Immune Components in Human Milk Are Associated with Early Infant Immunological Health Outcomes: A Prospective Three-Country Analysis.

The role of breastfeeding in improving allergy outcomes in early childhood is still unclear. Evidence suggests that immune mediators in human milk (HM) play a critical role in infant immune maturation as well as protection against atopy/allergy development. We investigated relationships between levels of immune mediators in colostrum and mature milk and infant outcomes in the first year of life. In a large prospective study of 398 pregnant/lactating women in the United Kingdom, Russia and Italy, colostrum and mature human milk (HM) samples were analysed for immune active molecules. Statistical analyses used models adjusting for the site of collection, colostrum collection time, parity and maternal atopic status. Preliminary univariate analysis showed detectable interleukin (IL) 2 and IL13 in HM to be associated with less eczema. This finding was further confirmed in multivariate analysis, with detectable HM IL13 showing protective effect OR 0.18 (95% CI 0.04-0.92). In contrast, a higher risk of eczema was associated with higher HM concentrations of transforming growth factor ß (TGFß) 2 OR 1.04 (95% CI 1.01-1.06) per ng/mL. Parental-reported food allergy was reported less often when IL13 was detectable in colostrum OR 0.10 (95% CI 0.01-0.83). HM hepatocyte growth factor (HGF) was protective for common cold incidence at 12 months OR 0.19 (95% CI 0.04-0.92) per ng/mL. Data from this study suggests that differences in the individual immune composition of HM may have an influence on early life infant health outcomes. Increased TGFß2 levels in HM are associated with a higher incidence of reported eczema, with detectable IL13 in colostrum showing protective effects for food allergy and sensitization. HGF shows some protective effect on common cold incidence at one year of age. Future studies should be focused on maternal genotype, human milk microbiome and diet influence on human milk immune composition and both short- and long-term health outcomes in the infant.

Extensively hydrolyzed casein formula containing Lactobacillus rhamnosus GG reduces the occurrence of other allergic manifestations in children with cow's milk allergy: 3-year randomized controlled trial.

BACKGROUND: Children with cow's milk allergy (CMA) have an increased risk of other allergic manifestations (AMs). OBJECTIVE: We performed a parallel-arm randomized controlled trial to test whether administration of an extensively hydrolyzed casein formula (EHCF) containing the probiotic Lactobacillus rhamnosus GG (LGG) can reduce the occurrence of other AMs in children with CMA. METHODS: Children with IgE-mediated CMA were randomly allocated to the EHCF or EHCF+LGG groups and followed for 36 months. The main outcome was occurrence of at least 1 AM (eczema, urticaria, asthma, and rhinoconjunctivitis). The secondary outcome was tolerance acquisition, which was defined as the negativization of a double-blind food challenge results at 12, 24, and 36 months. AMs were diagnosed according to standardized criteria. Tolerance acquisition was evaluated every 12 months. RESULTS: A total of 220 children (147 boys [67%]) with a median age of 5.0 months (interquartile range, 3.0-8.0 months) were randomized; 110 children were placed in the EHCF group, and 110 children were placed in the EHCF+LGG group. In the complete case analysis the absolute risk difference for the occurrence of at least 1 AM over 36 months was -0.23 (95% CI, -0.36 to -0.10; P < .001), and the absolute risk difference for the acquisition of cow's milk tolerance was 0.20 (95% CI, 0.05-0.35; P < .01) at 12 months, 0.24 (95% CI, 0.08-0.41; P < .01) at 24 months, and 0.27 (95% CI, 0.11-0.43; P < .001) at 36 months. In the sensitivity analysis the effect size of the main outcome was virtually unchanged when the occurrence of AMs was assigned to all 27 missing children. CONCLUSIONS: EHCF+LGG reduces the incidence of other AMs and hastens the development of oral tolerance in children with IgE-mediated CMA.

Breast milk polyunsaturated fatty acids: associations with adolescent allergic disease and lung function.

