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.

Food beliefs and practices among the Kalenjin pregnant women in rural Uasin Gishu County, Kenya.

BACKGROUND: Understanding food beliefs and practices is critical to the development of dietary recommendations, nutritional programmes, and educational messages. This study aimed to understand the pregnancy food beliefs and practices and the underlying reasons for these among the contemporary rural Kalenjin communities of Uasin Gishu County, Kenya. METHODS: Through semi-structured interviews, data was collected from 154 pregnant and post-natal Kalenjin women about restricted and recommended foods, and why they are restricted or recommended during pregnancy. Respondents were purposively selected (based on diversity) from those attending Maternal and Child Health (MCH) care in 23 rural public health facilities. Key informant interviews (n = 9) with traditional Birth Attendants (TBA) who were also herbalists, community health workers, and nursing officers in charge of MCH were also conducted. Quantitative data was analysed using SPSS software. Data from respondents who gave consent to be tape recorded (n = 42) was transcribed and qualitatively analysed using MAXQDA software. RESULTS: The restriction of animal organs specifically the tongue, heart, udder and male reproductive organs, meat and eggs, and the recommendation of traditional green vegetables and milk was reported by more than 60% of the respondents. Recommendation of fruits, traditional herbs, ugali (a dish made of maize flour, millet flour, or Sorghum flour, sometimes mixed with cassava flour), porridge and liver, and restriction of avocadoes and oily food were reported by more than 20% of the respondents. The reasons for observing these dietary precautions were mainly fears of: big foetuses, less blood, lack of strength during birth, miscarriages or stillbirths, and maternal deaths as well as child's colic and poor skin conditions after birth. CONCLUSION: Pregnancy food beliefs were widely known and practised mainly to protect the health of the mother and child, and ensuring successful pregnancy outcome. Given the deep-rooted nature of the beliefs, it is advisable that when nutritious foods are restricted, nutritional interventions should rather search for alternative sources of nutrition which are available and considered to be appropriate for pregnancy. On the other hand, nutritional advice that does not address these health concerns and assumptions that underlie successful pregnancy and delivery is unlikely to be effective.

Fatty acid profile and sensory characteristics of table eggs from laying hens fed hempseed and hempseed oil.

UNLABELLED: Hempseed (HS) is rich in omega-3 polyunsaturated fatty acids, with approximately 17% of total fatty acids as alpha-linolenic acid. As such, HS and its oil may be used in hen diet formulations to produce eggs enriched in essential fatty acids. Because omega-3 eggs have the potential for unpleasant aromas and flavors, the current study was designed to assess the fatty acid profile and sensory attributes of eggs procured from hens consuming diets containing hempseed oil (HO) or HS. A total of 48 individually caged White Bovan hens received 1 of 6 diets containing 4%, 8%, 12% HO, 10%, 20% HS or 0% hemp (w/w) for 12 wk. Total omega-3 polyunsaturated fatty acid content was highest in the 12% HO group (15.3 mg/g of yolk) compared to the control (2.4 mg/g of yolk). Trained panellists (n= 8) found no significant differences (P≥ 0.05) in aroma or flavor between cooked eggs from different dietary treatments, with the exception of sweet flavor. The 4% HO group yielded the least sweet eggs compared to the 20% HS group, which was highest. For yolk color, L*, a*, and b* values (Mean ± SEM) for control eggs were 61.2 ± 0.10, 1.1 ± 0.05, and 43.0 ± 0.22, respectively. Addition of hemp led to significant (P < 0.001) reductions in L*, and significant increases in a* and b*, with the largest changes observed in the 20% HS treatment (L*= 58.7 ± 0.10; a*= 5.8 ± 0.05; b*= 60.5 ± 0.22). The results show that hemp use in hen diets leads to increased omega-3 polyunsaturated fatty acid content and color intensity of egg yolks, but does not have adverse effects on the sensory profiles of the cooked eggs. PRACTICAL APPLICATION: This study provides evidence that HS and hempseed oil (HO) can safely be utilized as feed ingredients for laying hens to produce table eggs that are enriched in essential fatty acids. Additionally, the eggs procured from these hens had similar aroma and flavor compared to eggs from hens not fed any hemp. The greater the dietary hemp inclusion, the more pigmented the resulting yolks became in terms of darkness, redness, and yellowness.

