore, it is still not possible to draw firm conclusions. With regard to food-allergic children, it is still debated whether PUFAs could slow disease progression or not, since consistent data are lacking. In conclusion, more data on the effects of ω-3 PUFAs supplementation alone or in combination with other nutrients are warranted, both in the general and food allergic population.