BACKGROUND: It has been hypothesized that n-3 PUFA in breast milk may assist immune and lung development. There are very limited data on possible long-term effects on allergic disease and lung function. The aim was to investigate associations of n-3 and n-6 PUFA levels in colostrum and breast milk with allergic disease and lung function at ages 12 and 18 years. METHODS: Polyunsaturated fatty acids were measured in 194 colostrum samples and in 118 three-month expressed breast milk samples from mothers of children enrolled in the Melbourne Atopy Cohort (MACS) Study, a high-risk birth cohort study. Associations with allergic diseases, skin prick tests and lung function assessed at 12 and 18 years were estimated using multivariable regression. RESULTS: Higher levels of n-3 but not n-6 PUFAs in colostrum were associated with a trend towards increased odds of allergic diseases, with strong associations observed for allergic rhinitis at 12 (OR = 5.69[95% CI: 1.83,17.60] per weight%) and 18 years (4.43[1.46,13.39]) and eczema at 18 years (9.89[1.44, 68.49]). Higher levels of colostrum n-3 PUFAs were associated with reduced sensitization (3.37[1.18, 9.6]), mean FEV1 (-166 ml [-332, -1]) and FEV1 /FVC ratio (-4.6%, [-8.1, -1.1]) at 12 years. CONCLUSION: Higher levels of colostrum n-3 PUFAs were associated with increased risks of allergic rhinitis and eczema up to 18 years, and sensitization and reduced lung function at 12 years. As residual confounding may have caused these associations, they should be replicated, but these results could indicate that strategies that increase maternal n-3 PUFA intake may not aid in allergic disease prevention.

Probiotics for the prevention of allergy: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Allergic diseases are considered a health burden because of their high and constantly increasing prevalence, high direct and indirect costs, and undesirable effects on quality of life. Probiotics have been suggested as an intervention to prevent allergic diseases. OBJECTIVE: We sought to synthesize the evidence supporting use of probiotics for the prevention of allergies and inform World Allergy Organization guidelines on probiotic use. METHODS: We performed a systematic review of randomized trials assessing the effects of any probiotic administered to pregnant women, breast-feeding mothers, and/or infants. RESULTS: Of 2403 articles published until December 2014 identified in Cochrane Central Register of Controlled Trials, MEDLINE, and Embase, 29 studies fulfilled a priori specified inclusion criteria for the analyses. Probiotics reduced the risk of eczema when used by women during the last trimester of pregnancy (relative risk [RR], 0.71; 95% CI, 0.60-0.84), when used by breast-feeding mothers (RR, 0.57; 95% CI, 0.47-0.69), or when given to infants (RR, 0.80; 95% CI, 0.68-0.94). Evidence did not support an effect on other allergies, nutrition status, or incidence of adverse effects. The certainty in the evidence according to the Grading of Recommendation Assessment Development and Evaluation approach is low or very low because of the risk of bias, inconsistency and imprecision of results, and indirectness of available research. CONCLUSION: Probiotics used by pregnant women or breast-feeding mothers and/or given to infants reduced the risk of eczema in infants; however, the certainty in the evidence is low. No effect was observed for the prevention of other allergic conditions.

Exacerbation of atopic dermatitis on grass pollen exposure in an environmental challenge chamber.

BACKGROUND: It has frequently been speculated that pruritus and skin lesions develop after topical exposure to aeroallergens in sensitized patients with atopic dermatitis (AD). OBJECTIVE: We sought to study cutaneous reactions to grass pollen in adult patients with AD with accompanying clear IgE sensitization to grass allergen in an environmental challenge chamber using a monocenter, double-blind, placebo-controlled study design. METHODS: Subjects were challenged on 2 consecutive days with either 4000 pollen grains/m(3) of Dactylis glomerata pollen or clean air. The severity of AD was assessed at each study visit up to 5 days after challenge by (objective) scoring of AD (SCORAD). Additionally, air-exposed and non-air-exposed skin areas were each scored using local SCORAD scoring and investigator global assessments. Levels of a series of serum cytokines and chemokines were determined by using a Luminex-based immunoassay. The primary end point of the study was the change in objective SCORAD scores between prechallenge and postchallenge values. RESULTS: Exposure to grass pollen induced a significant worsening of AD. A pronounced eczema flare-up of air-exposed rather than covered skin areas occurred. In grass pollen-exposed subjects a significantly higher increase in CCL17, CCL22, and IL-4 serum levels was observed. CONCLUSIONS: This study demonstrates that controlled exposure to airborne allergens of patients with a so-called extrinsic IgE-mediated form of AD induced a worsening of cutaneous symptoms.