Effect of n-3 long chain polyunsaturated fatty acid supplementation in pregnancy on infants' allergies in first year of life: randomised controlled trial.

OBJECTIVE: To determine whether dietary n-3 long chain polyunsaturated fatty acid (LCPUFA) supplementation of pregnant women with a fetus at high risk of allergic disease reduces immunoglobulin E associated eczema or food allergy at 1 year of age. DESIGN: Follow-up of infants at high hereditary risk of allergic disease in the Docosahexaenoic Acid to Optimise Mother Infant Outcome (DOMInO) randomised controlled trial. SETTING: Adelaide, South Australia. PARTICIPANTS: 706 infants at high hereditary risk of developing allergic disease whose mothers were participating in the DOMInO trial. INTERVENTIONS: 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. MAIN OUTCOME MEASURE: Immunoglobulin E associated allergic disease (eczema or food allergy with sensitisation) at 1 year of age. RESULTS: No differences were seen in the overall percentage of infants with immunoglobulin E associated allergic disease between the n-3 LCPUFA and control groups (32/368 (9%) v 43/338 (13%); unadjusted relative risk 0.68, 95% confidence interval 0.43 to 1.05, P=0.08; adjusted relative risk 0.70, 0.45 to 1.09, P=0.12), although the percentage of infants diagnosed as having atopic eczema (that is, eczema with associated sensitisation) was lower in the n-3 LCPUFA group (26/368 (7%) v 39/338 (12%); unadjusted relative risk 0.61, 0.38 to 0.98, P=0.04; adjusted relative risk 0.64, 0.40 to 1.02, P=0.06). Fewer infants were sensitised to egg in the n-3 LCPUFA group (34/368 (9%) v 52/338 (15%); unadjusted relative risk 0.61, 0.40 to 0.91, P=0.02; adjusted relative risk 0.62, 0.41 to 0.93, P=0.02), but no difference between groups in immunoglobulin E associated food allergy was seen. CONCLUSION: n-3 LCPUFA supplementation in pregnancy did not reduce the overall incidence of immunoglobulin E associated allergies in the first year of life, although atopic eczema and egg sensitisation were lower. Longer term follow-up is needed to determine if supplementation has an effect on respiratory allergic diseases and aeroallergen sensitisation in childhood. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12610000735055 (DOMInO trial: ACTRN12605000569606).

Efeito da suplementação de linhaça, óleo de canola e vitamina E na dieta sobre as concentrações de ácidos graxos poliinsaturados em ovos de galinha / Effect of dietary supplementation of flaxseed, canola oil and vitamin E upon polyunsaturated fatty acids in chicken eggs

Estudou-se o efeito de diferentes fontes de ácidos graxos insaturados (óleo de canola e semente de linhaça), acrescidas de diferentes teores de alfa-tocoferol nas dietas de poedeiras, sobre a composição de ácidos graxos da gema do ovo foi estudado. Foram utilizadas 288 galinhas da linhagem Babcock que receberam dietas com 6 por cento de óleo de canola, 20 por cento de semente de linhaça moída ou 3 por cento de óleo de canola e 10 por cento de linhaça moída com teores de 0, 100 e 200UI/kg de alfa-tocoferol. As dietas com 20 por cento de semente de linhaça proporcionaram teores mais elevados de ácidos graxos poliinsaturados no ovo com aumento, em particular, dos teores de ácido alfa-linolênico e EPA (ácido eicosapentaenóico) e diminuição de ácido araquidônico na gema. Os teores de vitamina E contidos nas rações experimentais não determinaram alteração significativa na deposição dos diferentes ácidos graxos na gema dos ovos, exceto com relação aos ácidos graxos saturados.

The effect of dietary sources of polyunsaturated fatty acids - canola oil and flaxseed - with different vitamin E supplementation on the fatty acid deposition into the eggs of 288 Babcock laying hens was investigated. Birds were fed diets containing 6 percent of canola oil, 20 percent of flaxseed or a combination of 3 percent of canola oil and 10 percent of flaxseed, enriched with 0, 100 or 200Ul of dl-alpha-tocopheril acetate. The inclusion of flaxseed in the diets increased the yolk polyunsaturated fatty acids, mainly alpha-linolenic acid and EPA (eicosapentaenoic acid). The concentration of alpha-tocopherol in the diet did not change the egg yolk, fatty acids deposition but changed the saturated fatty acids deposition.