Serum Vitamin D levels and Vitamin D supplementation do not correlate with the severity of chronic eczema in children.

BACKGROUND: Eczema is one of the most common chronic inflammatory skin diseases, affecting about 20% of children. The pathogenic mechanisms of eczema are still not fully understood, and current treatment of moderate-severe eczema is often difficult. Recently, it has been suggested that Vitamin D plays a key role in this disease, even if mechanisms are only partially known. OBJECTIVE: The purpose of our study was to assess the 25-Hydroxyvitamin D serum levels in a pediatric population suffering from chronic eczema (IgE-mediated and non-IgE-mediated), and to correlate these phenotypes with the SCORAD severity and selected clinical and biological parameters. Moreover, we aimed to evaluate whether a supplementation of Vitamin D3 could affect the same clinical and laboratory parameters. METHODS: 89 children with chronic eczema were enrolled in the study. Severity of eczema was assessed with the SCORAD index. Past and present history was taken, and patients were divided into two groups according to the state of sensitization. According to a randomization schedule, the enrolled children were assigned to the following groups: supplementation group, which received a daily oral Vitamin D3 supplementation (2000 IUs) for 3 months; control group which received no supplementation. RESULTS: Vitamin D concentrations in patients with moderate and severe eczema were not statistically different from Vitamin D concentration detected in the serum of patients with mild eczema. Furthermore, we did not find any correlation between Vitamin D levels, total IgEs and SCORAD index, both in the Sensitized and in the Not-Sensitized group. The Vitamin D3 supplementation did not influence the SCORAD severity or the total IgEs concentration. CONCLUSION: To our knowledge, our study is the first one that shows no correlation between serum levels of Vitamin D, eczema severity and IgE sensitization in a pediatric population suffering from chronic eczema.

Differential effects of two probiotics on the risks of eczema and atopy associated with single nucleotide polymorphisms to Toll-like receptors.

BACKGROUND: There is strong evidence to support a genetic predisposition to eczema and more recently studies have suggested that probiotics might be used to prevent eczema by modifying the expression of putative allergy-associated genes. The aim of this present study was to investigate whether two probiotics, Lactobacillus rhamnosus HN001 (HN001) and Bifidobacterium animalis subsp. lactis HN019 (HN019), can modify the known genetic predisposition to eczema conferred by genetic variation in the Toll-like receptor (TLR) genes in a high-risk infant population. METHODS: We selected 54 SNPs in the Toll-like receptor genes. These SNPs were analysed in 331 children of sole European ancestry as part of a double-blind, randomized, placebo-controlled trial examining the effects of HN001 and HN019 supplementation on eczema development and atopic sensitization. RESULTS: The data showed that 26 TLR SNPs interacted with HN001 resulting in a significantly reduced risk of eczema, 18 for eczema severity as defined by SCORAD ≥ 10 and 20 for atopic sensitization compared to placebo. There were only two SNPs that interacted with HN019 resulting in a reduced risk of eczema, eczema severity or atopy. CONCLUSIONS: This is the first study to show that the negative impact of specific TLR genotypes may be positively affected by probiotic supplementation. HN001 exhibits a much stronger effect than HN019 in this respect.

Update on the immunological mechanism of action behind phototherapy.

Phototherapy is often used to treat inflammatory skin conditions such as psoriasis and eczema. Much progress has recently been made in understanding the mechanisms underlying the local, cutaneous immune effects induced by phototherapy. Unlike many immunosuppressive drugs used in the management of inflammatory skin disease, phototherapy not only targets effector immune cells but also appears to up-regulate regulatory T cells (Tregs). Additionally, phototherapy reverses epidermal barrier abnormalities common in these diseases, allowing for restoration of cutaneous homeostasis.

Randomized controlled trial of fish oil supplementation in pregnancy on childhood allergies.

BACKGROUND: Diets high in n-3 long chain polyunsaturated fatty acids (LCPUFA) may modulate the development of IgE-mediated allergic disease and have been proposed as a possible allergy prevention strategy. The aim of this study was to determine whether n-3 LCPUFA supplementation of pregnant women reduces IgE-mediated allergic disease in their children. METHODS: Follow-up of children (n = 706) at hereditary risk of allergic disease in the Docosahexaenoic Acid to Optimise Mother Infant Outcome randomized controlled trial. The intervention group (n = 368) was randomly allocated to receive fish oil capsules (providing 900 mg of n-3 LCPUFA daily) from 21 weeks' gestation until birth; the control group (n = 338) received matched vegetable oil capsules without n-3 LCPUFA. The diagnosis of allergic disease was made during medical assessments at 1 and 3 years of age. RESULTS: No differences were seen in the overall percentage of children with IgE-mediated allergic disease in the first 3 years of life between the n-3 LCPUFA and control groups (64/368 (17.3%) vs 76/338 (22.6%); adjusted relative risk 0.78; 95% CI 0.58-1.06; P = 0.11). Eczema was the most common allergic disease; 13.8% of children in the n-3 LCPUFA group had eczema with sensitization compared with 19.0% in the control group (adjusted relative risk 0.75; 95% CI 0.53-1.05; P = 0.10). CONCLUSIONS: Overall, n-3 LCPUFA supplementation during pregnancy did not significantly reduce IgE-associated allergic disease in the first 3 years of life. Further studies should examine whether the nonsignificant reductions in IgE-associated allergies are of clinical and public health significance.

The influence of sun exposure in childhood and adolescence on atopic disease at adolescence.

BACKGROUND: It has been postulated that ultraviolet ray exposure in childhood might influence the development of allergic disease. We examined whether reported sun exposure during childhood or in adolescence is related to the occurrence of atopy or allergic disease. METHODS: Population-based longitudinal cohort study with sixteen-year follow-up (N = 415). Subjects were recruited at birth as part of an infant health study. The reported daily duration of sun exposure in the summer months was recorded at 8 and 16 yrs of age. Allergen sensitization and the presence of eczema, asthma, and rye grass positive rhinitis were recorded at age 16. RESULTS: Reported sun exposures of more than 4 h per day during summer holidays in adolescence were associated with reduced eczema and rhinitis but not inhalant allergen sensitization or asthma risk. Thus, higher sun exposure during summer holidays and summer weekends in adolescence was associated with significantly reduced eczema (test of trend p-value = 0.001 summer holidays; test of trend p-value = 0.003 summer weekends) and rye grass positive rhinitis (test of trend p-value = 0.03 summer holidays; test of trend p-value = 0.02 summer weekends). Sun exposure at adolescence or age 8 was not related to inhalant allergen sensitization. There was no association between serum 25(OH)D levels at adolescence with either inhalant allergen sensitization or allergic disease and adjustment for serum 25(OH)D levels did not alter these findings. CONCLUSIONS: Increased sun exposure during summer holidays in adolescence was associated with reduced eczema and rhinitis risk, independently of measured vitamin D levels but no difference in inhalant allergen sensitization or asthma. The beneficial effects of sun exposure on allergic disease may operate independently from vitamin D or an effect on allergen sensitization.

Persistent pollen exposure during infancy is associated with increased risk of subsequent childhood asthma and hayfever.