[Clinical importance of cross-reactivity between allergens]. / Implicación clínica de la reactividad cruzada entre alergenos.

Cross reactivity describes the development of symptoms as a consequence of the presence of specific IgE to a protein without the subject having had previous contact with that protein. Cross-reactivity depends on factors such as the individual's immune response, the type and intensity of exposure and, above all, the type of allergen. The identification of pan-allergens, which are present in various animal and vegetable sources and which show great structural and sequential similarity, even among species with little taxonomic relation, explains the existence of distinct, well-defined cross-reactivity syndromes. Knowledge of these phenomena could have important diagnostic and therapeutic consequences.

Implicación clínica de la reactividad cruzada entre alergenos / Clinical importance of cross-reactivity between allergens

La Reactividad Cruzada (RC) expresa el desarrollo de síntomas como consecuencia de la presencia de IgE específica frente a una fuente proteica sin que haya existido contacto previo con la misma. La RC depende de factores como la respuesta inmune del individuo, del tipo e intensidad de la exposición y, sobre todo, de la naturaleza del alergeno. En este sentido, la identificación de Pan-alergenos, presentes en diferentes fuentes de origen animal y vegetal, compartiendo una gran similitud estructural y secuencial, incluso entre especies taxonómicamente muy poco relacionadas, explica la existencia de diferentes síndromes de RC bien definidos. El conocimiento de estos hechos puede tener importantes consecuencias de tipo diagnóstico y terapéutico (AU)

Cross reactivity describes the development of symptoms as a consequence of the presence of specific IgE to a protein without the subject having had previous contact with that protein. Cross-reactivity depends on factors such as the individual's immune response, the type and intensity of exposure and, above all, the type of allergen. The identification of pan-allergens, which are present in various animal and vegetable sources and which show great structural and sequential similarity, even among species with little taxonomic relation, explains the existence of distinct, well-defined cross-reactivity syndromes. Knowledge of these phenomena could have important diagnostic and therapeutic consequences (AU)

Sensitization to food and airborne allergens in children with atopic dermatitis followed up to 7 years of age.

Previously we investigated the eczema prognosis and the risk of developing allergic asthma and rhinitis in a cohort of 94 children with atopic dermatitis. In this second study on the same cohort we address the development of sensitization to foods and airborne allergens, risk factors and, the question whether children with atopic dermatitis who will not become sensitized can be recognized early. Children with atopic dermatitis were followed up regularly from infancy or early childhood to 7 years of age with clinical examination and blood sampling. After age 3, skin prick tests with inhalation allergens were performed yearly. In most children both clinical allergy and sensitization to egg and milk were transient but those to peanut were persistent. Eighty per cent of the children became sensitized to airborne allergens and 75% of them noticed symptoms when exposed. Heredity for atopy and eczema, sensitization to hen's egg, and early onset of eczema entailed an increased risk of becoming sensitized. Children never sensitized had late onset of eczema and less heredity for atopic disease but did not differ in other respects from the sensitized children.

What safety measures need to be taken in oral food challenges in children?

BACKGROUND: Food allergens are often accused of causing numerous ailments. This is particularly true for the pediatric population, where the incidence of food allergy is four times as high as in adults. As food challenges may provoke life-threatening reactions, intensive safety measures need to be taken during provocation, and prompt medical intervention may become necessary. METHODS: We retrospectively evaluated 349 oral challenges in 204 children with atopic dermatitis, looking for criteria to help the physician decide which patients need medical intervention. RESULTS: A total of 178 (51%) oral food challenges with the four allergens (cow's milk [CM], hen's egg [HE], wheat, and soy) showed a positive clinical reaction. Of these, 120 (67%) needed medical intervention. In 42 (35%) cases, intervention was parenteral, and oral medication was given in 78 (65%) cases. There was a strong positive correlation (90%) between the level of specific IgE and the need for medical intervention (> or = 17.50 kU/l for CM, wheat, and soy; > or = 3.50 kU/l for HE). Patient history of food allergy was an indicator of the need for medical intervention (P = 0.01). A positive patient history and a high level of specific IgE were significantly (P=0.003) associated with parenteral medication in HE. CONCLUSIONS: Patient history of food allergy is a reliable indicator of the need for medical intervention in the cases of CM, wheat, and soy regardless of the level of specific IgE. With HE, a positive patient history plus a high level of specific IgE significantly indicates the need for parenteral medication. On the basis of our results, we recommend establishing intravenous access in children with a level of specific IgE of > or = 17.50 kU/l (CAP class 4) to CM and wheat, or with specific IgE of > or =3.50 kU/l (CAP class 3) to HE.

[Immuno-biological diagnosis of food allergy]. / Diagnostic immuno-biologique de l'allergie alimentaire.

Food allergy is becoming more frequent, with 6% of asthmatics reporting an isolated food allergy, and 5 to 6% of atopic dermatitis patients also have either a single or multiple true food allergy. There is value in immuno-biological diagnosis by: Measurement of total serum IgE. Measurement of mono-allergen-specific IgE, following a measurement by a multi-allergen of the Trophatope type. A study of elimination of foods for 2 or 3 months followed by their re-introduction. Oral provocation tests in a hospital environment under clinical control and subsequent measurement of the mediators:-Plasma histamine, tryptase, and urinary methylhistamine to give proof of responsibility of the food allergen. Nowadays, it is perfectly possible to include in diagnosis the new technologies of the test of activation of basophils/or lymphocytes by means of flow cytometry.

Skin manifestations and immunological parameters in childhood food allergy.

According to Hansen's contact rule, the digestive system should be considered as the main shock organ, yet in food allergy, this is not the case. Very often specific food triggers clinical manifestations not involving the digestive system; that is, reactions are manifested either in the respiratory system, as asthma or rhinitis, or in the skin. In these cases the BALT (broncho-alveolar lymphoid tissue) and GALT (gastrointestinal lymphoid tissue) units play a basic role in the sensitizations. The purpose of this study was to determine the most frequent skin manifestations of food allergy among children, and the most frequently involved foods. We also thought it interesting to evaluate the diagnostic reliability of the different standard immunological parameters utilized by the study team in food allergy. All patients underwent intracutaneous tests with 12 groups of the most frequent food allergens, as well as serum IgE, antigen-specific IgE against foods, and antigen-specific histamine release tests. Antigen-specific IgG4 determination was performed in some cases. The results obtained confirmed previous studies, the most common manifestations being: angioedema (48%), followed by urticaria (31%) and atopic dermatitis (21%). Regarding the frequency of sensitization to different food allergens, in mono- or polisensitization, fish and egg stand out in our environment. Certain food allergens are more frequently responsible for specific skin manifestations. Thus, for fish sensitization, the most frequent skin manifestation is atopic dermatitis (50%); for egg sensitization, angioedema is the most frequent skin manifestation (50%); and for milk, urticaria (50%). Finally, and in agreement with previous works regarding the diagnostic reliability of in vitro techniques, we found that the histamine release test offered the highest percentage of diagnostic reliability. Only for sensitization to milk proteins did antigen-specific IgE demonstrate higher reliability. Once again, we stress that our main problem is the lower reliability of skin tests against food allergens than against inhalant allergens. We emphasize the importance of food as a major factor in the etiopathogenesis of atopic dermatitis, as well as the need to complement the study, when possible, by means of the in vitro techniques described.

Thyroid function and other clinical chemistry parameters in subjects eating iodine-enriched eggs.

Iodine-enriched (IE) eggs are produced by chickens fed a diet containing kelp. These eggs, which contain an average of 711 micrograms iodine/egg, have been reported to reduce plasma cholesterol in humans and laboratory animals. A modified form of these eggs is under consideration for marketing in the United States. 104 hyperlipidaemic subjects were placed on a low-fat diet for 12 wk. Between wk 4 and 12, approximately half of the subjects were randomized to a dietary control group (n = 53) or a group who ingested one IE egg/day in addition to this diet (n = 51). Some subjects in both groups continued in the study for an additional 4-8 wk. No significant adverse clinical effects were observed or reported, with the exception of one subject who reported an allergic-like reaction soon after beginning egg ingestion. All clinical chemistry values remained within normal limits, and comparisons between the egg group and controls were not significant. Three subjects (two in the egg group and one in the control group) had elevated thyroid stimulating hormone levels during the experimental period. All thyroid function tests remained within normal limits in the remaining subjects. Thus, ingestion of one IE egg of the type used in our study appears to be relatively safe and devoid of clinically significant, short-term adverse effects in healthy individuals.

Risk factors for stomach cancer in sixty-five Chinese counties.