BACKGROUND: Few studies have focused on pollen exposure and asthma in children. None have examined associations between persistent exposure to pollen in infancy and aeroallergen sensitisation and asthma in childhood. OBJECTIVES: To examine the association between higher ambient levels of pollen in the first 3-6 months of life and risk of eczema, sensitization to food and aeroallergens at 2 years and asthma or hayfever at age 6-7 years combined. METHODS: Using a birth cohort of 620 infants with a family history of allergic disease born between 1990 and 1994, we examined risk of eczema or allergic sensitization (SPT > 3 mm to at least one of cow's milk, egg white, peanut, house dust-mite, rye grass, and cat dander) by age 2 and asthma or hayfever at age 6-7. Daily ambient levels of pollen were measured during this period. RESULTS: Cumulative exposure to pollen concentrations up to 6 months was associated with aeroallergen sensitization with the highest risk occurring at 3 months (aOR = 1.34, 95% CI 1.06-1.72). Cumulative exposure to pollen up to 3 months was also associated with hayfever (aOR = 1.14, 95% CI 1.009-1.29) and between 4 and 6 months exposure with asthma only (aOR=1.35, 95% CI 1.07-1.72). CONCLUSION: Persistent pollen exposure in infancy appears to increase the risk of asthma and hayfever in children. These results support the hypothesis that there is a critical window of opportunity in early development which may be important for modification of allergic outcomes.

Maternal probiotic supplementation during pregnancy and breast-feeding reduces the risk of eczema in the infant.

BACKGROUND: Probiotics have shown promising potential in reducing the risk of eczema in infants. Optimal probiotic intervention regimen remains to be determined. OBJECTIVE: We investigated whether maternal probiotic supplementation during pregnancy and breast-feeding reduces the risk of developing eczema in high-risk infants. METHODS: This was a parallel, double-blind placebo-controlled trial of 241 mother-infant pairs. Mothers with allergic disease and atopic sensitization were randomly assigned to receive (1) Lactobacillus rhamnosus LPR and Bifidobacterium longum BL999 (LPR+BL999), (2) L paracasei ST11 and B longum BL999 (ST11+BL999), or (3) placebo, beginning 2 months before delivery and during the first 2 months of breast-feeding. The infants were followed until the age of 24 months. Skin prick tests were performed at the ages of 6, 12, and 24 months. RESULTS: Altogether 205 infants completed the follow-up and were included in the analyses. The risk of developing eczema during the first 24 months of life was significantly reduced in infants of mothers receiving LPR+BL999 (odds ratio [OR], 0.17; 95% CI, 0.08-0.35; P < .001) and ST11+BL999 (OR, 0.16; 95% CI, 0.08-0.35; P < .001). The respective ORs for chronically persistent eczema were 0.30 (95% CI, 0.12-0.80; P = .016) and 0.17 (95% CI, 0.05-0.56; P = .003). Probiotics had no effect on the risk of atopic sensitization in the infants. No adverse effects were related to the use of probiotics. CONCLUSION: Prevention regimen with specific probiotics administered to the pregnant and breast-feeding mother, that is, prenatally and postnatally, is safe and effective in reducing the risk of eczema in infants with allergic mothers positive for skin prick test.

Impact of maternal allergy and use of probiotics during pregnancy on breast milk cytokines and food antibodies and development of allergy in children until 5 years.

BACKGROUND: Whether breast milk (BM) can protect against allergy has been studied extensively, with conflicting results. Variations in mothers' BM composition may explain some of the conflicting results. Our aim was to assess the impact of maternal allergy and probiotic intervention on BM food antibodies, transforming growth factor (TGF)-ß(2) and interleukin (IL)-10 and their impact on allergy development in children until the ages of 2 and 5. METHODS: We measured total IgA, IgA antibodies to cow's milk (CM), casein, ß-lactoglobulin and ovalbumin (OVA), TGF-ß(2) and IL-10 in 364 colostrum samples and 321 BM samples taken at 3 months from mothers participating in a prospective study evaluating the allergy-preventive effect of probiotics in a cohort with an increased risk for allergy. RESULTS: CM, casein and OVA antibodies, TGF-ß(2) and IL-10 were detectable in most samples. Maternal allergy was associated with raised levels of IgA to casein (p = 0.04) and lower levels of TGF-ß(2) (p = 0.006) in mature BM. Probiotic supplementation was associated with increased IL-10 (p = 0.046) and decreased casein IgA antibodies (p = 0.027) in mature BM. High OVA IgA antibodies in colostrum were associated with the development of atopy by the age of 2, while low levels in mature BM were a significant risk factor for the development of eczema by the age of 2. TGF-ß(2) levels in BM constituted a risk for development of allergy by the age of 2. CONCLUSIONS: The immunologic composition of BM was only slightly affected by maternal atopy and could be altered by probiotic supplementation. Small effects of BM components on allergy development in children were evident.

Can food allergy be prevented? The current evidence.

Food allergy is a recognized public health concern, for which preventative strategies are required. Although an intervention that adequately protects against the development of food allergy has still to be identified, limited benefits have been shown for the prevention of related allergic conditions such as eczema, and to a lesser extent asthma and rhinitis; these benefits are usually limited to at-risk populations. Prevention strategies need to be tested using randomized controlled study designs that account for the numerous methodological challenges, safety concerns, and necessary ethical limitations.

The most important contact sensitizers in Polish children and adolescents with atopy and chronic recurrent eczema as detected with the extended European Baseline Series.

The differential diagnostic work-up of children with chronic eczema should involve patch testing, also in cases with confirmed atopy. In our previous study, contact allergy was detected in every second child with chronic eczema. The aim of the present study was to identify the most important sensitizers in atopic children with eczema. During an allergy screening program, 103 consecutive children aged 7-8 and 93 adolescents aged 16-17 were enrolled. The inclusion criterion was chronic recurrent eczema as detected with the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire and atopy, defined as positive skin prick test to one or more common airborne or food allergens. The children were patch-tested with the newly extended European Baseline Series (EBS, 28 test substances) supplemented with propolis, thimerosal, benzalkonium chloride, and 2-phenoxyethanol. In total, 67.0% children and 58.1% adolescents were found patch test positive. Among children, 35.9% reacted to nickel, 16.5% propolis, 11.7% thimerosal, 9.7% cobalt, each 6.8% fragrance mix (FM) I and chromium, and 5.8% to FM II. Among adolescents, 37.6% reacted to thimerosal, 19.4% to nickel, 6.5% to cobalt, and 5.4% to propolis. We demonstrate the advantage of using FM II - a new addition to the EBS that detects a relatively high proportion of contact hypersensitivity among children. An important sensitizer from outside EBS is propolis, which according to the frequency of sensitization occupies rank 2 in children and rank 4 in adolescents. These data show that propolis should be included into routine patch testing in children.

Comparative in situ topoproteome analysis reveals differences in patch test-induced eczema: cytotoxicity-dominated nickel versus pleiotrope pollen reaction.

A subgroup of patients with atopic eczema develops acute eczematous reactions to type I allergy-inducing agents such as pollen that clinically resemble type IV allergies induced by haptens like metal ions. To clarify the underlying immunologic mechanisms, this study was designed to map the inflammatory in situ topoproteome of eczematous responses to grass/birch pollen and nickel by using atopy patch test (APT) and nickel patch test (NPT) as an appropriate clinical model, respectively. Biopsies from NPT (n = 6) and APT (n = 6) with positive reactions at 72 h were analysed by multiple epitope ligand cartography (MELC), which enabled to investigate coexpression of 49 different epitopes immunohistochemically in a single given tissue section. Colocalisation of IgE and FcepsilonRI was investigated by confocal microscopy. Compared with APT responses, NPT reactions were dominated by cytotoxic TIA-1 + and CD8 + T cells. In contrast, the immune response in APT reactions appeared more pleiotrope - as detected by colocalisation analysis. Multiple combinatorial molecular phenotype (CMP) motifs containing naive, early maturation and memory T cell (CD45RA, CD7, CD44, CD45R0), and general activation markers (CLA, HLA-DR, CD13, CD29, CD58, CD71, CD138) were significantly higher expressed in APT when compared with NPT reactions. APT response was confirmed to be accompanied by IgE bound to FcepsilonRI. In summary, our results demonstrate that the NPT reaction is clearly dominated by cytotoxic events, while the APT reaction to pollen grains is more heterogeneous and elicits a combined humoral and cellular immune reaction.