Stomach cancer mortality data were compared with dietary and biochemical data from 65 Chinese counties to provide clues to reasons for the marked geographic variation of stomach cancer mortality rates in China. Sex-specific correlation and multivariate regression analyses showed significant positive associations with consumption of salted vegetables and eggs, prevalence of antibodies to Helicobacter pylori, and levels of plasma albumin; and significant negative associations with intake of green vegetables and levels of plasma selenium and beta-carotene. Limitations of ecological data preclude causal inferences, but these findings suggest factors that may contribute to making stomach cancer the leading cause of cancer death in China and other countries.

Effects of maternal diet during late pregnancy and lactation on the development of atopic diseases in infants up to 18 months of age--in-vivo results.

One hundred and sixty-two women with respiratory allergy to animal danders and/or pollens were randomly allocated to a diet consisting of either a very low ingestion of hens' egg and cows' milk or a daily ingestion of one hens' egg and about 11 of cows' milk during the last 3 months of pregnancy. One hundred and sixty-three infants were followed prospectively up to 18 months of age when the cumulated incidence of atopic disease in each child was evaluated blindly. No significant differences in the distribution of atopic disease were found among the infants in relation to the maternal diet during late pregnancy. The numbers of skin-prick tests positive to ovalbumin, ovomucoid, beta-lactoglobulin and cows' milk were likewise not influenced by differences in the maternal diet during late pregnancy. Genetic factors rather than maternal diet during the perinatal period probably have a greater effect on the incidence of atopic diseases during early infancy.

[Idiopathic nephrotic syndrome and food hypersensitivity. Value of an exclusion diet]. / Syndrome néphrotique idiopathique et hypersensibilité alimentaire. Valeur des régimes d'éviction.

A case of idiopathic nephrotic syndrome (INS) evolving since more than 7 years with 4 successive corticosensitive relapses is reported. At the time of a 5th relapse corticosteroid treatment was refused by the parents and evolution went on without any spontaneous tendency to remission. Three months later, allergy tests detected various sensitizations, especially for food allergens. An antiallergic treatment including dietary exclusions induced a complete and durable remission. Five similar cases are reported. These facts, compared to data from the literature, indicate the possible role of food hypersensitivity in INS. Its mechanism has been discussed; the possible part of a lymphocyte activation has been emphasized.

Maternal abstention from cow milk and egg in allergy risk pregnancies. Effect on antibody production in the mother and the newborn.

To study the possibility of intrauterine sensitization, 212 women were enrolled on a voluntary basis into a prospective, randomized study, comparing the effects of an elimination diet and normal food during late pregnancy. The diet group took no cow milk and no egg from week 28 to delivery, and extra calcium and casein hydrolysate (Nutramigen) supplement was given to fill the nutritional needs of mother and child. The control group took normal food, including approximately 1/2 liter of milk/day and 3-5 eggs/week. All families had a history of allergy in mother, father, or sibling. Maternal weight gain during pregnancy was significantly lower in the diet group. Birth weights showed no significant difference between the two main groups, but smokers in the elimination diet group had significantly smaller babies. IgE antibodies to cow milk and egg were significantly higher in atopic than in non-atopic women before the trial. The diet caused a significant fall in IgG-antibodies to cow milk and egg in both atopic and non-atopic subjects. Cord blood IgE determination revealed no significant difference between the groups. No IgE antibodies to cow milk or egg were detected in any of the cord sera. The participating babies are being followed up until 18 months of age.

IgE antibodies to foods are not a feature of cystic fibrosis.

It has been suggested that patients with cystic fibrosis have abnormal immune responses to foods. We have measured IgE antibodies to inhalants and foods (by RAST) in 105 patients with cystic fibrosis aged between 8 months and 28 years. Serum IgE was elevated (greater than 180 kU/l) in 21 patients. In 43, IgE antibodies were detected in serum. The majority of positive results were with house-dust mite, grass pollen or Aspergillus. Only four of the patients had a positive RAST to a food--one to milk, one to wheat and two to egg. On the basis of high serum IgE or positive RAST results, 44.8 per cent of the patients were atopic and the frequency of atopy was age-related, being higher in patients aged 4 years or more. However, the presence of food antibodies was unrelated to age. This study confirms the high prevalence of atopy in patients with cystic fibrosis but unequivocally demonstrates that the presence of IgE antibodies to foods in their serum is rare.